ANNUAL REPORT OF THE AFLATOXIN RESEARCH PROJECT ON GROUNDNUTS IN MALAWI FOR THE PERIOD FROM AUGUST 1, 1997 - JANUARY 1999 (RY 2000)

Report by Charles Kisymobe and Summary by David Wilson and Charles Kisyombe

SUMMARY: The project on groundnut in Malawi was initiated in the 1997-1998 growing season. The market survey was initiated in Malawi in

1997-1998, the first year 29 groundnut samples were collected from vendors and farmers. No highly contaminated samples were found in the

market, the aflatoxin content ranged from non detectable to 4 ppb total aflatoxins. Peanut genotypes commonly grown and promising ICRISAT

genotypes were grown at three locations in Malawi in a randomized complete block design. Many yeild and quailty factors wer measured as well

as aflatoxin and Aspergillus flavus. The pea nuts were separated into those with no damage, mechanically damaged, termite scarified, immature

and rotted before analysis for aflatoxins and mycoflora. No high amounts of aflatoxins were found in any of the good peanuts in 1997-98. In future

years the damaged peanuts will be recombined and aflatoxin measurements made on these high risk components. There was a significant

difference in Aspergillus flavus incidence in peanut genotypes in some of the locations in Malawi. This study was repeated in 1998-1999 and it will

be interesting to see if this relationship holds up.

. INTRODUCTION:

Malawi is a long, narrow and land-locked country in the Central East Africa lying between 9o45 and 17

o6south of the Equator and between 33

o and 36

o east

of the Greenwich meridian. It is 900 kilometres in length from north to south and varying in width from 80 to 160 kilometres. It has a total area of 118, 484

km2 of which 94,276 km2 is land and 24,94,276 km2 is covered by water. Malawi is bordered to the north and north-east by Tanzania, to the west by

Zambia and to the south-west, south, south-east and east by Mozambique. The country is heavily dissected and has gently undulating land forms with

altitudes varying from 200 metres above sea-level to approximately 1,500 metres above sea-level. The country is characterized by mountainous and hilly

zones where steep slopes represent ecologically fragile areas. The varied topography has a major influence on the climate, drainage, soils, vegetation and

agriculture.

The climatic conditions throughout the year form two district seasons:

1. The rainy season from November to April.

2. The dry season from May to October. Rainfall is fairly reliable and unevenly distributed during the season with a range of 700 to 1,600 mm.

There are three main agroclimatic zones:

1. The plateaux 2. The Lakeshore, and 3. The Shire Valley.

These agroclimatic zones have different climatic conditions due to differences in altitude. The large variation in climatic conditions provide Malawi with a

high potential for the production of a wide range of crops. This also presents the country with more complications and challenges for agricultural research

in developing appropriate technologies.

Malawi's population is currently estimated at about 10 million with an average growth rate of 3.3% per year and with an avera ge population density of

almost 106 persons. Km-2, making the country one of the most densely populated countries in sub-Saharan Africa. An estimated 50% of the population is

under the age of 15 years and more than 90% of the total population lives in rural areas.

Crops and livestock (agriculture) contribute about 33% of the Gross Domestic Project (GDP) and account for 90% of the foreign exchange. The main cash

crops are: tobacco, sugar from sugarcane, tea and coffee. These account for more than 80% of the total exports. Maize is the most important staple food

crop to the Malawian population and it occupies 68% of the land under crops.

Over 70% of the cultivated area in Malawi is under the customary land tenure system and is utilized by 2.86 million smallholder families with holdings

ranging from 0.1 to 2.5 hectares. Smallholder farmers produce numerous crops where the common practices are mixed cropping and land race or cultivar

diversity strategies that avoid risk rather than maximize productivity in Malawi. These crops are: tobacco, maize, groundnuts, pulses, sweet potatoes,

cassava, sorghum, rice, Irish potatoes, sunflower, coffee, macadamia, cashew and spices. Malawian smallholder farmers also raise livestock such as cattle,

sheep, poultry, goats, rabbits pigs, ducks, guinea fowl and guinea pigs.

The estate sector utilizes approximately 5% of the cultivated area on more than 1,300 units under the leasehold and free - hold tenure system. This sector

primarily produces burley and flue-cured tobacco, sugar from sugarcane, coffee, tea and treenuts. Together, crops and livestock agriculture on the estates

contribute about 80% of the total agricultural production in Malawi.

Any future increases in agricultural production in Malawi will have to come from improving crop and livestock yields per unit area instead of increasing

land under cultivation. This urgently requires modern technology developed through research to promote increased yields and improved nutrition for

farmers and their families.

The overall Malawi Government policy is to improve the well-being of the people through poverty alleviation especially among the most populous rural

inhabitants by promoting broad-based and rapid agricultural development.

As part of the overall aim of rural poverty alleviation other objectives of Malawi's agriculture and livestock development include:

1. Improving food self-sufficiency and the nutritional status of the population.

2. Encouraging self-reliance through increased broad-based small scale agro-industries and businesses

3. Expanding and diversifying crop's and livestock products' exports.

4. Raising farm incomes and promoting economic growth while conserving natural resources.

It is envisaged that these policy objectives will be achieved by minimizing:

1. The deterioration of natural resources.

2. The serious disproportionate distribution of crop and

livestock incomes,

3. The over-dependency on volatile external trade flows.

THE ROLE OF GROUNDNUTS IN THE ECONOMY OF MALAWI

Groundnut (Arachis hypogaea L.) is a very important crop in Malawi. It is widely grown and used both for food and for sale to generate cash income.

Groundnut provides approximately 25% of the agricultural cash income in rural areas in Malawi. In addition, groundnut also provides supplementary cash

income to women farmers who support their families, especially health and education of children. The groundnut seed contain approximately 25%

digestible protein and 50% edible oil. The seed also contain certain essential amino acids like: cystine, and vitamins like: thiamin, riboflavin and niacin.

The groundnut is therefore an important component of the diet in both rural and urban areas in Malawi.

Groundnut is consumed in various ways in Malawi. It is prepared as roasted pods/seed, boiled fresh nuts, seed crushed into peanut butter or added to

traditional vegetable dishes as a sauce and edible oil. Therefore, the groundnut plays an important role in the family health and nutrition particularly for

women and children health and development in Malawi.

Groundnut haulms (either fresh or dried) and seed cake are valuable livestock feed in Malawi.

Groundnut being a legume crop, improves soil fertility and provides beneficial residual effects for the productivity of subsequent cereal crops like maize,

sorghum and millets.

Groundnut pod yields in Malawi are generally low averaging 700 kg.ha-1 in marked contrast to yields of over 4,000kg.ha-1 obtained at research stations.

The decline in groundnut production and productivity is due to several factors ranging from biotic to abiotic stresses and marketing problems.

Groundnut production constraints are many and varied but some affect most areas of the country. These constraints include non-availability of seed of

improved cultivars adapted to various agroecological zones, poor soil fertility and cultural practices, diseases (rosette, early leaf spot and aflatoxin

contamination) and arthropod pests such as termites.

Groundnut is a rain - fed crop in most areas of Malawi. It is cultivated either as a sole crop or in association with such cereals as maize and sorghum or

millet or legumes such as pigeonpeas. The bulk of the crop is grown mainly in the plateaux especially in the Lilongwe-Kasungu Plain in Central Malawi

where over 70% of the crop is produced. Other important areas are the Mzimba Plain, the Lakeshore Plains and the Shire Valley. Off -season groundnut is

produced in some parts of Nkhata Bay and Karonga Rural Development Projects.

HARVESTING AND DRYING OF GROUNDNUTS IN MALAWI

In Malawi farmers begin to harvest groundnuts from mid-April onwards. During this time the temperature and relative humidity decrease. Where over 70%

of the groundnut crop is produced in the Lilongwe, Dowa, Kasungu and Mzimba districts temperatures are low during the months of May to August.

During the winter months a characteristically gentle wind blows and relative humidities in this air -stream are 50-60%. Most of the groundnut crop is

produced by long season cultivars which mature as the rains come to an end and harvesting conditions are good: the soil is still workable, which permits

easy lifting and the reductions in temperature and humidity allow rapid and efficient drying.

Harvesting and drying of groundnuts coincide with harvesting of other crops which in Malawi are more important than groundnuts. These crops are maize

which is the staple food for most of the people in Malawi and tobacco which is the most important high cash value crop in Malawi. This scenario leads

farmers to harvest groundnuts and then leave them in the field to sun-air dry until when these valuable crops have been harvested and safely stored.

Consequently, groundnuts becomeover dry in the field and they lose considerable weight. Thus the groundnut kernels will be at a very low moisture

content of about 5.0%. In Malawi farmers would lose money if they were to sell over - dried groundnutsbecause the produce is bought by traders and others

by measuring by weight.

Therefore, when some farmers prepare groundnuts for sale, they unfortunately remoisten the dry pods because of two main reasons:

1. To make the shell softer so that the pods are easier to crack by hand. Smallholder farmers in Malawi cannot afford to purchase and use groundnut

shelling machines.

2. To make up for the considerable loss in weight of the kernels due to the over - drying in the sun in the windrow in the field.

The two above mentioned farmers' practices are contrary to the recommended agricultural extension advice on the proper processing of groundnuts prior to

selling the commodity to buyers in Malawi.

MARKETING AND PROCESSING OF GROUNDNUTS IN MALAWI

Prior to 1989, the Agricultural Development and Marketing Corporation (ADMARC), a parastatal of the Government of Malawi was the sole purchaser of

groundnuts from farmers at over 500 buying stations throughout the country. The whole of the export crop was used exclusively for confectionery purposes

on the world market and therefore the quality of the crop was all - important. ADMARC used to buy only the following three grades of groundnuts at their

markets and no mouldy diseased kernels were purchased:

1. Chalimbana type - large, whole, clean kernels

2. Mwitunde/kalisele type - smaller, whole, clean kernels.

3. Split or shriveled kernels.

Both whole clean kernel grades were then transported to the Liwonde Groundnut Factory in Southern Malawi where they were subjected to further grading

and sorting and a representative sample of groundnuts from each lot taken for aflatoxin analysis. The groundnut consignment was exported only when it

had a very low level of aflatoxins (below 5 ng.g-1). The graded seed were then fumigated and sprayed with an insecticide before being exported.

The entire confectionery crop was hand shelled and farmers rejected any immature, diseased or broken kernels before offering them for sale. Wrinkled or

split kernels were not exported. Because of these stringent standards set and upheld by ADMARC, Malawi had gained a good reputation on the world

market as an exporter of high quality groundnuts.

The wrinkled or split kernels which were referred to as grade x nuts were crushed for oil and the resulting cake was used as livestock feed.

The trading of groundnuts in Malawi is currently liberalized and anyone can engage in the purchase and sale including the export of this commodity as long

as a trading licence has been obtained from the Government of Malawi.

ADMARC continues to purchase and process groundnuts the way it used to do before the trade was liberalized in 1989 however the volume of groundnuts

it is currently handling is drastically reduced because of competition from the intermediate or private traders. These intermediate traders buy and sell the

groundnuts including export of the commodity. Although the intermediate traders buy and sell and export groundnuts, they do not test groundnuts for

aflatoxin contamination. Testing facilities and procedures are already in place in the country. The traders can use these services at a small fee.

The groundnut products such as refined cooking oil and groundnut butter sold by the large commercial companies like Lever Brothers, Kukoma, National

Seed Company and others in Malawi are probably free from aflatoxin contamination. This is because these products are produced under very stringent

conditions to minimize aflatoxin contamination in the cooking oil. However, the by-product groundnut cake could contain unacceptably high levels of

aflatoxin especially when it is stored for extended periods of time prior to utilizing it as livestock feed. Testing of these by-products needs to be done prior

to feeding them to livestock.

Nevertheless, the crude cooking oil, groundnut cake and groundnut butter produced under conditions in cottage industries established in Malawi with

funding from Non-Governmental Organizations (NGOs) could contain unacceptably high levels of aflatoxins which may be detrimental to the health of the

smallholder farmers and especially their children including babies.

