19

SECTION I

PREVALENCE

AND

COMMUNITY ANALYSIS

20

INTRODUCTION

Among the plant parasitic nematodes, root-knot nematodes (Meloidogyne spp.) are

distributed worldwide and possess a broad host range of economically important crops.They are

recognized as causing more economic damage to food crops compared from any other plant

parasitic nematode and are ranked first among ten highly pathogenic nematode genera. About

2000 plants are susceptible to their infection causing approximately 5% of global crop loss

(Hussey and Janssen, 2002). Generally, root-knot nematodes inhabit farm soils with the species

of host plants cultivated influencing their distribution. The population of nematodes is mostly

found 5 to 30 cm beneath the soil surface. In presence of a suitable host the distribution of

Meloidogyne in the soil reaches the same as that of crop plant roots.

Damage due to the root-knot nematode causes poor growth, decline in the quality and

yield of the crop and reduction in the resistance to stressors, such as, drought, diseases, etc.

Damaged roots fail to utilize water and fertilizers effectively, leading to additional losses. A high

level of root-knot nematode damage can lead to total crop loss. Infections of young plants are

lethal, while those in mature plants are responsible for yield reduction. Besides affecting plant

health, they also act as vectors of other pathogens (bacteria, fungus, virus), wounding agents,

host modifiers, resistance breakers and rhizosphere modifiers.

To meet the increasing demands of the ever growing human population, an effective use

of available land for increasing production of food and fibre throughout the world has become a

necessity. Besides, expensive labor and higher cost of inputs in agriculture are major constraints.

Hence, it becomes imperative to control losses due to diseases and pests like nematodes in

agriculture production. The basic requirement would be thus to find out the economic importance

21

of the parasites on the basis of population densities and distribution, nature and amount of

damage and the losses in yield.

REVIEW OF LITERATURE

India is a major producer of pulses in the world accounting 25% of the global

output. A number of plant parasitic nematodes have been reported on pulses causing potential

yield losses. Ali et al. (2006) studied the community analysis of plant parasitic nematodes

associated with the rhizosphere of pulse crops viz., pigeon pea, chickpea, lentil and field pea in

Hamirpur district, Uttar Pradesh. Analysis of soil samples of chickpea revealed the presence of

Hoplolaimus indicus, with highest frequency, density, prominence value and importance value

followed by Tylenchorhynchus mashhoodi. Soil samples of lentil showed presence of five

species of nematodes of which T. mashhoodi had highest absolute frequency, density and

prominence value, while, H. indicus had highest biomass and importance value. Nine plant

parasitic nematodes were found associated with pigeon pea with T. mashhoodi most frequent and

abundant species and Xiphinema americanum had the maximum biomass. Seven species of plant

parasitic nematodes were associated with field pea. Among them T. mashhoodi had highest

frequency, density, prominence value and importance value, followed by Filenchus sp.

Maize (Zea mays L.) is one of the most important kharif cereal crops of the world.

Infection of root-knot nematode, Meloidogyne incognita showing stunting and yellowing

symptoms on the above ground plant parts and numerous small to very big size gall/knots has

been reported on maize crops in Jammu (Singh et al., 2007). Aphelenchoides besseyi was

observed to possess very high densities in rice belonging to 14 districts of West Bengal (Das and

22

Khan, 2007). Meloidogyne graminicola were found associated with rice (Oryza sativa) in Jammu

(Singh et al., 2007).

A survey was undertaken by Sudheer et al. (2007) in major pomegranate growing areas

in Anantpur district of Andhra Pradesh during kharif 2006 to assess the nematode problems.

Most of the pomegranate orchards were found infested with the root-knot nematode,

Meloidogyne incognita. The intensity of root-knot nematode damage increased with increase in

the age of the plant. Besides, analysis of community structure (Sudheer et al., 2008) revealed

that Meloidogyne incognita was major problem associated with tomato, pomegranate, banana,

chilli, muskmelon, brinjal, mulberry and gourds in Anantpur and Chittoor. Rotylenchulus

reniformis was predominant in Guntur and Mahaboobnagar districts, associated with turmeric,

castor, red gram and cotton. Helicotylenchus spp. was major in Kadappa, Kurnool, Nalgonda and

Prakasam districts associated with sunflower, banana, chilli, sugarcane, cotton and tomato. M.

graminicola was found only in Nellore district.

Saha et al. (2006) conducted a survey for nematode fauna associated with Litchi (Litchi

chinensis) at Company Bagh in Muzaffarnagar District of Uttar Pradesh. They observed that

among all the nematode species, Rotylenchulus reniformis was found to be the most important

phytoparasitic nematode with the highest prominence value (42.51), followed by the

Tylenchorhynchus brevilineatus with relative prominence value of 17.90. Plant parasitic

nematodes affecting litchi plants in North Tripura district are reported to include Rotylenchulus

reniformis, Helicotylenchus indicus, Tylenchorhynchus leviterminalis and Xiphinema spp. along

with Hemicriconemoides litchi, Meloidogyne incognita, Helicotylenchus dihystera, Hoplolaimus

indicus and Xiphinema brevicolle (Nath et al., 2008). On the other hand, Helicotylenchus spp.

were found predominant in Pineapple crops of Meghalaya ,followed by Meloidogyne incognita

23

and species of Tylenchorhynchus, Rotylenchulus reniformis, Paralongidorus, Tylenchus,

Ditylenchus, Aphelenchoides, Criconemoides and Pratylenchus (Devi ,2007).

Gantait et al. (2006) studied the monthly population fluctuation in plant parasitic

nematodes associated with banana plantation in Paschim Medinipur district, West Bengal, India

and its correlation with the temperature, moisture, pH and organic carbon content of the soil.

They observed four genera of plant parasitic nematodes viz. Rotylenchulus reniformis,

Tylenchorhynchus coffeae, Helicotylenchus crenacauda and Hoplolaimus indicus to be

associated with Banana, with all the four species reaching peak in August, and declining till

January. A second but smaller peak was observed in March, followed by decline till June,

showing a bimodal population fluctuation in all the cases. Temperature, moisture and organic

carbon content showed positive correlation with the population whereas a negative correlation

existed in response to pH.

An extensive survey by Sundraraju (2006) revealed the presence of 13 genera of plant

parasitic nematodes in Banana in Andhra Pradesh. Root-knot nematode (Meloidogyne incognita)

was most predominant with highest prominence value, followed by root-lesion nematode

(Pratylenchus coffeae) and spiral nematode (Helicotylenchus multicinctus). M. incognita was

also recorded as a predominant species from all the cultivars surveyed, whereas the burrowing

nematode, Radopholus similis was recorded only from cv. Robusta. Cent per cent occurrence of

M. incognita was recorded from alluvial soil followed by sandy loam soil. P. coffeae was also

recorded maximum in alluvial soil followed by sandy loam. Studies on the vertical and

horizontal distribution of Pratylenchus coffeae and other major nematodes in banana (Sundraraju

, 2009) revealed the maximum nematode population at flowering stage followed by harvesting

stage, at a distance of 25 cm and 50 cm from the base of the corm with a depth of 26-50 cm.

24

Negligible population was noticed at a distance of 75 cm from the base of the corm with a depth

of 51-75 cm. The major nematodes observed were Pratylenchus coffeae, Meloidogyne incognita,

Helicotylenchus multicinctus, Rotylenchulus reniformis, Rotylenchulus sp. and Hoplolaimus sp.

In a roving survey of seven districts of West Bengal, Roy et al. (2007) reported the

occurrence of 17 species of plant parasitic nematodes belonging to 8 genera, in leguminous

vegetable crops. In all of the seven districts, root samples showed the presence of root-knot

nematodes in cowpea, Dolichos bean, French bean and pea, but reniform nematodes infected

cowpea and pea only. Based on prominence value, frequency and density, Rotylenchulus

reniformis was observed to be the most prominent followed by species of Meloidogyne,

Tylenchorhynchus, Criconemoides, Pratylenchus, Hoplolaimus, Helicotylenchus and

Hirschmaniella in close association with the crops.

Rotylenchulus reniformis, Helicotylenchus spp., Tylenchorhynchus spp., Meloidogyne

spp. and Pratylenchus spp. were found associated with onion, garlic, wheat, brinjal, castor,

cotton, coconut and flowering plants during a survey of Junagadh district of Gujarat and Diu

Union territory (Patel et al., 2007). Highest frequency of occurrence was recorded in

Helicotylenchus spp. followed by Tylenchorhynchus spp. in Junagadh and in Diu highest

frequency recorded was of Meloidogyne spp. followed by Pratylenchus spp.

Reniform nematodes (Rotylenchulus reniformis) constituted 73.59 % of occurrence in

and around Udaipur. 100 % occurrence was observed in six localities, 90 % in three localities

and 51-90 % in remaining localities. The highest population density was found in Sundervas

(68.60), while low to moderate densities were observed in all the localities on the crops viz.;

mustard, barley, onion and wheat. The highest percent population density of R. reniformis was

observed in castor (67.10 %) with 100 % occurrence. Lesser population densities were found in

25

mustard, barley, onion and wheat. In a few localities ,crops such as, cucumber, bitter gourd and

water melon showed complete absence of reniform nematodes(Lone et al. ,2006).. Out of the 25

cultivated crops surveyed in Udaipur (Lone et al., 2008), reniform nematodes were associated

with all the crops. In some localities, castor, brinjal, tomato, chillies and okra were more

susceptible while, mustard, barley, onion and wheat were low to moderately susceptible. Okra,

cowpea, onion, cucumber, bitter gourd, bottle gourd, pumpkin etc. were found non-susceptible in

few localities.