In Malawi no one knows the effects of ingesting aflatoxin contaminated groundnuts and processed groundnuts. Mouldy groundnuts and processed

groundnuts which have been infected with Aspergillus flavus Link ex fries and Aspergillus parasiticus Speare and possibly contaminated with aflatoxins

are frequently encountered in the country. People discard the apparently mouldy or rotten groundnuts and processed groundnuts but they will consume any

groundnuts and processed groundnuts that apear clean and sound.

In Malawi no comprehensive studies have been done to determine the extent of the aflatoxin contamination problem in groundnuts and processed

groundnuts. The data from a few attempted surveys provide inconclusive information on the problem in the country. These dearth data provide

inconclusive information because of funding limitations to conduct comprehensive surveys on the aflatoxin contamination problem in groundnuts and

processed groundnuts. Consequently, two schools of thought prevail in Malawi on the aflatoxin problem. One school of thought is that the aflatoxin

contamination problem in groundnuts and processed groundnuts is very serious in the country and researchers are deliberately neglecting this health hazard.

The second school of thought is that the problem is not serious at all. This has resulted from the commendable efforts of the Agricultural Extension

Workers in educating farmers on the proper harvesting and drying and storage of groundnuts. Therefore, some people in Malawi consider the aflatoxin

contamination problem in groundnuts and processed groundnuts not to be as serious as previously envisaged. These controversie s and speculations can only be resolved by conducting comprehensive studies on the aflatoxin contamination problem of groundnuts and processed groundnuts. These studies

should be in the form of surveys encompassing a wide spectrum of people who derive their livelihood from cultivating, handling, processing, transporting,

storing and trading in groundnuts and processed groundnuts in Malawi.

Nevertheless, the aflatoxin contamination problem in groundnuts and processed groundnuts could be serious because both the bi otic and abiotic stresses

that exacerbate the problem in the pre-harvest and postharvest groundnuts and processed groundnuts are prevalent in Malawi.

The biotic stresses in pre-harvest groundnuts include the following:

1. Susceptible commercial varieties.

2. Soil inhabiting arthropod pests such as termites and others.

3. Pod-rotting fungi such as Fusarium solani, F.oxysporum, Macrophomina

phaseolina and many others.

4. Plant stress caused by high or low plant densities, diseases and weeds.

5. Prevalence of aflatoxigenic strains of Aspergillus flavus group of fungi

6. Bird damage

7. Rodent damage

The abiotic (environmental) stresses in pre-harvest groundnuts include the following:

1. Drought and lack of adequate irrigation facilities

2. High soil temperatures

3. Non-availability or inadequate availability of fertilizers such as calcium.

4. Nutrient imbalances such as too little or too much of one type of a nutrient

especially the micronutrients.

5. Poor tillage practices such as lack of subsoiling to break up the plant root impenetrable zone.

6. Inappropriate sowing dates whereby the physiological maturity stage of

the groundnuts coincides with terminal drought, high soil temperatures

and/or high arthropod pest and diseases attack.

7. Mechanical damage to the plants during weeding and harvesting of the

groundnuts.

The biotic stresses in the postharvest groundnuts and processed groundnuts include the following:

1. Susceptible commercial varieties

2. Arthropod pests such as termites and Nezara; and storage pests such as

Ephestia cautella (Wlk.) and Tribolium spp.

3. Pod-rotting fungi especially where there are unsatisfactory storage facilities where the roofing material leaves a lot to be desired (microbial

deterioration).

4. Prevalence of aflatoxigenic strains of Aspergillus flavus group of fungi

5. Bird damage

6. Rodent damage

7. Lack of knowledge on or the irresponsible handling and processing of groundnuts and processed groundnuts by the human workers.

The abiotic (environmental) stresses in the postharvest groundnuts and processed groundnuts include the following:

1. Mechanical damage

2. High storage temperatures

3. Insufficient drying conditions and facilities

4. High moisture content in the seed in storage.

5. Unsatisfactory storage infrastructure with a roof that leaks

6. Poor processing conditions

7. Poor conditions during transportation

8. Non-availability of sufficient aflatoxin testing facilities for groundnuts to be

exported by the intermediate traders.

9. Liberalization of the groundnut trade in Malawi because it difficult to monitor the produce for aflatoxin contamination.

Comprehensive research into the aflatoxin contamination problem in groundnuts and processed groundnuts would inevitably shed light into the extent of

this problem in Malawi. It is hoped that the findings of this project will have local, regional and global implications especially in those countries where the

Malawi groundnuts and processed groundnuts are exported to and consumed.

The main objectives of the aflatoxin research project on groundnuts in Malawi are as follows:

1. To conduct a comprehensive survey of the infections of the Aspergillus flavus group of fungi and the aflatoxin contamination problem in groundnuts and

processed groundnuts in Malawi

2. To screen groundnut genotypes for stability of resistance to infection by Aspergillus flavus under field conditions in Malawi.

3. To conduct course training sessions for Technical Assistants (T.A.s), Field Assistants (F.A.s); Traders and Processors in order to create awareness on the

risks and avoidance of the aflatoxin contamination problem in groundnuts and processed groundnuts in Malawi.

A. REPORT OF THE SURVEY OF THE INFECTIONS OF Aspergillus flavus GROUP OF FUNGI AND THE AFLATOXIN

CONTAMINATION PROBLEM IN GROUNDNUTS AND PROCESSED GROUNDNUTS

IN MALAWI FROM AUGUST 1997 TO JANUARY 1999

The activities of the survey of the infections of Aspergillus flavus group of fungi and the aflatoxin contamination problem in groundnuts and processed

groundnuts in Malawi involved the following:

1. Development of a survey questionnaire and purchase of groundnuts and processed groundnuts samples from farmers, traders, processors and others. 2. Isolation of the A. flavus group of fungi and other resident seed microorganism by conducting mycological tests. 3. Quantification of the aflatoxin contamination in the seed and processed groundnuts by conduting aflatoxin analyses.

A survey questionnaire for interviewing the smallholder farmers and traders was developed.

The survey commenced after receiving the first advance of US$10,000.00 (Ten thousand US Dollars) for the Aflatoxin Research Project on Groundnuts in

Malawi. The cheque was received August 7, 1997.

Smallholder farmers and traders were interviewed while completing the questionnaire. Samples of 5.0 kilograms of unshelled groundnuts and 2.0

kilograms of groundnut meal were purchased from each farmer or trader at a price mutually agreed upon. Processed groundnuts were purchased at a price

set by the traders either at local markets or supermarkets in the cities. All the samples were packed in clean plastic bags and taken to the Groundnut

Pathology Laboratory at Chitedze Agricultural Research Station in Lilongwe for mycological tests and aflatoxin analysis.

MYCOLOGICAL TESTS

At Chitedze the groundnut pods were carefully cracked by hand and 100 seed were selected. The seed were surface sterilized by completely immersing in

1% sodium hypochlorite (1% v/v available chlorine) and swirling the seed in the beaker for 1 minute. The seed were washed three times in sterile distilled

water for 1 minute each time. The seed were blotted dry with a sterile filter paper or tissue paper. Five seed were asceptically plated into each 9-cm Petri

dish containing Malt Extract Agar (MEA) ammended with 6% sodium chloride. This was done in an inoculation hood using a flame sterilized pair of

folceps. Twenty Petri dishes were used to plate out the 100 seed from each sample. The Petri dishes were incubated at an ambient temperature of about 20o

- 30oC on the laboratory bench for 10-14 days. Records were taken by counting the seed internally infected by the Aspergillus flavus group of fungi. The

percent infection/isolation was calculated for each sample. Other resident microorganisms isolated from the seed were identified using a hand lens and

recorded for each sample. The hand lens was also used to confirm the identify of the A. flavus group of fungi.

AFLATOXIN ANALYSIS

After the 100 seed were selected for mycological tests the remaining seed were subjected to an aflatoxin analysis. All the visibly discoloured and rotten

seed were discarded because these are the seed farmers do not eat. Then the seed were ground in a mill and the moisture content in the resulting groundnut

flour for each sample was determined using the drying oven technique in the aflatoxin analysis laboratory.

The aflatoxin analysis was determined by the CONTAMINATION BRANCH (CB) protocol. The total aflatoxin B1 content was determined for each

sample bought from a farmer or trader.

RESULTS AND DISCUSSION

A questionnaire was developed for interviewing both farmers and traders (See the attached questionnaire in Appendix I). Although the questionnaire was

not pre-tested to ascertain the quality of data that would be collected in the survey, data were obtained from famers and traders especially when the

Agricultural Extension Staff accompanied us to go and conduct the interviews. This was chiefly because it was easier to communicate with the farmers and

traders when the Agricultural Extension Staff were involved.

The details of the farmers and traders interviewed and the samples purchased are presented in Table 1. The groundnut and processed groundnut samples

were purchased from the following Rural Development Projects:

1. Ntcheui 2. Thiwi - Lifidzi 3. Dedza Hills 4. Lilongwe East, and 5. Lilongwe West.

It should be noted that the areas which were visited during the survey covered some of the areas where more than 70% of the groundnut crop is produced in

Malawi.

A total of 29 samples (groundnuts and processed groundnut samples) were bought from farmers and traders during the survey and they were from the

following areas:

1. Ntcheu Rural Development Project = 8 samples

2. Thiwi-Lifidzi Rural Development Project = 5 samples

3. Dedza Hills Rural Development Project = 2 samples

4. Lilongwe East Rural Development Project = 8 samples

5. Lilongwe West Rural Development Project = 6 samples

TOTAL = 29 SAMPLES

The samples comprised of the following types of groundnuts and processed groundnuts:

1. Kalisele groundnuts

2. Mixture of groundnut varieties

3. Groundnut meal

4. Chalimbana groundnuts

6. Groundnut (Peanut)butter.

ISOLATIONS OF THE ASPERGILLUS FLAVUS GROUP OF FUNGI

The percent infections of the groundnut seed by the A. flavus group of fungi are presented in Table 2.

The infections of the groundnut seed by the A. flavus group of fungi ranged from 39 - 89%. Sample No. 23 from Lilongwe West which comprised of

mixture of groundnut varieties had the least level of infections of A.flavus group of fungi of 39%. However, the sample also had infections of other resident

seed microorganisms such as Fusariumspp., Aspergillus niger, Penicillium spp., Trichoderma sp. and

Rhizopus sp.

These resident seed microorganisms which were isolated also produce mycotoxins which are known to be hazardous to humans and animals.

Microorganisms such as Fusarium spp., Penicillium spp. and other types of aspergilli produce the following mycotoxins: ochratoxin A, sterigmatocystin,

patulin, penicillic acid, deoxynivalenol, zearalenone and fumonisin. However, certain fungi which were associated with the afore-mentioned

microorganisms inlcuding the A. niger and Trichoderma sp. were observed to produce antifungal substances which tended to restrict the development and

growth of other fungi on the Malt Extract Agar in the Petri dishes. These two fungi could be further studied for biological control strategies for A. flavus

group of fungi and other fungi which would contaminate groundnuts and processed groundnuts with aflatoxins and other hazardous mycotoxins.

Twenty groundnut seed samples out of the total 24 which were purchased in this survey had infections of the A. flavus group of fungi which were above

50%. Samples no. 6, 8, 10, 13, 14, 16, 18, 20, 24 and 27 had infections ranging from 78-89%. This therefore indicates that the groundnut varieties which

farmers grow and which traders sell to consumers in Malawi are highly susceptible to seed invasion by A. flavus group of fungi and thus they are

vulnerable to aflatoxin and other mycotoxin contamination. There is an urgent need to devise means of analysing other mycotoxins other than aflatoxins.

MOISTURE CONTENT IN THE GROUNDNUTS AND PROCESSED

GROUNDNUTS

The results of the percent seed moisture content determination in the groundnuts and processed groundnuts are presented in Table 2.

The percent seed moisture content ranged from 2.1 - 8.1%. The safe moisture content for groundnut seed is 8.0% so that all the samples were below the

recommended safe seed moisture content. The low seed moisture content was due to the over-drying of the groundnut pods as mentioned in the

introduction of this document. This low seed moisture content is the one which leads farmers to moisten their groundnuts to make up for the very low

moisture content because farmers sell their groundnuts to traders by weight. This remoistening of the groundnut pods is not recommended because it

encourages the infections of the A. flavus and the likely contamination of the seed with aflatoxins. The farmers should be educated on the proper

procedures for harvesting, drying and storage of their groundnuts in Malawi.