Community analysis of nematodes in Champawat district of Uttaranchal, India (Rathour

et al., 2006) revealed the presence of several plant parasitic nematodes associated with various

crops. Predominant nematodes were: Meloidogyne spp. (M. incognita and M. javanica)

associated with chilli, okra, papaya and soybean; Quinisulcius acti with maize, chilli, okra and

pumpkin; Rotylenchulus reniformis with castor, papaya and okra; Helicotylenchus spp. (H.

dihystera and H. pseudorobustus) with pumpkin, okra, papaya and soybean; Hemicriconemoides

mangiferae and Pratylenchus curvitatus with mango and litchi; Trichodorus pakistanensis with

litchi, soybean and pumpkin and Hoplolaimus seinhorsti and Tylenchorhynchus indicus were

found to be associated with okra and mango respectively. Presence of M. incognita race 2 was

reported by Naidu et al. (2007) in Chittoor district of Andhra Pradesh, while, heavy infestation

was also observed in Mandya district, Karnataka by Prasad et al. (2006).

Seenivasan and Devrajan (2007) observed eleven plant parasitic nematodes to be

associated with the rhizosphere of Coleus forskohlii. The nematodes encountered most frequently

were Meloidogyne incognita, Hoplolaimus indicus, Xiphinema insigni, Helicotylenchus

multicinctus, Tylenchorhynchus nudus, Pratylenchus coffeae, Tylenchus spp. and Aphelenchus

avenae. In Tamilnadu, M. incognita was observed to be the most predominant nematode species

26

in terms of absolute density, relative density and prominence value followed by Hoplolaimus

indicus.

Nemic population dynamics were studied by Sharma et al. (2007) under Hi-Tech poly

house cultivation of hybrid tomato, sweet pepper and hybrid cucumber under Indo-Israel project

at Indian Agricultural Research Institute, New Delhi. Crop management practices such as

fumigation (formaldehyde @ 250 L/ha) of poly house every year, removal/changing of top soil

and regular supplement of pesticides (carbofuran 3G 1 kg a.i. /ha) were followed regularly.

Despite all these measures, incidence of root-knot nematode (Meloidogyne incognita) problem

was observed in tomato and cucumber. The intensity of infestation and crop damage increased

exponentially even in plots treated with formaldehyde before planting. The rate of growth of

population density and crop damage was much faster in the polyhouse conditions than usually

seen in open fields close by. Soil sampling was done at regular interval which revealed that

sweet pepper was least damaged due to the nematode infestation, while tomato and cucumber

were the most severely affected. About 20 and 45% damage in tomato and cucumber crops

respectively, was observed due to M. incognita.

Studies were undertaken by Kumar et al. (2008) to identify the different species of root-

knot nematodes and races which are prevalent in different agro-climatic regions of the State of

Haryana. Populations of root-knot nematode were observed to belong to three spp. i.e.

Meloidogyne incognita, M. javanica and M. arenaria. Race identification of M. incognita and M.

arenaria revealed the presence of race 2 and 4 of M. incognita, race 2 of M. arenaria and race 1

of M. javanica. Fluctuation of Meloidogyne spp. in different cropping sequences adopted by

farmers of Hissar district of Haryana was studied by Paruthi (2008). Increase in population was

observed to be greater upon sowing susceptible kharif vegetable crops than field crops. Naidu et

27

al. (2007) observed the presence of eight genera of plant parasitic nematodes viz., Meloidogyne

incognita race-2, Helicotylenchus, Tylenchorhynchus brevilineatus, Radopholus similis,

Rotylenchulus reniformis, Pratylenchus, Dorylaimids, Hoplolaimus and Criconemoides in

Chittoor district of Andhra Pradesh. The highest absolute frequency, relative frequency, relative

density and prominence value were recorded for the root-knot nematode.

A survey of bottle gourd (Lagenaria vulgaris) fields was conducted by Singh (2008) for

the occurrence of economically important plant parasitic nematodes in some localities of

Varanasi and Mirzapur districts of Uttar Pradesh. Meloidogyne spp. was most frequently

encountered followed by Hoplolaimus spp., Aphelenchus spp., Helicotylenchus spp., Tylenchus

spp., Longidorus spp., Xiphinema spp., Aphelenchoides spp. and Rotylenchulus spp. Singh and

Satyapriya (2008) reported a new record of root-knot nematode Meloidogyne incognita infecting

bean (Phaseolus vulgaris L.) and pea (Pisum sativum) in Jammu. Chiretta (Swertia chirayita) is

an ayurvedic herb, used as a blood purifier, for skin disease, fever, indigestion and tuberculosis.

Roy et al. (2007), first noticed severe infestation of root-knot nematode Meloidogyne javanica in

Chiretta at Sherpa Gaon village on Lava region (Eastern Himalayan range) of Kalimpong..

A random survey was undertaken by Das and Gaur (2009) to determine the distribution

and abundance of Rotylenchulus reniformis and concomitant nematodes in cotton (Gossypium

spp.) growing areas of Punjab, Haryana and Uttar Pradesh. It was found that reniform nematodes

are wide spread in occurrence in all the three states with absolute frequency 56.5, 30.0 and 42.3

in Punjab, Haryana and Uttar Pradesh respectively. Relative frequency of R. reniformis was 10.2,

21.8 and 16.8 Punjab, Haryana and Uttar Pradesh respectively. In Punjab, the mean population

densities indicated heavier infestation in farmer’s field, compared to less infestation in the

research farm. The predominant plant parasitic nematode species associated with cotton in this

28

region were Meloidogyne incognita, M. javanica, Pratylenchus zeae, P. thornei, Hoplolaimus

indicus, Tylenchorhynchus spp. and Helicotylenchus spp.

Chandel et al. (2002) studied the population behavior of root-knot nematode,

Meloidogyne triticoryzae in the five rice based cropping systems viz., rice-wheat, rice-wheat-

greengram, rice-berseem, rice-potato-greengram and rice-mustard-greengram for a period of two

years. The results revealed that the peak population density occurred in September in the rice

crop. The other crops in the Rabi and summer seasons had a profound influence on the height of

the peak in the succeeding rice crop. Some level of reproduction occurred in wheat, greengram

and berseem in Rabi which contributed to relatively higher equilibrium densities. The potato

variety Pusa Bahar increased the population density while Pusa Badshah decreased it. The lower

temperature during the Rabi season also limited the rate of population growth.

Chandel et al., (2002) studied the effect of puddling and water regimes on hydraulic

conductivity (cm/day) of soil, bulk density (mg/m3) and population density of rice root-knot

nematode, Meloidogyne triticoryzae in experimental rice field. They reported that population

density of M. triticoryzae declined in puddled soil. The invasion of the roots by the second-

generation infective juveniles was reduced. Population density was higher in the non-puddled

soil, especially in unsubmerged condition compared to puddled and submerged soil.

Negi et al., (2009) carried a survey in six districts of Himachal Pradesh, India and

reported twenty one species of nematode parasites belonging to fifteen genera were associated

with rhizosphere of chir pine (Pinus roxburghii Sarg.) nurseries and pine trees (P. wallichiana)

in natural forests. Xiphinema americanum was found to be most predominant followed by X.

insigne, Paratylenchus similis, Hemicriconemoides mangiferae and Varotylus symmetricus with

29

natural pine forest. Tylenchus arcuatus and Malenchus nanellus were recorded as predominant in

nurseries.

Singh (2009 a and b) observed the presence of M. javanica on citrus and M. incognita on

carrot in Jammu. Kalaiarasan et al. (2010) conducted a survey in Anantpur, Chittoor, Kadapa,

Kurnool and Nellore districts of Andhra Pradesh, India and identified Radopholus similis,

Pratylenchus coffeae, Helicotylenchus multicinctus, M. incognita, Tylenchorhynchus spp. and R.

reniformis in banana.

Khan and Ahmad (2000) conducted a survey in Punjab Province of Pakistan and revealed

that out of 1217 samples collected, 498 samples were found to be infested with root-knot

nematodes. They observed that M. incognita was widely distributed species followed by M.

javanica. Anamika et al. (2011) conducted a survey in 21 districts of Uttar Pradesh on crops of

rice, tomato, okra, cowpea, onion, pumpkin, brinjal and bitter gourd to assess the incidence and

intensity of root-knot disease. Attacked plants showed heavy galling, root decay or reduced root

system, yellowish foliage, unthrifty growth and small slow growing fruits and poor yields.

Chandra et al., (2010) and Udo and Ugwuoke, (2010) observed that the degree of damage

done depends upon the pathogenic potential and population growth of nematodes which are

greatly influenced by their initial population densities. Chirchir et al., (2008) reported that the

abundance and distribution of the plant parasitic nematodes in turn are influenced by the soil

texture, crop cycle and anthropogenic factors.

Khan and Anwer (2011) conducted surveys in Aligarh and Hathras districts of Uttar

Pradesh and observed that the Meloidogyne graminicola was found widely distributed in most of

the rice growing localities in all tehsils. Khan et al. (2011) recorded the occurrence of seven

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plant parasitic nematode species associated with some important crops and two weeds Andaman

and Nicobar Islands, India.

Many other works have also documented association of plant parasitic nematodes with

various crops in India and include –Senthil kumar and Rajendran (2005) in Tamilnadu; Joymati

and Mema (2007) in Manipur and Tiwari et al., (2000) and Rathour et al., (2010) in Madhya

Pradesh. Community analysis of plant parasitic nematodes have been studied by Ansari and

Ahmed (2000) in Guava, and Srinivasan et al., (2011) in banana, Thanjavoor, Tamilnadu. Khan

et al., (2010) reported nematode diseases in various crop plants of Chhattisgarh including -

Aphelenchoides besseyii in Rice, R. reniformis in Pulse crops, Meloidogyne spp. and M.incognita

in Vegetable crops and R. similis in Banana.