TOTAL AFLATOXIN B1 CONTENT IN THE GROUNDNUTS AND

PROCESSED GROUNDNUTS IN MALAWI

The results of the total aflatoxin B1 content in the 29 samples purchased from farmers and traders are presented in Table 2.

The total aflatoxin B1 content ranged from 0 to 4.0 ng.g.-1

. Samples no. 4 and 8 from Ntcheu R.D.P, samples no. 9 and 13 from Thiwi/Lifidzi R.D.P., sample no. 15 from Dedza R.D.P., and sample no. 19 from Lilongwe West R.D.P. had low total aflatoxin B1 content which ranged from 0.4 - 4.0 ng.g.

-1.

The sample with the total aflatoxin B1 content of 4.0 ng..g-1

comprised of groundnut meal purchased from a trader at a local market in Ntcheu. According

to the information obtained from the survey the trader originally purchased the groundnuts from Mozambique and grew them in her garden. At the time of

the interview she was selling both groundnut seed and groundnut meal which were from her homestead. However, the total aflatoxin B1 content in the

groundnut meal was far below the critic level of 10 - 20ng.g-1

when aflatoxins cause fatal liver cancer in young animals.

Twenty one percent of the 29 samples had low total aflatoxin B1 content so that these samples had very low total aflatoxin B1 content that they did not pose

any health hazard to consumers.

CONCLUSIONS

The 21% of the groundnuts and processed groundnuts which had a low total aflatoxin B1 content which ranged from 0.4 - 4.0 ng.g-1

did not pose a health

hazard to consumers in Malawi.

However, the sample size of 29 was too small and insufficient to reflect the true picture of the aflatoxin contamination problem in groundnuts and

processed groundnuts in Malawi. More samples of groundnuts and processed groundnuts should have been bought from farmers and traders and processors

and etc. Unfortunately, more samples could not be bought because of the following reasons:

1. We experienced delays with the encashment of the Dollar cheques once they had been issued. This was because once the Dollar cheque was deposited at

the Reserve Bank of Malawi; it was returned to the issuing Bank in Georgia, U.S.A. for the cheque to clear before it could be encashed in Malawi. For

example, the cheque took 6 (six) months from the time a financial report was dispatched by DHL Express Mail to the U.S.A. to the time the money became

available in the ledger for use on project activities in Malawi.

2. Most of the money was spent on the manufacture of the fibre-glass cylinders for the mini plots to be used later for screening groundnut genotypes for

resistance to A. flavous.

3.Non-availability of a reliable vehicle for conducting the survey. When a Malawi Government vehicle was provided for use on project activities, a considerable amount of money was spent to repair the dilapidated vehicle so that it could be roadworthy. As a result a limited number of samples of

groundnuts and processed groundnuts was purchased. Funds were not available for us to continue the purchase of more samples.

FUTURE PLANS

We plan to purchase a minimum of 100 samples of groundnuts and processed groundnuts from the smallholder farmers, traders, processors and etc. We

will do this by spending more money on the survey then on the manufacture of the fibreglass cylinders which we hope will finish towards the beginning of

the 1999/2000 crop growing season sometime in October 1999.

Table 1: Passport Data of Farmers and Traders Interviewed in the Survey of the Aflatoxin Contamination Problem in Groundnuts and Processed

Groundnuts in Malawi in the 1997/98 Crop Growing Season

Sample

No. Name of Farmer or

Trader Town or Village Traditional

Authority District E.P.A. R.D.P. A.D.D. Name of Groundnut

Cultivar or Variety 1 Stella Goliati Kadzakalowa Njolomole Ntcheu Njolomole Ntcheu Lilongwe Kalisere 2 Esther Bizaye Eneya

(Ntcheu Market)

Kwataine Ntcheu Nsipe Ntcheu Lilongwe Mixed Varieties

3 Agnes Chanamuna Chinyamula (Ntcheu

Market) Kwataine Ntcheu Nsipe Ntcheu Lilongwe Kalisere

4 Agnes Chanamuna Chinyamula (Ntcheu

Market) Kwataine Ntcheu Nsipe Ntcheu Lilongwe Groundnut Meal

5 Ms. Ndanga Fuko Njolomole Ntcheu Njolomole Ntcheu Lilogwe Kalisere 6 Mary Biliati Nsiyaludzu Kwataine Ntcheu Nsipe Ntcheu Lilongwe Chalimbana 7 Davide Mathola Magombo Makwangwala Ntcheu Nsipe Ntcheu Lilongwe Kalisere 8 Mpeketula

Divaisoni Jingo (Bwanje

Market) Ganya Ntcheu Kandeu Ntcheu Lilongwe Chalimbana

9 Manjakaitse Mlangali Pemba Dedza Lobi Thiwil

Lfidzi Lilongwe Mixed Varieties

10 Manjakaitse Mlangali Pemba Dedza Lobi Thiwi

Lifidzi Lilongwe Mixed Varieties

11 Ms. Nyabuyi Chamapenga (Lobi) Pemba Dedze Lobi Thiwi

Lifidzi Lilongwe Peanut Butter

12 Ms. Nyabuyi Chamapenga (Lobi) Pemba Dedza Lobi Thiwi

Lifidzi Lilongwe Peanut Butter

Table 1 Continued

Sample

No. Name of Farmer or

Trader Town or Village Traditional

Authority District E.P.A. R.D.P. A.D.D. Name of Groundnut

Cultivar or Variety 13 Weluzani

Mbewe

Maonde (Dedza

Market) Pemba Dedza Lobi Thiwi

Lifidzi

Lilongwe Kalisere

14 Elise Fatere Njolomole

(Linthipe

2Market)

Kaphuka Dedza Kaphuka Dedza

Hills

Lilongwe Kalisere

15 Ms.

Likiyana

Kaunda

(Linthipe

2Market)

Kaphuka Dedza Kaphuka Dedza Hills Lilongwe Chalimbana

16 Saidi Ngozo Makwinja

(Nkhoma Market)

Mazengera Lilongwe Mpenu Lilongwe

East Lilongwe Mixed varieties

17 Saidi Ngozo Makwinja

(Nkhoma Market)

Mazengera Lilongwe Mpenu Lilongwe

East Lilogwe Mixed Varieties

18 Mrs. J.

Mbandambanda Chinsapo

(Lilongwe Market)

Njewa Lilongwe Chitipi Lilongwe

West Lilongwe Mixed Varieties

19 Mrs.

Thawani

Chigwirizano

(Lilongwe Market) Njewa Lilongwe Kalima Lilongwe

West Lilongwe Groundnut Meal

20 V. Phuka Chinsapo

(Lilongwe Market)

Njewa Lilongwe Chitipi Lilongwe

West Lilongwe Mixed Varieties

21 Edwin Likoloma Lilongwe City

(Area 25A)

Chimutu Lilongwe Lumbadzi Lilongwe

East Lilongwe Kalisere

Table 1 Continued

Sample

No. Name of Farmer

or Trader Town or

Village Traditional

Authority District E.P.A. R.D.P. A.D.D. Name of

Groundnut

Cultivar or Variety

22 Mrs.

Stephano

Lilongwe City

(Area 25B)

Chimutu Lilongwe Lumbadzi Lilongwe East Lilongwe Groundnut

Meal

23 Thomas

Mvunguti

Lilongwe City

(Street

Vendor)

Njewa Lilongwe ? Lilongwe West Lilongwe Mixed

Varieties

24 Kandodo Main

Shop Lilongwe City

(Old Town)

Njewa Lilongwe ? Lilongwe West Lilongwe Kalisere

25 Peoples Trading

Cntre (P.T.C.)

Hyperstore Lilongwe

City

(Old Town)

Njewa Lilongwe ? Lilongwe

West

Lilongwe Peanut

Butter

26 Mrs. Makwalu Kawale

Market Tsabango Lilongwe Chiwamba Lilongwe East Lilogwe Chalimbana

27 Mrs. Nello Kawale

Market Tsabango Lilongwe Chiwamba Lilongwe East Lilongwe Chalimbana

28 Zenus Chilima Kawale

Market Tsabango Lilongwe Chiwamba Lilongwe East Lilongwe Kalisere

29 Dzikondianthu

Phinifolo Kawale

Market

Tsabango Lilongwe Chiwamba Lilongwe

East

Lilongwe Chalimbana

Note: E.P.A. = Extension Planning Area;

R.D.P. = Rural Development Project

A.D.D. = Agricultural Development Division

Table 2: Seed moisture Content, Aspergillus flavus Group of Fungi and Other Mycoflora Isolations and Quantitative

Aflatoxin Assays of Groundnut and Processed Groundnut Samples Bought from Farmers and Traders in

Malawi in the 1997/98 Crop growing Season

Sample

No. Sample

Source

(R.D.P.)

Groundnut

Cultivar or

Variety

Seed moisture

Content (%) Aspergillus flavus

Isola-tions (%) Other Resident

Mycoflora Isolations

from Seed

Total Aflatoxin

B1 Content

(ng.g-1

)

Aflatoxin Level

(Low, Medium or

High)

1 Ntcheu Kalisere 6.5 49 1. Fusarium spp.

2. Rhizopus sp.

3. Penicillium spp.

4. Trichoderma sp.

5. Aspergillus niger

0 -

2 Ntcheu Mixed Varieties 5.0 67 1. Fusarium spp.

2. Rhizopus sp.

3. Penicillium spp.

4. Trichoderma sp.

5. Aspergillus niger

0

-

3 Ntcheu Kalisere 2.4 65 1. Fusarium spp.

2. Rhizopus sp.

3. Penicillium spp.

4. Trichoderma sp.

5. Aspergillus niger

0

-

4 Ntcheu Groundnut Meal 3.4 - - 4.0 Low

Table 2: Continued

Sample

No. Sample

Source

(R.D.P.)

Groundnut

Cultivar or

Variety

Seed moisture

Content (%) Aspergillus flavus

Isola-tions (%) Other Resident

Mycoflora Isolations

from Seed

Total Aflatoxin

B1 Content

(ng.g-1

)

Aflatoxin Level

(Low, Medium or

High)

5 Ntcheu Kalisere 4.1 57 1. Fusarium spp.

2. Rhizopus sp.

3. Penicillium spp.

4. Trichoderma sp.

5. Aspergillus niger

0

-

6 Ntcheu Chalimbana 2.1 81 1. Fusarium spp.

2. Rhizopus sp.

3. Penicillium spp.

4. Trichoderma sp.

5. Aspergillus niger

0

-

7 Ntcheu Kalisere 3.0 72 1. Fusarium spp.

2. Rhizopus sp.

3. Penicillium spp.

4. Trichoderma sp.

5. Aspergillus niger

0

-

8 Ntcheu Chalimbana 5.0 78 1. Fusarium spp.

2. Rhizopus sp.

3. Penicillium spp.

4. Trichoderma sp.

5. Aspergillus niger

2.0

Low

Table 2: Continued

Sample

No. Sample

Source

(R.D.P.)

Groundnut

Cultivar or

Variety

Seed moisture

Content(%) Aspergillus flavus

Isola-tions (%) Other Resident

Mycofloral Isolations

from Seed

Total

Aflatoxin

B1 Content

(ng.g-1

)

Aflatoxin Level

(Low, Medium or

High)

9 Thiwi Lifidzi Mixed Varieties 4.0 66 1. Fusarium spp.

2. Penicillium spp.

2.0

Low

3. Trichoderma sp.

4. Aspergillus niger 10 Thiwi Lifidzi Mixed Varieties 7.0 79 1. Fusarium spp.

2. Penicillium spp.

3. Trichoderma sp.

4. Aspergillus niger

0

-

11 Thiwi Lifidzi Mixed Varieties 7.0 71 1. Fusarium spp.

2. Rhizopus sp.

3. Penicillium spp.

4. Trichoderma sp.

5. Aspergillus niger

0

-

12 Thiwi Lifidzi Peanut Butter 8.0 - - 0 -

13 Thiwi Lifidzi Kalisere 7.9 88 1. Fusarium spp.

2. Penicillium spp.

3. Aspergillus niger

0.8 Low

14 Dedza Hills Kalisere 5.7 81 1. Fusarium spp.

2. Penicillium spp.

3. Aspergillus niger

0 -

Table 2: Continued

Sample

No. Sample

Source

(R.D.P.)