Review of literature reveals that studies on plant nematodes in India are mostly

restricted to states, such as, Gujarat, Karnataka, Orissa, Tamil nadu, Haryana, Madhya Pradesh ,

Assam, U.P, West Bengal, Himachal Pradesh, Rajasthan, Kerela, Andhra Pradesh and Punjab

(Ali and Koshy,1982; Khan and Khan, 1991; Muniyappa, ,2003; Naidu et al. , 2006; Prasad et

al., 2006; Rathore et al., 2006 and Singh et al., 1979), where ICAR centers exist. The only work

yet documented on the nematode diseases of plants in Chhattisgarh state include Sao et al.

(2008) and Sahu et al. (2011). Thus, a survey of nematode diseases of vegetable crops grown in

this state becomes practically relevant. The root knot nematode was selected for the purpose.

Community analysis of plant nematodes populations is also important, not only to assess the

pathogenic potential of the nematodes in a particular region, but is also an important criteria for

identification of hotspots of nematode attack.

To determine the plant parasitic nematodes associated with the various vegetable crops, a

survey of vegetable farmlands belonging to Durg district of Chhattisgarh state of India was

31

carried out during 2006-2009. Farmlands of the various villages visited and details of the name

of farm owner, total farm area, topography, soil type, method of irrigation, types and area of

vegetable crops grown, diseases observed and pesticides/insecticides used were recorded.

MATERIALS AND METHODS

The survey of vegetable crops of Durg district for RKN infections was a challenge to be

met because of the vast area involved in vegetable production. The remoteness of the villages

and improper communication network added further challenges to the process.

I. Selection of Diseased Fields

Farmlands growing vegetable crops were chosen and diseased fields were selected on the

basis of above ground symptoms of the crops, such as, wilting, slow growth, stunting and

yellowing of leaves. (Plates 1. 1 to 1. 3).

II. Soil and Root Sample Collection

Soil samples from the associated rhizosphere were collected from a depth of 10-15

centimeters at the rate of one unit sample per acre crop area, besides diseased roots which

were also collected likewise.

Each unit sample was a composite of 20 cores obtained from four corners and centre of the

field.

Both plant and root samples were placed in separate polythene bags, sealed tightly and

labeled with details of host, locality and date of collection.

32

To achieve sufficient accuracy, a relatively large sample size is needed. Usually, these

cannot be processed completely, making it necessary to take sub-samples of the desired

volume or weight.

10 grams of root sample and 200cc. of soil sub samples (prepared from the unit samples)

were stored in polythene bags and kept at 40C in a refrigerator for not more than 7 days

(Plates 1. 4 to 1. 5).

Information on the various factors associated with root knot nematodes, such as,

topographical features, soil texture and methods of irrigation and control were also

collected for epidemiological studies [Table 1.1 (c)-(e)].

III. Extraction of Nematodes

For extraction of nematodes from the soil and root, Cobb’s sieving and modified

Baermann funnel technique (Goodey, 1957; Southey, 1985) was followed by using a

series of sieves (Plates 1. 7 to 1. 10).

Each soil sample was thoroughly mixed and 200cc of soil subsample drawn from the

homogenous mixtures for processing. 10g galled roots were taken and finely chopped.

The representative soil and root sub samples were placed in a plastic tray and soaked in

water for half an hour. The soil lumps were further broken to enable them to form a

suspension (Plate 1. 6).

The soil and root suspension was stirred well and allowed to stand for 15 seconds for the

heavy soil particles to settle at the bottom of the tray. This muddy suspension was then

pored through 25 (600μ) mesh sieve (for large soil particles) and 60 (250μ) mesh sieve

33

(for cysts) arranged one by one and placed on a plastic tray leaving behind the heavy

particles in the previous tray. The process was repeated thrice (Plates 1. 8 to 1. 10).

The whole suspension obtained from 60 mesh sieve was then passed through 325 (45μ),

400 (38μ) and 500 (25μ) mesh sieve arranged one above the other down into the water

which has been poured through it. The suspension obtained from the 500 mesh sieve was

discarded. The debris from the sieves were washed into the beaker and labeled (Plates 1.

11 to1. 15).

An extraction dish was prepared from a 10cm diameter plastic ring and a piece of gauze

cloth and tissue paper attached at the base of ring, with the help of rubber band (Plate 1.

7).

The washed and collected debris was now poured into the extraction dish which was now

placed over the glass bowl containing fresh water and kept for 48 hours for complete

isolation of nematodes (Plate 1. 16).

Care was taken that the base of the extraction dish touches the surface of water in the

bowl (Plate 1. 17).