Groundnut

Cultivar or

Variety

Seed moisture

Content(%) Aspergillus flavus

Isola-tions (%) Other Resident

Mycoflora Isolations

from Seed

Total Aflatoxin

B1 Content

(ng.g-1

)

Aflatoxin Level

(Low, Medium or

High)

15 Dedzai Chalimbana 8.1 44 1. Fusarium spp.

2. Aspergillus niger

3. Trichoderma sp.

4. Penicillium spp

2.0 Low

16 Lilongwe

East Mixed Varieties 5.3 85 1. Fusarium spp.

2. Penicillium spp.

3. Aspergillus niger

4. Trichoderma sp.

0

-

17 Lilogwe East Mixed Varieties 4.5 71 1. Trichoderma sp. 0

-

2. Aspergillus niger

3. Penicillium spp.

4. Fusarium spp. 18 Lilongwe

West Mixed Varieties 5.0 82 1. Trichoderma sp.

2. Aspergillus niger

3. Fusarium spp.

4. Penicillium spp.

0 -

19 Lilongwe West Groundnut Meal 4.0 - - 0.4 Low

Table 2: Continued

Sample

No. Sample

Source

(R.D.P.)

Groundnut

Cultivar or

Variety

Seed moisture

Content(%) Aspergillus flavus

Isola-tions (%) Other Resident

Mycoflora Isolations

from Seed

Total Aflatoxin

B1 Content

(ng.g-1

)

Aflatoxin Level

(Low, Medium or

High)

20 Lilongwe

West Mixed Varieties 4.3 89 1. Aspergillus niger

2. Rhizopus sp.

3. Fusarium spp.

4. Penicillium spp

5. Trichoderma sp

0

-

21 Lilongwe

East Kalisere 2.1 69 1. Aspergillus niger

2. Trichoderma sp.

3. Fusarium spp.

4. Penicillium spp.

0

-

22 Lilogwe East Groundnut Meal 4.4 - - 0 - 23 Lilongwe

West Mixed Varieties 5.2 39 1. Fusarium spp.

2. Aspergillus niger

3. Penicillium spp.

4. Trichoderma sp.

5. Rhizopus sp.

0

-

24 Lilongwe West Kalisere 2.8 79 1. Aspergillus niger 0

-

2. Fusarium spp.

3. Penicillium spp.

4. Rhizopus sp.

5. Trichoderma sp.

Table 2: Continued

Sample

No. Sample

Source

(R.D.P.)

Groundnut

Cultivar or

Variety

Seed moisture

Content (%) Aspergillus flavus

Isola-tions (%) Other Resident

Mycoflora Isolations

from Seed

Total Aflatoxin

B1 Content

(ng.g-1

)

Aflatoxin Level

(Low, Medium or

High)

25 Lilongwe

West Peanut Butter 3.0 - - 0 -

26 Lilongwe East Chalimbana 4.3 50 1. Aspergillus niger

2. Fusarium spp.

3. Penicillium spp.

4. Rhizopus sp.

5. Trichoderma sp.

0

-

27 Lilogwe East Chalimbana 4.3 86 1. Aspergillus niger

2. Fusarium spp.

3. Penicillium spp.

4. Trichoderma sp.

0

-

28 Lilongwe East Kalisere 4.0 39 1. Fusarium spp.

2. Penicillium spp.

3. Aspergillus niger

4. Trichoderma sp.

0

-

29 Lilongwe East Chalimbana 5.3 46 1. Fusarium spp.

2. Aspergillus niger

3. Trichoderma sp.

0

-

4. Penicillium spp.

5. Rhizopus sp.

Note: R.D.P. = Rura Development Project; % = Percent;

ng.g-1

= Nanogramme per Gramme

sp. = Species; Spp. = species (Plural).

APPENDIX I:

QUESTIONNAIRE FOR CONDUCTING THE SURVEY OF THE

AFLATOXIN CONTAMINATION PROBLEM IN GROUNDNUTS AND

PROCESSED GROUNDNUTS IN MALAWI

Date of Visit: ...................................

1. Name of Farmer/Trader:

2. Village/Town:

3. Chief: (TA or Sub TA):

4. District:

5. Name of field Assistant:

6. Agricultural Extension Section:

7. Extension Planning Area (E.P.A.):

8. Rural Development Project (R.D.P.):

9. Agricultural Development Division:

10. Groundnut Cultivar Grown by Farmer:

11. Origin of Seed:

12. Sowing Date:

13. Harvest Date:

14. Method of Harvesting or Lifting:

15. Method of Curing or Drying:

16. Stripping of Pods (Mature or Immature or Rotten):

17. Method of Determining Dryness of the Pods:

18. Handling of Pods After Drying Prior to Storage:

19. Determination of Yield per Acre/Hectare:

20. Method of Storage:

21. Place of Storage:

22. Diseases and Pests Observed in Place of Storage:

23. Management of Diseases and Pests in Place of Storage:

24. Utilization of Groundnuts:

24.1) For sale to: 24.1.1): ADMARC

24.1.2): Neighbours at Local Markets

24.2) For Home consumption:

24.3.1): As Seasoning for Vegetable Dishes

24.3.2): Eaten Raw or Unprocessed

24.3.3): Roasted and Eaten as Snack

24.3) For seed

24.4) For Livestock feed

24.5) Other (Please Specify)

25. Other Crops Cultivated by Farmer:

26. Number of years farmer has been cultivating groundnuts"

27. Problems farmer experiences with groundnut cultivation:

28. How farmer thinks his groundnut cultivation problems can be alleviated:

29. Inspection and photographing of the groundnut storage structure:

30. Interview ends with the purchase of 5.0 kilograms of dry unshelled groundnuts and 2.0 kilograms of processed groundnuts.

B. REPORT OF THE SCREENING OF GROUNDNUT GENOTYPES

FOR STABILITY OF RESISTANCE TO INFECTION BY

Aspergillus flavus UNDER FIELD CONDITIONS IN MALAWI

I. INTRODUCTION

Most scientists agree that if the aflatoxin contamination problem can be prevented before storage (pre-harvest) then the problem can be successfully

managed.

Management strategies for minimizing or eliminating aflatoxin contamination begin in the field and end with the manufacturer/processor. The aflatoxin

problem can be described as a pre-harvest problem, a harvesting and drying problem, and a warehousing and utilization problem. Each of these phases is a

separate problem and each provides a different environment for creating a favourable habitat for the infections of the Aspergillus flavus group of fungi to

occur. Management of pre-harvest contamination at present must rely on production practices. There is at present no single practice that can prevent

aflatoxin contamination of groundnuts in Malawi. However, if we could breed varieties of groundnuts upon which the aflatoxigenic A. flavus group of

fungi could not grow or on which they could grow but could not produce aflatoxins, then the problem would be solved. Unfortunately there are no

groundnut varieties resistant to either A. flavus group of fungi infections or aflatoxin production once infection has already occurred. Groundnut genotypes

resistant to infections by A. flavus group of fungi and the subsequent aflatoxin contamination of the commodity are reported to be available in the U.S.A.

and at ICRISAT Asia Centre and elsewhere. But these genotypes have not been screened for stability of resi stance to the infections by A. flavus group of

fungi and aflatoxin contamination under field conditions in Malawi.

Therefore, one of the main research objectives of the Aflatoxin Research Project on Groundnuts in Malawi is to screen groundnut genotypes for stability of

resistance to infection by A. flavus under field conditions.

The research activities to be done under this important objective were as follows:

1. To conduct groundnut aflatoxin field trials at sites with different environmental conditions. These sites were: Chitedze, Chitala and Makoka Agricultural

Research Stations.

2. To screen groundnut genotypes for stability of resistance to infection by A. flavus under artificial inoculation of the plants in field mini plots with or

without rainout shelters at Chitedze.

This research activity involves the manufacture of fibreglass cylinders and the construction of the mini plots and rainout shelters to be located only at

Chitedze.

II. MATERIALS AND METHODS

The sites for the groundnut aflatoxin field trials were chosen so that each site had different environmental conditions. Therefore, the sites chosen were as

follows:

1. Chitedze Agricultural Research Station which was on the plateau with cool and wet conditions in the rainy season which were unfavourable to infections

by A. flavus group of fungi. Chitedze is also located in the major groundnut producing areas in Malawi.

2. Chitala Agricultural Research Station which is located on the rift valley escarpment and has warm and humid conditions. These conditions are very

favourable to infections of groundnuts by A. flavus group of fungi in the field.

3. Makoka Agricultural Research Station is located on the Shire Highlands and has warm and wet conditions in the rainy season. These conditions are

probably conducive and favourable to infections of groundnuts by A. flavus group of fungi in the field but the wet conditions could be unfavourable at this

site.

The design of the trials was randomized complete blocks. The trial at Chitedze had 25 entries with three replicates while the trial at Chitala had 10 entries

and four replicates. The trial at Makoka had 10 entries with five replicates. The size of the gross plots at Chitedze and Chi tala was 6.0 metres long x 4

ridges spaced at 0.6 metre while at Makoka the gross plots were 6.0 metres long x 4 ridges spaced at 0.75 metre. The nett plots at all the sites were 5.0

metres long x 2 ridges in the middle.

Seed were sown according to the recommended practices for sowing the long -, medium - and short - duration varieties included in the trials.

When the various groundnut genotypes attained their respective physiological maturity stage, the plants from the nett plots which comprised of 5.0 metres

long x 2 ridges were dug up with a hand hoe and the fresh pods stripped by hand. The fresh pods were spread on clean mats to dry in the sun and were

removed and kept in the laboratory overnight. This was done for 10 days continuously.

The data collected from all the groundnut aflatoxin field trials were as follows:

1. Soil samples collected at 15cm depth (top soil) and 30cm depth (sub soil) for a full chemical analysis before sowing.

2. Rainfall distribution data and other useful weather data.

3. Plant stand counts in gross plots at emergence.

4. Weekly scores of foliar fungal diseases using the ICRISAT modified 1 - 9 point score scale on gross plots.

5. Weekly counts of diseased plants per gross plots (e.g. rosette and other viral diseases).

6. Weekly counts of plants damaged by arthropod pests such as termites and planthoppers (Hilda patruelis).

7. Records of drought (water stress) conditions at weekly intervals on the 1- 5 point score scale where:

1 = No water stress

2 = Slight water stress

3 = Moderate water stress

4 = Severe water stress

5 = Very severe water stress

8. AT HARVEST TIME

To record the following parameters on fresh pods from nett plots:

1). Total number of pods

2). Number of sound pods

3). Number of scarified pods

4). Number of immature pods

6). Weight of fresh haulms.

7). Weight of dry haulms.

9. To dry the fresh pods and to carefully crack the dry pods and count the kernels as follows:

1). Number of good kernels

2). Number of broken (split) kernels

3). Number of shrivelled kernels

4). Number of rotten kernels

10. Soil samples to be collected at 15cm (top soil) for isolations of propagules of the Aspergillus flavus group of fungi.

11. Soil samples collected at 15cm depth (top soil) and 30cm (sub soil) for a full chemical analysis at harvest.

III. RESULTS AND DISCUSSION

Data recorded from the Groundnut Aflatoxin field Trial conducted at Chitedze are presented in Tables 1a and 1b. The data on the mycological tests

conducted in the Groundnut Pathology Laboratory and the quantitative analysis for aflatoxin contamination on the groundnut kernel samples from the trial

conducted at Chitedze are presented in Table 1c.

Data recorded from the Groundnut Aflatoxin field Trial conducted at Chitala are presented in Tables 2a and 2b. The data on the mycological tests and

aflatoxin analysis on the samples from Chitala are presented in Table 2c.

Data recorded from the trial ran at Makoka are presented in Tables 3a and 3b while the data on the mycological tests and aflatoxin analysis are presented in

Table 3c.

A. CHITEDZE

The groundnut plant stand count at emergence was very good with no major variations in the groundnut genotypes. This could have been due to the good

rainfall which was received at this site at the beginning of the crop growing season. The stand count at harvest was also good for all the groundnut

genotypes used in the trial (Table 1a).

The early leaf spot disease was generally high on all the groundnut genotypes because the Chitedze site is an area where this disease is serious every crop

growing season and also no disease management practices were used to reduce or eradicate this disease in the trial. Since no disease management practices

were used defoliation in all the groundnut genotypes was high (Table 1a).

The occurrence of rosette, termites and plant hoppers in the trial was scattered and unpredictable and therefore there was no effect of the groundnut

genotypes on these constraints at Chitedze (Table 1a).

The number of good nuts from good pods was generally highest followed by shrivelled nuts and the next category was the rotten nuts while the broken nuts

category was least in number. The food nuts were consistently obtained or recovered from the immature nuts category fol lowed by the shrivelled nuts

category. Good nuts were recovered from rotten pods while the highest proportion of rotten nuts comprised of rotten nuts. A high proportion of good nuts

was obtained from both mechanically damaged and termites scarified groundnut pods categories. The apparently good nuts which were recovered from

termite scarified pods, immature pods and rotten pods categories are definitely a source of aflatoxin contaminated groundnuts. This is because in Malawi

consumers would reject apparently or visibly rotten nuts but they accept and eat the visibly sound nuts irrespective of the source i.e. even if the good nuts

were mixed with damaged and shrivelled and rotten nuts such sound nuts would unknowingly be consumed (Table 1b).

People should be educated to desist from consuming raw visibly sound groundnuts from mechanically damaged, termite scarified, immature and rotten

pods. People should also be educated to reject and avoid the consumption of nuts which are broken, shrivelled and rotten.

All the groundnuts genotypes tested were susceptible to mechanical damage, termite scarification, they produced immature forms of pods and were

probably susceptible to pod borers and pod rotting fungi which led to a high proportion of rotten pods being obtained in the trial at Chitedze (Table 1b).

Generally, there were very few broken, shrivelled and rotten nuts from mechanically damaged, termite scarified and immature pods. Few broken and

shrivelled nuts were obtained from rotten pods (Table 1b). No interaction was obtained between the groundnut genotypes and the condition of the pods at

Chitedze (Table 1b). This indicated that the categories of the nuts which were obtained from the various conditions of the pods were not dependent on the

groundnut genotypes used in the trial at Chitedze.

At Chitedze the % seed moisture content ranged from 3.1 - 6.2% (Table 1c). The safe % seed moisture content for groundnuts is 8.0% and therefore all the

seed from the trial were at a very safe seed moisture content.

The % isolations of the Aspergillus flavus groups of fungi ranged from 18 - 85% (Table 1c). The groundnut genotypes were highly susceptible to infections by the aflatoxin producing fungi under field conditions at Chitedze. The aflatoxin B1 content at Chitedze ranged from 0.7 - 2.7ng.g

-1. This level of aflatoxin

content represented a negligible level which does not pose a serious health risk to consumers in Malawi. Although the groundnut genotypes tested at

Chitedze had negligible aflatoxin B1 content, they were nonetheless seriously infected by other resident seed microorganisms which included the following

in order of profuseness of isolations:

1. Fusarium spp.

2. Aspergillus niger

3. Penicillium spp.

4. Trichoderma sp.

5. Rhizopus stolonifer

CURRENT STATUS OF THE CONSTRUCTION OF THE FIBREGLASS MINI PLOTS AND RAINOUT SHELTERS AT CHITEDZE

We need to finalize the construction of the fibreglass cylinders and the fixing of the cylinders in the field. However, curre ntly we consider this not to be a

priority research activity because in this part of the world the groundnut crop is already very advanced. Most of the groundnut plants are flowering.

Therefore, the screening of groundnut genotypes in the mini plots will commence from next season in the 1999/2000.

We already have 75 (seventy five) fibreglass cylinders fixed in the field and we are remaining with 25 cylinders to be manufactured and placed in the field.

The manufacturer of the fibreglass cylinders in Blantyre is first of all waiting for us to prepay for the manufacture of the remaining cylinders so that he can

travel to Zimbabwe and purchase the raw materials for the 25 cylinders. The manufacturer of the cylinders has already informed me that the cost of both

the raw materials and the manufacture of the cylinders will increase. This is mainly because of inflation in Malawi and Zimbabwe.

We have decided not to spend any money from the current funding on the construction of cylinders. This is because we need the money to conduct the

groundnut aflatoxin field trials at Chitedze, Chitala and Makoka Agricultural Research Stations. We will also use the money for monitoring the field trials.

We will use some money for paying wages and salaries for casual labourers and technicians respectively. A proportion of the money will be used for

purchasing supplies for laboratory use.

Meanwhile, we have grown 25 groundnut genotypes in the mini plots. These groundnuts genotypes are those which are grown in the aflatoxin field trial at

Chitedze. These groundnut genotypes have been grown in the mini plots in order to increase the seed for future use and also to observe how they perform

in the mini plots under the Malawi field conditions. In a way we wanted to make good use of the mini plots this season instead of just leaving the fibreglass

cylinders stand in the field without being used at all until the 1999/2000 crop growing season when the experiment will commence.

C. REPORT OF THE TRAINING COURSES ON THE AFLATOXIN

CONTAMINATION PROBLEM IN GROUNDNUTS AND PROCESSED GROUNDNUTS IN MALAWI

No training courses were conducted in the period August 07, 1997 to January end, 1999.

The training courses for the Technical Assistants (T.A.s), Field Assistants (F.A.s), Traders and Processors are planned to be conducted later on towards the

end of the Aflatoxin Research Project on Groundnuts in Malawi.

The following activities are planned to be done in order to achieve the aims of this objective on training:

1. To develop training course manuals and booklets suitable for trainees engaged in groundnut production, trading, and processing, and utilization in

Malawi.

2. To conduct 3 (three) training courses in order to create awareness in the following groups of trainees:

1). Technical Assistants (T.A.s) whom we hope will impart and impact the knowledge gained from the course to research scientists in Malawi.

2). Field Assistants (F.A.s) whom we hope will impart and impact the knowledge gained from the course on to farmers in Malawi.

3). Traders and Processors whom we hope will appreciate the risks and how to avoid the aflatoxin contamination problem in groundnuts and processed

groundnuts especially in their respective work places and the entire groundnut trade in Malawi.

TABLE 1a: PLANT STAND COUNTS AT EMERGENCE AND AT HARVEST, MEAN EARLY LEAF SPOT AND DEFOLIATION SCORES,

ROSETTE, TERMITES AND PLANT-HOPPER DAMAGED PLANT COUNTS RECORDED FROM THE GROUNDNUT AFLATOXIN

FIELD TRIAL CONDUCTED AT CHITEDZE IN THE 1997/98 CROP GROWING SEASON

GROUNDNUT

GENOTYPES

STAND COUNT

AT

EMERGENCE

(PLANTS PER

HA. IN '000)

STAND

COUNT AT

HARVEST

(PLANTS

PER HA. IN

1000)

MEAN

EARLY

LEAF

SPOT

SCORES

(1-9)

MEAN

DEFOLIATION

SCORES (1-9)

ROSETTE

DAMAGED

PLANT

COUNTS

(PLANTS PER

HA. IN 1000)

TERMITES

DAMAGED

PLANT

COUNTS

(PLANTS PER

HA.)

PLANT

HOPPER

DAMAGED

PLANT

COUNTS

(PLANTS PER

HA.) ICGV 89104 152 145 6 6 8 232 694 ICGV 91278 150 129 6 5 4 232 231 ICGV 91284 147 146 5 5 3 463 231 ICGV 91289 154 144 5 5 10 463 0 ICGV 91290 154 149 6 5 3 0 0 ICGV 91298 154 152 6 5 6 0 0 ICGV 91305 158 147 5 4 2 0 231 ICGV 91317 145 143 5 4 4 0 0 ICGV 91322 153 139 5 4 1 0 0 ICGV 91323 145 140 5 4 4 0 0 ICGV 91324 135 135 6 5 0 231 0 ICGV 91328 153 137 5 5 1 231 0

Table 1a: Continued

GROUNDNUT

GENOTYPES

STAND COUNT

AT

EMERGENCE

(PLANTS PER

HA. IN 1000)

STAND

COUNT AT

HARVEST

(PLANTS

PER HA. IN

1000)

MEAN

EARLY

LEAF

SPOT

SCORES

(1-9)

MEAN

DEFOLIATION

SCORES

(1-9)

ROSETTE

DAMAGED

PLANT

COUNTS

(PLANTS PER

HA. IN 1000)

TERMITES

DAMAGED

PLANT

COUNTS

(PLANTS PER

HA.)

PLANT

HOPPER

DAMAGED

PLANT

COUNTS

(PLANTS PER

HA.) ICGV 91334 169 152 6 6 13 926 0 J 11 144 140 5 5 1 0 0

JL 24 154 137 4 3 0 0 0 UF 71513-1 146 141 6 5 5 0 0 ICGV 91329 144 144 4 5 1 0 0 MALIMBA 145 129 5 5 3 231 0 BEBIANO BRANCO 160 154 6 5 1 463 231 ICGMS # 5 150 132 4 3 21 0 0 SELLIE 154 143 6 5 3 231 0 CG 7 104 104 3 2 2 0 231 NATAL COMMON 148 140 6 5 4 0 463

Table 1a: Continued

GROUNDNUT

GENOTYPES

STAND COUNT

AT EMERGENCE

(PLANTS PER

HA. IN '000)

STAND

COUNT AT

HARVEST

(PLANTS PER

HA. IN '000)

MEAN

EARLY

LEAF

SPOT

SCORES

(1-9)

MEAN

DEFOLIA-

TION

SCORES(1-

9)

ROSETTE

DAMAGED

PLANT

COUNTS

(PLANTS PER

HA. IN '000)

TERMITES

DAMAGED

PLANT

COUNTS

(PLANTS PER

HA.)

PLANT

HOPPER

DAMAGED

PLANT

COUNTS

(PLANTS PER

HA.)

COMENT 159 159 6 5 1 0 0 SWALLOW 144 136 4 3 8 463 231 TRIAL MEANS 149 142 5 4 4 167 102 S.E. + 8.0 7.4 0.2 0.3 4.4 275.2 158.7

C.V. (%) 9.32 9.10 7.79 12.80 0.18 285.99 269.87 SIGNIFICANCE ** ** *** *** NS NS NS

TABLE 1b: RECORD OF COUNTS OF GOOD, BROKEN, SHRIVELLED AND ROTTEN SEED FROM THE GOOD, DAMAGED, TERMITE

SCARIFIED, IMMATURE AND ROTTEN PODS FROM THE GROUNDNUT AFLATOXIN FIELD TRIAL CONDUCTED AT CHITEDZE IN

THE 1997/98 CROP GROWING SEASON

CONDITION OF THE GROUNDNUT SEED

GROUNDNUT

GENOTYPES CONDITION OF THE

GROUNDNUT PODS GOOD

(NO. PER

SAMPLE)

BROKEN (NO. PER

SAMPLE) SHRIVELLED (NO. PER

SAMPLE) ROTTEN

(NO. PER

SAMPLE)

GOOD 1661 2 304 28 MECHANICALLY 20 3 3 1

ICGV 89104

DAMAGED TERMITE SCARIFIED 23 1 6 3 IMMATURE 157 0 60 7 ROTTEN 32 1 25 76

ICGV 91278

GOOD 1624 3 195 10 MECHANICALLY

DAMAGED

6 6 2 0

TERMITE SCARIFIED 38 0 3 3 IMMATURE 25 0 48 9 ROTTEN 21 0 8 36

ICGV 91284

GOOD 1368 1 170 18 MECHANICALLY

DAMAGED

12 1 3 1

TERMITE SCARIFIED 13 1 3 2 IMMATURE 43 0 29 5 ROTTEN 17 1 6 23

Table 1b: Continued

CONDITION OF THE GROUNDNUT SEED

GROUNDNUT

GENOTYPES CONDITION OF THE

GROUNDNUT PODS GOOD

(NO. PER

SAMPLE)

BROKEN (NO. PER

SAMPLE) SHRIVELLED (NO. PER

SAMPLE) ROTTEN (NO. PER

SAMPLE)