After 48 hours, the extraction dish was removed slowly from the bowl and the suspension

collected in a beaker and allowed to settle. The excess of water was discarded after

settling.

IV. Killing and Fixing of Nematodes

For killing the nematodes, the beaker containing nematode suspension was kept in a

water-bath and set at temperature 60-70˚C for sometime. Care was taken not to exceed

the specified temperature.

34

Then nematode suspension was cooled and 4-5ml of 4% formalin (10ml formaldehyde

(40%): 90 ml distilled water) was added to 100ml nematode suspension for fixing.

V. Identification and Counting of Nematodes

Few drops of nematode suspension were taken in a watch glass and nematodes picked ,

mounted on glycerin and observed under a Compound Light Microscope, (Labomed CXL

Mono, at 100X and 400X magnifications) and identified (Plate 1. 20).

5ml of killed and fixed nematode suspension was taken in a multichambered counting

dish, mounted on stereoscopic binocular microscope and counted (Plate 1. 18).

Three readings were taken to calculate the average number of nematodes in 100 ml of

suspension. The nematode population per 200 gm of soil and 10 gm root was thus

determined.

V. Staining of Plant material

The root system was washed carefully with water and small roots cut off and kept in hot

(80°C) lacto phenol – cotton blue solution with the help of forceps for 1-3 minutes

allowing the stain to penetrate the material.

The excess stain was washed with water and the material transferred to pure lacto phenol

to remove the stain from the plant tissue, but not from the nematodes and kept for at least

15 minutes.

35

VI. Identification of Meloidogyne Species

The cuticular patterns around the anus and vulva also known as perineal patterns, are

one of the characteristic features studied to identify the Meloidogyne spp. Identification

of species was done microscopically by examination of these patterns of the females after

fixation and staining with Cotton blue –Lactophenol (Plate 1. 22 ) .

The roots with knots were stained in lacto phenol-cotton blue and mature females isolated

and dissected from it.

The posterior half of the body was cut off with a blade: the lower pieces of the cuticle

having perineal patterns were further trimmed to form a square and the inner tissues were

completely removed by a specially designed flexible bristle (Goodey, 1957) (Plate 1.19).

The inner tissue was removed by trimming and the perineal patterns transferred into a

drop of glycerine on a microscope slide. The cover glass was gently placed and sealed

with Zut or glyceel (Jacob & Bezooijen, 1977) and observed under the stereomicroscope

with zoom and camera attachment for microphotography (Carl Zeiss Stemi 2000-C,

1000X magnification and Leica DMLS, 1000X magnification). Identification of species

was done according to Eisenbach (1985) (Plate 1.25- 1. 27).

The identification of the nematodes was further confirmed at the Department of

Nematology, IARI, New Delhi.

VII. Maintenance of Root-knot Nematode Culture

A single egg mass was picked from the infested tomato roots in field

condition and allowed to hatch in fresh water. Then the freshly hatched second stage

juveniles were collected and inoculated into Lycopersion esculentum (Tomato) seedlings

36

(var. Pusa ruby) grown in sterilized soil-manure 3:1 mixture in earthen pots maintained

under glasshouse condition for stock culture. The nematode was identified by close

examination of perineal pattern of the female from the first egg mass collected. It was

confirmed by similar examination of randomly collected females from the innoculum

raised as above (Jacob & Bezooijen, 1977).

VIII. Estimation of Population Density

The population densities of different nematode species in the samples were

calculated using the formulae (Norton, 1978):

Number of samples containing a species

Absolute frequency = ---------------------------------------------------- × 100

Number of samples collected

Frequency of a species

Relative frequency = ----------------------------------------------------- × 100

Sum of the frequencies of all species.

Number of individuals of a species in a sample

Relative density = -------------------------------------------------------- × 100

Total of all individuals in a sample

37

Number of individuals of a species in a sample

Absolute density = ------------------------------------------------------- × 100

Volume or mass or units of the sample

Absolute density x √absolute frequency

Prominence value = ------------------------------------------------------

100

RESULTS

A random survey of the vegetable farmlands belonging to various villages of Durg

district of Chhattisgarh state was carried out during 2006-2009. Farmlands of different villages

visited and details of the name of farm owner, total farm area, topography, soil type, method of

irrigation, types of vegetable crops grown and diseases in crops and pesticides/insecticides used

were recorded and are depicted in Table 1.1 (c) to Table 1.1 (j).

The field survey to study the prevalence of the nematodes in vegetable crops {Table 1.1

(b)} was conducted in 31 farmlands belonging to 23 villages {Table 1.1 (a)}. Out of the total

1132 acres of farm area surveyed, 707 acres were crop area growing 40 different types of

vegetable crops. A total area of 66 acres approximately, was found to be affected by root knot

nematode attack. Among the several genera of vegetable crop plants surveyed L. esculentum, D.

lablab, S. melongena, M. charantia and L. siceraria showed the presence of root galls.