ICGV 91289

GOOD 1568 1 219 10 MECHANICALLY

DAMAGED

1 0 0 0

TERMITE SCARIFIED 8 0 0 0 IMMATURE 57 0 33 6 ROTTEN 22 0 9 39

ICGV 91290

GOOD 1295 5 165 5 MECHANICALLY

DAMAGED

3 1 0 0

TERMITE SCARIFIED 20 0 2 1 IMMATURE 26 0 23 2 ROTTEN 15 1 7 37

ICGV 91298

GOOD 1632 2 300 3 MECHANICALLY

DAMAGED

20 7 2 1

TERMITE SCARIFIED 18 0 1 5 IMMATURE 36 0 33 3 ROTTEN 14 1 4 50

Table 1b: Continued

CONDITION OF THE GROUNDNUT SEED

GROUNDNUT

GENOTYPES CONDITION OF THE

GROUNDNUT PODS GOOD

(NO. PER

SAMPLE)

BROKEN (NO. PER

SAMPLE) SHRIVELLED (NO. PER

SAMPLE) ROTTEN

(NO. PER

SAMPLE)

ICGV 91305

GOOD 1434 2 109 1 MECHANICALLY

DAMAGED

9 3 1 0

TERMITE SCARIFIED 26 0 2 3 IMMATURE 28 0 21 1 ROTTEN 13 0 3 24

ICGV 91317

GOOD 1309 1 197 2 MECHANICALLY

DAMAGED

4 3 1 1

TERMITE SCARIFIED 9 0 0 1 IMMATURE 33 0 65 3 ROTTEN 11 0 3 8

ICGV 91322

GOOD 1301 2 163 15 MECHANICALLY

DAMAGED

4 4 0 1

TERMITE SCARIFIED 19 0 3 1 IMMATURE 42 0 42 8 ROTTEN 13 0 7 23

Table 1b: Contunued

CONDITION OF THE GROUNDNUT SEED

GROUNDNUT

GENOTYPES CONDITION OF THE

GROUNDNUT PODS GOOD

(NO. PER

SAMPLE)

BROKEN (NO. PER

SAMPLE) SHRIVELLED (NO. PER

SAMPLE) ROTTEN

(NO. PER

SAMPLE)

ICGV 91323

GOOD 1289 6 165 21 MECHANICALLY

DAMAGED

6 5 4 1

TERMITE SCARIFIED 14 1 2 1 IMMATURE 40 1 38 5 ROTTEN 8 1 3 21

ICGV 91324

GOOD 1198 1 101 26 MECHANICALLY

DAMAGED

12 3 3 1

TERMITE SCARIFIED 16 0 4 1 IMMATURE 40 0 45 7 ROTTEN 14 0 5 51

GOOD 1355 7 213 11

ICGV 91328

MECHANICALLY

DAMAGED

9 1 0 0

TERMITE SCARIFIED 7 0 0 4 IMMATURE 31 1 29 0 ROTTEN 16 1 5 17

Table 1b: Continued

CONDITION OF THE GROUNDNUT SEED

GROUNDNUT

GENOTYPES CONDITION OF THE

GROUNDNUT PODS GOOD

(NO. PER

SAMPLE)

BROKEN (NO. PER

SAMPLE) SHRIVELLED (NO. PER

SAMPLE) ROTTEN

(NO. PER

SAMPLE)

ICGV 91334

GOOD 2053 3 227 25 MECHANICALLY

DAMAGED

9 1 3 1

TERMITE SCARIFIED 46 0 3 9 IMMATURE 46 1 39 2 ROTTEN 36 2 7 138

J 11

GOOD 1893 4 296 18 MECHANICALLY

DAMAGED

18 5 10 1

TERMITE SCARIFIED 26 1 2 3 IMMATURE 20 0 31 2 ROTTEN 23 0 5 51

JL 24

GOOD 1528 4 196 26 MECHANICALLY

DAMAGED

1 2 1 0

TERMITE SCARIFIED 38 0 3 11 IMMATURE 32 0 40 5 ROTTEN 30 1 5 49

Table 1b: Contunued

CONDITION OF THE GROUNDNUT SEED

GROUNDNUT

GENOTYPES CONDITION OF THE

GROUNDNUT PODS GOOD

(NO. PER

SAMPLE)

BROKEN (NO. PER

SAMPLE) SHRIVELLED (NO. PER

SAMPLE) ROTTEN

(NO. PER

SAMPLE)

GOOD 1196 0 104 3

UF 71513-1

MECHANICALLY

DAMAGED

854 1 105 20

TERMITE SCARIFIED 37 0 2 3 IMMATURE 50 0 75 5 ROTTEN 44 1 3 109

ICGV 91329

GOOD 1308 3 281 15 MECHANICALLY

DAMAGED

18 9 9 0

TERMITE SCARIFIED 17 0 0 5 IMMATURE 51 0 43 7 ROTTEN 7 0 0 25

MALIMBA

GOOD 1297 2 207 14 MECHANICALLY

DAMAGED

5 0 2 1

TERMITE SCARIFIED 20 1 4 1 IMMATURE 18 0 47 4 ROTTEN 8 0 3 13

Table 1b: Continued

CONDITION OF THE GROUNDNUT SEED

GROUNDNUT

GENOTYPES CONDITION OF THE

GROUNDNUT PODS GOOD

(NO. PER

SAMPLE)

BROKEN (NO. PER

SAMPLE) SHRIVELLED (NO. PER

SAMPLE) ROTTEN

(NO. PER

SAMPLE)

BEBIANO BRANCO

GOOD 1469 4 201 24 MECHANICALLY

DAMAGED

5 2 4 0

TERMITE SCARIFIED 6 0 1 6 IMMATURE 46 1 47 2 ROTTEN 11 1 5 11

ICGMS # 5

GOOD 1004 2 99 14 MECHANICALLY

DAMAGED

2 1 1 0

TERMITE SCARIFIED 2 0 1 1 IMMATURE 17 0 21 3 ROTTEN 9 0 8 28

SELLIE

GOOD 1204 1 116 13 MECHANICALLY

DAMAGED

6 2 0 0

TERMITE SCARIFIED 10 0 2 1 IMMATURE 68 0 87 8 ROTTEN 16 1 4 21

Table 1b: Continued

CONDITION OF THE GROUNDNUT SEED

GROUNDNUT

GENOTYPES CONDITION OF THE

GROUNDNUT PODS GOOD

(NO. PER

SAMPLE)

BROKEN

(NO. PER

SAMPLE)

SHRIVELLED (NO. PER

SAMPLE) ROTTEN (NO. PER

SAMPLE)

C G 7

GOOD 1249 5 96 20 MECHANICALLY

DAMAGED

31 8 4 4

TERMITE SCARIFIED 8 0 0 1 IMMATURE 46 2 39 7 ROTTEN 11 0 0 32

NATAL COMMON

GOOD 1117 2 246 15 MECHANICALLY

DAMAGED

6 3 4 0

TERMITE SCARIFIED 16 0 5 1 IMMATURE 34 1 48 2 ROTTEN 22 1 2 24

COMET

GOOD 1207 2 181 4 MECHANICALLY

DAMAGED

4 2 2 0

TERMITE SCARIFIED 24 0 5 3 IMMATURE 39 0 50 1 ROTTEN 24 0 6 42

Table 1b: Continued

CONDITION OF THE GROUNDNUT SEED

GROUNDNUT

GENOTYPES CONDITION OF THE

GROUNDNUT PODS GOOD

(NO. PER

SAMPLE)

BROKEN (NO. PER

SAMPLE) SHRIVELLED (NO. PER

SAMPLE) ROTTEN (NO.PER

SAMPLE)

SWALLOW

GOOD 1114 4 123 38 MECHANICALLY

DAMAGED

17 4 2 2

TERMITE SCARIFIED 13 0 2 1 IMMATURE 40 0 34 8 ROTTEN 13 3 5 55

TRIAL MEANS GOOD 1387 3 187 15 MECHANICALLY

DAMAGED

43 3 7 2

TERMITE SCARIFIED 19 0 2 3 IMMATURE 43 0 43 5 ROTTEN 18 1 6 40

GROUNDNUT 57.5 0.7 13.1 5.7

GENOTYPES (A) S. E + CONDITION OF THE PODS (B) 25.7 0.3 5.8 2.5

A X B 128.5 1.5 29.2 12.7 C.V. (%) 73.72 184.99 103.58 171.42

SIGNIFICA-NCE OF THE MEANS GROUNDNUT GENOTYPES (A) NS NS NS *

CONDITION OF THE PODS (B) *** *** *** ***

A X B NS NS NS NS

TABLE 1C: PERCENT SEED MOISTURE CONTENT, PERCENT ISOLATIONS OF THE Aspergillus flavus GROUP OF FUNGI, TOTAL

AFLATOXIN B1 CONTENT AND ISOLATIONS OF OTHER RESIDENT MICROORGANISMS FROM SEED SAMPLES FROM

GROUNDNUT AFLATOXIN FIELD TRIAL CONDUCTED AT CHITEDZE IN THE 1997/98 CROP

GROWING SEASON GROUNDNUT

GENOTYPES % SEED

MOISTURE

CONTENT

% ISOLATIONS OF

THE Aspergillus flavus

GROUP OF

FUNGI

TOTAL

AFLATOXIN B1

CONTENT IN

ng.g-1

LEVEL OF TOTAL

AFLATOXIN B1

CONTENT

ISOLATIONS OF OTHER

RESIDENT SEED

MICROORGANISMS

ICGV 89104 5.2 44 1.0 LOW 1). Fusarium spp

2). Aspergillus niger

3). Penicillium spp.

4). Trichoderma sp.

5). Rhizopus stolonifer ICGV 91278 4.2 52 1.0 LOW - DO - ICGV 91284 3.1 69 2.7 LOW - D0 - ICGV 91289 4.1 69 0.7 LOW - DO - ICGV 91290 3.8 58 2.0 LOW - DO - ICGV 91298 4.0 28 1.0 LOW - D O- ICGV 91305 4.4 41 0.7 LOW - DO- ICGV 91317 5.2 45 1.7 LOW - DO - Table 1c: Continued

GROUNDNUT

GENOTYPES % SEED

MOISTURE

CONTENT

% ISOLATIONS OF

THE Aspergillus flavus

GROUP OF

FUNGI

TOTAL

AFLATOXIN B1

CONTENT

IN ng.g-1

LEVEL OF TOTAL

AFLATOXIN B1

CONTENT

ISOLATIONS OF OTHER

RESIDENT SEED

MICROORGANISMS

ICGV 91322 4.8 37 2.2 LOW 1). Fusarium spp

2). Aspergillus niger

3). Penicillium spp.

4). Trichoderma sp.

5). Rhizopus stolonifer ICGV 91323 3.9 35 0.7 LOW - DO -

ICGV 91324 4.7 23 2.0 LOW - D0 - ICGV 91328 6.2 49 1.0 LOW - DO - ICGV 91334 4.2 27 1.2 LOW - DO - J 11 3.9 75 2.0 LOW - D O- JL 24 4.6 42 1.7 LOW - DO- UF 71513 - 1 6.0 61 1.3 LOW - DO -

Table 1c: Continued

GROUNDNUT

GENOTYPES % SEED

MOISTURE

CONTENT

% ISOLATIONS OF THE

Aspergillus flavus GROUP

OF

FUNGI

TOTAL

AFLATOXIN

B1 CONTENT

IN

ng.g-1

LEVEL OF TOTAL

AFLATOXIN

B1 CONTENT

ISOLATIONS OF OTHER

RESIDENT SEED

MICROORGANISMS

ICGV 91329 4.0 27 1.2 LOW 1). Fusarium spp

2). Aspergillus niger

3). Penicillium spp.

4). Trichoderma sp.

5). Rhizopus stolonifer MALIMBA 4.0 49 2.0 LOW - DO - BEBIANO

BRANCO 6.2 24 2.0 LOW - D0 -

ICGMS # 5 4.0 29 1.5 LOW - DO - SELLIE 4.7 18 1.2 LOW - DO - CG 7 4.1 85 0.7 LOW - D O- NATAL COMMON 5.8 49 0.8 LOW - DO- COMET 4.4 31 1.0 LOW - DO -

Table 1c: Continued

GROUNDNUT

GENOTYPES % SEED

MOISTURE % ISOLATIONS OF THE

Aspergillus flavus GROUP

TOTAL

AFLATOXIN B1

LEVEL OF

TOTAL

ISOLATIONS OF OTHER

RESIDENT SEED

CONTENT

OF FUNGI CONTENT

IN ng.g-1

AFLATOXIN B1

CONTENT

MICROORGANISMS

SWALLOW 4.5 35 1.7 LOW 1). Fusarium spp

2). Aspergillus niger

3). Penicillium spp.

4). Trichoderma sp.

5). Rhizopus stolonifer TRIAL MEANS

S.E. +

C.V. (%)

SIGNIFICANCE OF

TRIAL MEANS

4.6

0.68

25.85

NS

44

13.3

52.35

*

1.4

0.06

75.27

NS

LOW

TABLE 2a: PLANT STAND COUNTS AT EMERGENCE AND AT HARVEST, MEAN EARLY AND LATE LEAF SPOTS AND RUST

SCORES, ROSETTE AND TERMITES DAMAGED PLANT COUNTS RECORDED FROM THE GROUNDNUTAFLATOXIN FIELD TRIAL

CONDUCTED AT CHITALA IN THE 1997/98 CROP GROWING SEASON

GROUNDNUT

GENOTYPES STAND COUNT AT

EMERGENCE

(PLANTS PER HA.

IN '000)

STAND COUNT

AT HARVEST

(PLANTS PER

HA. IN '000)

MEAN

EARLY

LEAF SPOT

SCORES (1-

9)

MEAN

LATE LEAF

SPOT

SCORES (1-

9)

MEAN

RUST

SCORES

(1-9)

ROSETTE

DAMAGED

PLANT COUNTS

(PLANTS PER

HA.)

TERMITES

DAMAGED

PLANT COUNTS

(PLANTS PER HA.

IN '000) CG 7 102 94 5 3 4 139 7 ICGV 91278 106 100 7 6 3 0 10 ICGV 91305 103 96 5 4 2 139 10 ICGV 91322 105 96 6 5 3 417 10 ICGV 91323 103 95 6 4 2 0 10 RG 1 105 100 4 3 2 0 9 J 11 108 97 6 6 3 0 10 UF 71513-1 104 94 7 6 4 0 10 MALIMBA 99 88 7 6 3 0 10 JL 24 97 89 7 6 5 0 9

Table 2a: Continued

GROUNDNUT

GENOTYPES STAND COUNT AT

EMERGENCE

(PLANTS PER HA.

STAND COUNT

AT HARVEST

(PLANTS PER

MEAN

EARLY

LEAF SPOT

MEAN

LATE LEAF

SPOT

MEAN

RUST

SCORES

ROSETTE

DAMAGED

PLANT COUNTS

TERMITES

DAMAGED

PLANT COUNTS

IN '000) HA. IN '000) SCORES (1-

9) SCORES (1-

9) (1-9) (PLANTS PER

HA.) (PLANTS PER HA.

IN '000) TRIAL MEANS 103 95 5.9 4.8 3.1 69 10 S.E. + 2.9 2.8 0.3 0.3 0.4 148.2 0.2 C.V. (%) 6.30 6.58 11.65 13.19 29.50 477.26 5.60 SIGNIFI-

CANCE OF TREATMENT

MEANS

NS * *** *** *** NS ***

TABLE 2b: RECORD OF COUNTS OF GOOD, BROKEN, SHRIVELLED AND ROTTEN SEED FROM THE GOOD, DAMAGED,

TERMITES SCARIFIED, IMMATURE AND ROTTEN PODS FROM THE GROUNDNUT AFLATOXIN FIELD TRIALCONDUCTED AT

CHITALA IN THE 1997/98 CROP GROWING SEASON

CONDITION OF THE GROUNDNUT SEED

GROUNDNUT

GENOTYPES CONDITION OF THE

GROUNDNUT PODS GOOD (NO. PER

SAMPLE) BROKEN (NO.

PER SAMPLE) SHRIVELLED

(NO.PER SAMPLE) ROTTEN (NO.

PER SAMPLE)

CG 7

GOOD 1431 22 132 39 MECHANICALLY DAMAGED 7 3 0 3 TERMITES SCARIFIED 27 0 12 6 IMMATURE 39 2 32 6 ROTTEN 17 0 21 40

GOOD 1424 11 103 37 MECHANICALLY DAMAGED 24 6 6 3 TERMITES SCARIFIED 34 1 12 3

ICGV 91278 IMMATURE 51 1 28 4 ROTTEN 12 2 9 21

Table 2b: Continued

CONDITION OF THE GROUNDNUT SEED

GROUNDNUT

GENOTYPES CONDITION OF THE

GROUNDNUT PODS GOOD (NO. PER

SAMPLE) BROKEN (NO.

PER SAMPLE) SHRIVELLED

(NO.PER SAMPLE) ROTTEN (NO.

PER SAMPLE)

ICGV 91305

GOOD 1561 17 139 39 MECHANICALLY DAMAGED 6 3 4 0 TERMITES SCARIFIED 26 0 9 3 IMMATURE 30 1 9 4 ROTTEN 6 0 4 14

ICGV 91322

GOOD 1375 13 87 30 MECHANICALLY DAMAGED 8 5 1 2 TERMITES SCARIFIED 24 1 3 4 IMMATURE 46 0 31 7 ROTTEN 10 2 9 39

Table 2b: Continued

CONDITION OF THE GROUNDNUT SEED

GROUNDNUT

GENOTYPES CONDITION OF THE

GROUNDNUT PODS GOOD (NO. PER

SAMPLE) BROKEN (NO.

PER SAMPLE) SHRIVELLED

(NO.PER SAMPLE) ROTTEN (NO.

PER SAMPLE)

ICGV 91323

GOOD 1255 32 117 19 MECHANICALLY DAMAGED 16 11 2 1 TERMITES SCARIFIED 26 0 12 6 IMMATURE 44 4 22 4 ROTTEN 8 0 3 14

R G 1

GOOD 3213 6 89 32 MECHANICALLY DAMAGED 21 6 3 1 TERMITES SCARIFIED 28 0 1 3 IMMATURE 56 1 29 11

ROTTEN 19 1 5 32

Table 2b: Continued

CONDITION OF THE GROUNDNUT SEED

GROUNDNUT

GENOTYPES CONDITION OF THE

GROUNDNUT PODS GOOD (NO. PER

SAMPLE) BROKEN (NO.

PER SAMPLE) SHRIVELLED

(NO.PER SAMPLE) ROTTEN (NO.

PER SAMPLE)

J 11

GOOD 1354 16 102 38 MECHANICALLY DAMAGED 7 4 1 1 TERMITES SCARIFIED 12 0 8 0 IMMATURE 37 2 22 5 ROTTEN 9 1 9 38

U F 71513 - 1

GOOD 1191 12 94 27 MECHANICALLY DAMAGED 20 9 2 2 TERMITES SCARIFIED 53 1 6 6 IMMATURE 47 1 34 7 ROTTEN 11 1 4 25

Table 2b: Continued

CONDITION OF THE GROUNDNUT SEED

GROUNDNUT

GENOTYPES CONDITION OF THE

GROUNDNUT PODS GOOD (NO. PER

SAMPLE) BROKEN (NO.

PER SAMPLE) SHRIVELLED

(NO.PER SAMPLE) ROTTEN (NO.

PER SAMPLE)

GOOD 1236 14 98 40 MECHANICALLY

DAMAGED 22 5 4 1

MALIMBA

TERMITES SCARIFIED 51 2 3 9 IMMATURE 86 5 55 13 ROTTEN 14 2 7 16

J L 24

GOOD 1301 7 114 34 MECHANICALLY

DAMAGED 30 8 6 4

TERMITES SCARIFIED 59 0 12 7 IMMATURE 57 0 38 12 ROTTEN 12 1 9 26

Table 2b: Continued

CONDITION OF THE GROUNDNUT SEED

GROUNDNUT GENOTYPES CONDITION OF THE

GROUNDNUT PODS GOOD (NO.

PER SAMPLE) BROKEN (NO.

PER SAMPLE) SHRIVELLED

(NO.PER SAMPLE) ROTTEN (NO.

PER SAMPLE)

TRIAL MEANS

GOOD 1534 15 107 34 MECHANICALLY

DAMAGED 16 6 3 2

TERMITES SCARIFIED 34 1 8 5 IMMATURE 49 2 30 7 ROTTEN 12 1 8 26

S. E. + GROUNDNUT GENOTYPES

(A) 113.0 1.4 4.7 3.5

CONDITION OF THE PODS

(B) 79.9 1.0 3.3 2.5

A X B 252.8 3.1 10.5 7.8 C.V. (%) 171.76 141.13 75.05 117.65

SIGNIFICA-NCE

OF THE MEANS

GROUNDNUT GENOTYPES

(A) NS NS NS NS

CONDITION OF THE

GROUNDNUT PODS (B) *** *** *** ***

A X B NS NS NS

TABLE 2C: PERCENT SEED MOISTURE CONTENT, PERCENT ISOLATIONS OF THE Aspergillus flavus GROUP OF FUNGI, TOTAL

AFLATOXIN B1 CONTENT AND ISOLATIONS OF OTHER RESIDENT MICRO-ORGANISMS FROM SEED FROM THE GROUNDNUT

AFLATOXIN FIELD TRIAL CONDUCTED AT CHITALA IN THE 1997/98 CROP GROWING

SEASON GROUNDNUT

GENOTYPES % SEED

MOISTURE

CONTENT

% ISOLATIONS OF

Aspergillus flavus

GROUP OF FUNGI

TOTAL

AFLATOXIN B1

CONTENT

IN ng.g-1

LEVEL OF TOTAL

AFLATOXIN B1

CONTENT

ISOLATIONS OF OTHER

RESIDENT SEED

MICROORGANISMS

C G 7 3.6 53 0.5 LOW 1) Aspergillus niger

2) Fusarium spp.

3) Penicillium spp.

4) Trichoderma sp. ICGV 91278 3.2 63 2.0 LOW 1) Aspergillus niger

2) Penicillium spp.

3) Fusarium spp.

4) Trichoderma sp. ICGV 91305 3.1 31 1.6 LOW 1) Aspergillus niger

2) Fusarium spp.

3) Penicillium spp.

4) Trichoderma sp.

Table 2C: Continued

GROUNDNUT

GENOTYPES % SEED

MOISTURE

CONTENT

% ISOLATIONS OF

Aspergillus flavus

GROUP OF FUNGI

TOTAL

AFLATOXIN B1

CONTENT

IN ng.g-1

LEVEL OF TOTAL

AFLATOXIN B1

CONTENT

ISOLATIONS OF OTHER

RESIDENT SEED

MICROORGANISMS

ICGV 91322 3.4 37 2.0 LOW 1) Aspergillus niger

2) Fusarium spp.

3) Trichoderma sp.

4) Penicillium spp. ICGV 91323 3.0 67 2.0 LOW 1) Aspergillus niger

2) Fusarium spp

3) Penicillium spp.

4) Trichoderma sp. R G 1 3.6 56 2.5 LOW 1) Aspergillus niger

2) Penicillium spp.

3) Fusarium spp.

4) Trichoderma sp.

J 11 3.1 24 2.0 LOW 1) Aspergillus niger

2) Penicillium spp.

3) Fusarium spp.

4) Trichoderma sp.

Table 2C: Continued

GROUNDNUT

GENOTYPES % SEED

MOISTURE

CONTENT

% ISOLATIONS OF

Aspergillus flavus

GROUP OF FUNGI

TOTAL

AFLATOXIN B1,

CONTENT

IN ng.g-1

LEVEL OF TOTAL

AFLATOXIN IN B1

CONTENT

ISOLATIONS OF OTHER

RESIDENT SEED

MICROORGANISMS

UF 71513 - 1 3.2 64 3.0 LOW 1) Aspergillus niger

2) Fusarium spp.

3) Penicillium spp.

4) Trichoderma sp. MALIMBA 3.1 46 3.0 LOW 1) Aspergillus niger

2) Penicillium spp.

3) Fusarium spp

4) Trichoderma sp. J L 24 3.2 45 2.5 LOW 1) Aspergillus niger

2) Fusarium spp.

3) Penicillium spp.

4) Trichoderma sp.