Information about existence of root galls in C. cordifolia and C. papaya in the past months was

obtained from the farmers.

38

Isolation and counting of nematodes from soil and root samples revealed a low infection

range, in L. esculentum (population density of 294 nematodes/10 gm root and 206

nematodes/200cc soil) in Kotni F1, in L. esculentum (950 nematodes/ gm root and 394

nematodes/200cc soil) in Kotni F2 and M. charantia (318 nematode/10 gm root and 343/200cc

soil) in Funda F1 (Paatan). On the other hand, heavy infections were reported at Kotni F4 in L.

esculentum (1155/gm root and 80000/200cc soil), Jatagharra in L. esculentum (7860

nematodes/10gm root and 73104 nematodes /200cc soil), Birejhar in L. esculentum (10000

nematodes/10gm root and 17000 nematodes /200cc soil) and Funda F1 in D. lablab (11997.4

nematodes/10gm root and 8677.2 nematodes /200cc soil). Medium infection range

(2832nematodes/10 gm root and 2678.4 nematodes/200cc soil) was shown at the village Jhola

(Tirga) in L. esculentum, L. siceraria (1320nematodes/10 gm root and 2625 nematodes/200cc

soil) in Funda F2, S. melongena, (1400nematodes/10 gm root and 1073 nematodes/200cc soil)

and L. esculentum (849 nematodes/10gm root and 1392 nematodes /200cc soil) in Temri.

A. Occurrence and Distribution of Nematodes in Vegetable Crops

The nematode populations occurring in vegetable crops of Durg district are shown in

Table 1.2 (a) to Table 1.2 (b). A total of 13 soil and root samples were assembled from different

villages of Durg. Various species of root knot nematodes, including Meloidogyne javanica, M.

incognita, M. arenaria and Meloidogyne spp. were found to be prevalent. Population density

{Table 1.2 (a) and Table 1.2 (b)}, of Meloidogyne spp. (2125/ 200 cc soil + 10 g root) was

observed to be highest in L. esculentum crop at Birejhar. Large numbers of M. incognita (1750)

in Vigna sinensis at Kotni D; M. javanica and M. arenaria (1000 and 650 respectively) in L.

esculentum at Jatagharra C; M. javanica (125) in L. esculentum at Jatagharra D; M. javanica

39

(1250) in Lagenaria siceraria at Kotni E; M. arenaria (550) in Solanum melongena at Jhola A

and M. javanica (500) in L. esculentum at Jhola B and M. incognita (200) and M. javanica (400)

in L. esculentum at Kotni C was observed. Presence of Meloidogyne spp. at Jatagharra B and

Kotni A in L. esculentum (150 and 100 respectively) also observed.

Heavy infestation of reniform nematode, R. reniformis (2000) in Dolichos lablab at Paatan

was observed. Presence of R. reniformis was also observed in L. esculentum at Kotni C (125) and

Jhola B (250); in V. sinensis and L. siceraria at Kotni D (200) and E (222) respectively. The

degree of pathogenicity of most of the pathogenic nematodes varied with locations and the crops

cultivated.

Prevalence of stunt nematode, Tylenchorhynchus indicus was also observed in L.

esculentum at Kotni A (20) and C (100), Jatagharra A (75), Jhola B (110); in D. lablab at Paatan

(150) and in L. siceraria at Kotni E (266). Presence of lesion nematode, Pratylenchus spp. was

observed in beans at Kotni B (125), S. melongena at Jhola A (50), D. lablab at Paatan (56) and L.

siceraria at Kotni E (44). Population of Helicotylenchus spp. (125) and Tylenchidae (50) were

encountered in L. esculentum crop at Jatagharra B.

Presence of free living nematodes was also recorded at certain crops in some

farmlands. Dorylaimids or saprophgous nematodes were observed in L. esculentum crop at Kotni

C (125), Jatagharra A (75) and Jatagharra B (75) and in S. melongena at Jhola A (166).

Mycetophagous nematode, Aphelenchus avenae was observed in L. esculentum at Kotni A (125),

Kotni C (100), Birejhar (100), Jatagharra A (100) and B (125), Jhola B (117) and Jatagharra D

(215), in D. lablab at Kotni B (100) and Paatan (200), in S. melongena at Jhola A (116) and in L.

siceraria at Kotni E (216). Bacteriophagous nematodes, Cephalobids, were observed in L.

esculentum at Kotni A (100) and Birejhar (225) and in D. lablab at Kotni B (50). The predaceous

40

nematode, Mononchids, was also recorded in L. esculentum at Jatagharra A (25) and B (50).

Bacteriophagous nematode, Rhabditids, was found to be associated with L. esculentum at

Jatagharra C (28).