TRIAL MEANS

S.E. +

C.V. (%)

SIGNIFICANCE

OF TREATEMENT MEAMS (GENOTYPES)

3.2

0.26

18.22

NS

49

9.9

45.79

*

2.1

0.68

71.71

NS

LOW

TABLE 3a: PLANT STAND COUNTS AT EMERGENCE AND AT HARVEST, MEAN EARLY LEAF SPOT, RUST AND DEFOLIATION

SCORES, COUNTS OF ROSETTE, TERMITES AND PLANT HOPPER DAMAGED PLANTS RECORDED FROM THE GROUNDNUT

AFLATOXIN FIELD TRIAL CONDUCTED AT MAKOKA IN THE 1997/98 CROP GROWING SEASON

GROUNDNUT

GENOTYPES STAND COUNT

AT

STAND

COUNT AT

MEAN

EARLY

MEAN

RUST

MEAN

DEFOLIATION

ROSETTE

DAMAGED

TERMITES

DAMAGED

PLANT

EMERGENCE

(PLANTS PER

HA. IN '000)

HARVEST

(PLANTS

PER HA. IN

'000)

LEAF

SPOT

SCORES

(1-9)

SCORES

(1-9)

SCORES (1-9) PLANT

COUNTS

(PLANTS PER

HA. IN '000)

PLANT

COUNTS

(PLANTS PER

HA.

IN '000)

HOPPER

DAMAGED

PLANT

COUNTS

(PLANTS PER

HA. IN '000) CG 7 115 110 5 6 6 - 1 3 ICGV 91278 128 126 6 7 6 - 1 5 ICGV 91305 131 121 6 6 6 - 3 3 ICGV 91322 126 126 6 6 5 - 0 2 ICGV 91323 128 128 6 5 6 - 0 2 R G 1 127 127 7 6 6 - 2 3 J 11 126 126 7 6 6 - 0 2 UF 71513-1 135 116 6 6 6 - 0 3 MALIMBA 101 101 6 6 6 - 3 3

Table 3a: Continued

GROUNDNUT

GENOTYPES STAND COUNT

AT

EMERGENCE

(PLANTS PER

HA. IN '000)

STAND

COUNT AT

HARVEST

(PLANTS

PER HA. IN

'000)

MEAN

EARLY

LEAF

SPOT

SCORES

(1-9)

MEAN

RUST

SCORES

(1-9)

MEAN

DEFOLIATION

SCORES (1-9)

ROSETTE

DAMAGED

PLANT

COUNTS

(PLANTS PER

HA. IN '000)

TERMITES

DAMAGED

PLANT

COUNTS

(PLANTS PER

HA.

IN '000)

PLANT

HOPPER

DAMAGED

PLANT

COUNTS

(PLANTS PER

HA. IN '000) J L 24 125 125 6 5 5 - 1 3 TRIAL MEANS 124 124 6 6 6 - 1 3 S.E. + 5.7 4.9 0.3 0.5 0.4 - 1.0 1.0 C.V. (%) 9.11 7.87 8.54 18.50 14.00 - 0.16 0.07 SIGNIFICA-

NCE OF

MEANS

GENOTYPES

*** NS * NS NS - NS NS

TABLE 3b: RECORD OF COUNTS OF THE GOOD, BROKEN, SHRIVELLED, AND ROTTEN SEED FROM THE GOOD, DAMAGED,

TERMITES SCARIFIED, IMMATURE AND ROTTEN PODS FROM THE GROUNDNUT AFLATOXIN

FIELD TRIAL CONDUCTED AT MAKOKA IN THE 1997/98 CROP GROWING SEASON

CONDITION OF THE GROUNDNUT SEED

GROUNDNUT

GENOTYPES CONDITION OF THE

GROUNDNUT PODS GOOD (NO. PER

SAMPLE) BROKEN (NO.

PER SAMPLE) SHRIVELLED

(NO.PER SAMPLE) ROTTEN (NO.

PER SAMPLE)

CG 7

GOOD 1501 5 112 92 MECHANICALLY DAMAGED 21 6 2 5 TERMITES SCARIFIED 74 0 31 30 IMMATURE 93 1 38 32 ROTTEN 7 3 2 17

ICGV 91278

GOOD 1597 7 118 84 MECHANICALLY DAMAGED 6 3 2 2 TERMITES SCARIFIED 56 1 3 20 IMMATURE 59 2 32 20 ROTTEN 20 1 2 41

Table 3b: Continued

CONDITION OF THE GROUNDNUT SEED

GROUNDNUT

GENOTYPES CONDITION OF THE

GROUNDNUT PODS GOOD (NO. PER

SAMPLE) BROKEN (NO.

PER SAMPLE) SHRIVELLED

(NO.PER SAMPLE) ROTTEN (NO.

PER SAMPLE)

ICGV 91305

GOOD 1454 5 117 36 MECHANICALLY DAMAGED 47 5 13 6 TERMITES SCARIFIED 111 0 65 16 IMMATURE 76 3 18 29 ROTTEN 18 1 2 35

ICGV 91322

GOOD 1417 5 120 70 MECHANICALLY DAMAGED 17 5 8 2 TERMITES SCARIFIED 31 0 18 24 IMMATURE 28 1 30 10 ROTTEN 23 3 21 15

Table 3b: Continued

CONDITION OF THE GROUNDNUT SEED

GROUNDNUT

GENOTYPES CONDITION OF THE

GROUNDNUT PODS GOOD (NO. PER

SAMPLE) BROKEN (NO.

PER SAMPLE) SHRIVELLED

(NO.PER SAMPLE) ROTTEN (NO.

PER SAMPLE)

ICGV 91323

GOOD 1349 7 176 82 MECHANICALLY DAMAGED 31 4 3 4 TERMITES SCARIFIED 22 1 9 8 IMMATURE 30 0 22 28 ROTTEN 13 0 6 13

R G 1

GOOD 1577 3 142 49 MECHANICALLY DAMAGED 25 3 7 15 TERMITES SCARIFIED 19 1 8 20 IMMATURE 189 4 102 11 ROTTEN 31 2 3 23

Table 3b: Continued

CONDITION OF THE GROUNDNUT SEED

GROUNDNUT

GENOTYPES CONDITION OF THE

GROUNDNUT PODS GOOD (NO. PER

SAMPLE) BROKEN (NO.

PER SAMPLE) SHRIVELLED

(NO.PER SAMPLE) ROTTEN (NO.

PER SAMPLE)

J 11

GOOD 1296 3 45 51 MECHANICALLY DAMAGED 158 3 13 7 TERMITES SCARIFIED 47 1 29 18 IMMATURE 255 0 117 31 ROTTEN 74 0 28 52

U F 71513 - 1

GOOD 1345 5 125 71 MECHANICALLY DAMAGED 20 4 9 5 TERMITES SCARIFIED 71 0 11 14 IMMATURE 227 1 40 16 ROTTEN 11 1 5 23

Table 3b: Continued

CONDITION OF THE GROUNDNUT SEED

GROUNDNUT

GENOTYPES CONDITION OF THE

GROUNDNUT PODS GOOD (NO. PER

SAMPLE) BROKEN (NO.

PER SAMPLE) SHRIVELLED

(NO.PER SAMPLE) ROTTEN (NO.

PER SAMPLE)

MALIMBA

GOOD 1569 1 177 73 MECHANICALLY

DAMAGED 25 4 9 4

TERMITES SCARIFIED 45 1 21 73 IMMATURE 129 3 63 23 ROTTEN 24 1 13 39

J L 24

GOOD 1412 8 99 76 MECHANICALLY

DAMAGED 29 4 8 4

TERMITES SCARIFIED 32 1 18 18 IMMATURE 82 0 41 15 ROTTEN 18 0 5 28

Table 3b: Continued

CONDITION OF THE GROUNDNUT SEED

GROUNDNUT GENOTYPES CONDITION OF THE

GROUNDNUT PODS GOOD (NO.

PER SAMPLE) BROKEN (NO.

PER SAMPLE) SHRIVELLED

(NO.PER SAMPLE) ROTTEN (NO.

PER SAMPLE)

TRIAL MEANS

GOOD 1451 5 123 68 MECHANICALLY

DAMAGED 38 4 7 5

TERMITES SCARIFIED 51 1 21 24 IMMATURE 117 1 50 21 ROTTEN 24 1 9 28

S. E. + GROUNDNUT

GENOTYPES (A) 62.1 0.7 9.9 5.4

CONDITION OF THE

PODS (B) 43.9 0.5 7.0 3.8

A X B 138.9 1.5 22.0 12.2 C.V. (%) 82.68 131.14 104.65 82.70

SIGNIFICA-NCES OF

THE TREAT-MENT

GROUNDNUT

GENOTYPES (A) NS NS NS NS

CONDITION OF THE *** *** *** ***

MEANS GROUNDNUT PODS (B) A X B NS NS NS NS

TABLE 3C: PERCENT SEED MOISTURE CONTENT, PERCENT ISOLATIONS OF THE Aspergillus flavus GROUP OF FUNGI, TOTAL

AFLATOXIN B1 CONTENT AND RECORD OF ISOLATIONS OF OTHER RESIDENT MICRO-ORGANISMS FROM SEED FROM THE

GROUNDNUT AFLATOXIN FIELD TRIAL CONDUCTED AT MAKOKA IN THE 1997/98 CROP GROWING

SEASON GROUNDNUT

GENOTYPES % SEED

MOISTURE

CONTENT

% ISOLATIONS OF

Aspergillus flavus

GROUP OF FUNGI

TOTAL

AFLATOXIN B1

CONTENT IN ng.g-1

LEVEL OF TOTAL

AFLATOXIN B1

CONTENT

ISOLATIONS OF OTHER

RESIDENT SEED

MICROORGANISMS C G 7 4.9 40 1.5 LOW 1) Aspergillus niger

2) Penicillium spp

3) Fusarium spp.

4) Trichoderma sp. ICGV 91278 4.7 22 1.5 LOW 1) Aspergillus niger

2) Trichoderma sp.

3) Fusarium spp

4) Penicillium spp. ICGV 91305 6.2 19 1.9 LOW 1) Aspergillus niger

2) Fusarium spp.

3) Trichoderma sp.

4) Penicillium spp.

Table 3C: Continued

GROUNDNUT

GENOTYPES % SEED

MOISTURE

CONTENT

% ISOLATIONS OF

Aspergillus flavus

GROUP OF FUNGI

TOTAL

AFLATOXIN B1

CONTENT IN ng.g-1

LEVEL OF TOTAL

AFLATOXIN B1

CONTENT

ISOLATIONS OF OTHER

RESIDENT SEED

MICROORGANISMS ICGV 91322 4.3 22 0 LOW 1) Trichoderma sp.

2) Fusarium spp.

3) Aspergillus niger

4) Penicillium spp. ICGV 91323 4.7 19 2.5 LOW 1) Aspergillus niger

2) Trichoderma sp.

3) Penicillium spp.

4) Fusarium spp R G 1 5.9 22 2.5 LOW 1) Aspergillus niger

2) Trichoderma sp.

3) Penicillium spp.

3) Fusarium spp.

J 11 4.7 18 0.9 LOW 1) Aspergillus niger

2) Fusarium spp.

3) Penicillium spp.

4) Trichoderma sp.

Table 3C: Continued

GROUNDNUT

GENOTYPES % SEED

MOISTURE

CONTENT

% ISOLATIONS OF

Aspergillus flavus

GROUP OF FUNGI

TOTAL

AFLATOXIN B1,

CONTENT IN ng.g-1

LEVEL OF TOTAL

AFLATOXIN B1

CONTENT

ISOLATIONS OF OTHER

RESIDENT SEED

MICROORGANISMS UF 71513 - 1 4.5 16 0 LOW 1) Aspergillus niger

2) Penicillium spp.

2) Trichoderma sp.

4) Fusarium spp. MALIMBA 4.4 24 1.5 LOW 1) Aspergillus niger

2) Trichoderma sp.

3) Penicillium spp.

4) Fusarium spp. J L 24 5.8 20 0.9 LOW 1) Aspergillus niger

2) Fusarium spp.

3) Penicillium spp.

4) Trichoderma sp.

TRIAL MEANS

S.E. +

C.V. (%)

SIGNIFICANCES

OF THE TREATEMENT (GENOTYPES) MEANS

5.0

0.68

27.02

NS

22

6.8

61.85

NS

1.3

0.75

114.04

NS

LOW

AFLATOXIN RESEARCH PROJECT ON GROUNDNUTS IN MALAWI