B. Community Analysis of Soil Inhabiting Plant Parasitic Nematodes

An analysis of nematode communities shown in Table 1.2 (c) revealed the presence of 9

species, spread over 6 genera of plant parasitic nematodes (Sahu et al., 2011). Tylenchorhynchus

indicus was the most frequently occurring nematode having absolute an frequency of 46.15% ,

followed by Meloidogyne javanica and Rotylenchulus reniformis each having 38.46% absolute

frequency. These were followed by Pratylenchus spp. (30.77%), Meloidogyne spp. (23.08%) and

M. incognita and M. areneria (15.38%) each. Helicotylenchus spp. and Tylenchidae were least

frequently occurring species (7.69%) each.

Likewise, T. indicus was having highest relative frequency 20.69%, followed by M.

javanica and R. reniformis each having 17.24% relative frequency. These were followed by

Pratylenchus spp. (13.79%), Meloidogyne spp. (10.35%) and M. incognita and M. areneria

(6.90%) each. Helicotylenchus spp. and Tylenchidae were having least relative frequency

(3.45%) each.

M. incognita and Meloidogyne spp. (487.5% and 395.84%) respectively, have the

highest absolute densities, followed by M. javanica (327.5%), M. areneria (300%) and R.

reniformis (279.7%) (Sahu et al., 2011). These were followed by Helicotylenchus spp. (62.5%),

T. indicus (60.06%), Pratylenchus spp. (34.38%) and Tylenchidae (25%). Likewise, the highest

relative density was recorded for M. incognita and Meloidogyne spp. (24.72% and 20.07%

respectively) followed by M. javanica (16.60%), M. areneria (15.21%) and R. reniformis

41

(14.18%). These were followed by Helicotylenchus spp. (3.17%), T. indicus (3.04%),

Pratylenchus spp. (1.74%) and Tylenchidae (1.27%).

Considering both frequencies and densities (Sahu et al., 2011), the highest prominence

value (203.10) was recorded for M. javanica followed by M. incognita (191.18), Meloidogyne

spp. (190.17) and R. reniformis (173.46). These were followed by M. areneria (117.65), T.

indicus (40.80), Pratylenchus spp. (19.07), Helicotylenchus spp. (17.33) and Tylenchidae (6.93).

The highest relative prominence value (21.16%) was recorded for M. javanica followed by M.

incognita (19.92%), Meloidogyne spp. (19.82%) and R. reniformis (18.07%). These were

followed by M. areneria (12.26%), T. indicus (4.25%), Pratylenchus spp. (1.99%),

Helicotylenchus spp. (1.87%) and Tylenchidae (0.72%).

C. Crop-wise distribution:

The predominant plant parasitic nematodes associated with various crops are listed in

Table 1.2 (d). M. incognita, M. javanica, M. areneria and Meloidogyne spp. were found to be

predominant on L. esculentum; M. areneria on S. melongena; M. incognita on V. sinensis and M.

javanica on L. siceraria. R. reniformis was found to be predominant on L. esculentum, D. lablab,

S. melongena, V. sinensis and L. siceraria and T. indicus on L. esculentum, D. lablab, S.

melongena and L. siceraria. Helicotylenchus spp. and Tylenchidae were also found to be

associated with L. esculentum; Pratylenchus spp. with D. lablab, S. melongena and L. siceraria

(Sahu et al., 2011).

42

D. Hot-spots of nematode infestation:

The hot-spots of nematode infestations were identified based on the nematode densities

with populations exceeding the damage threshold (> 1/100 g soil), in order to map out the

possible problem areas in Table 1.2 (e). It was revealed that hot- spots for M. javanica were

Kotni C, Jhola B, Jatagharra C and D and Kotni E on L. esculentum and L. siceraria crops. Kotni

C and Kotni D were the problem areas for M. incognita on L. esculentum and V. sinensis. The

hot-spot for M. areneria was at Jatagharra C and Jhola A on L. esculentum and S. melongena

respectively. Severe infestation of Meloidogyne spp. was observed on L. esculentum in Kotni A,

Birejhar and Jatagharra B. The hot-spots for R. reniformis were Kotni C and Jhola B for L.

esculentum, Paatan for D. lablab, Kotni D for V. sinensis and Kotni E for L. siceraria. Severe

infestation of T. indicus was observed on Kotni A, Kotni C, Jatagharra A and Jhola B for L.

esculentum, Paatan for D. lablab, and Kotni E for L. siceraria. Infestation of Pratylenchus spp.

was observed on Kotni B and Paatan in D. lablab and Jhola A and Kotni E in S. melongena and

L. siceraria respectively. Furthermore, Helicotylenchus spp. and Tylenchidae may pose threat to

the L. esculentum cultivation in Jatagharra B.

DISCUSSION

Sitaramaiah (1984) reviewed the plant parasitic nematodes associated with different crops

in various parts of India. Singh and Satyapriya (2008) were the first to report the occurrence of

M. incognita on bean and pea from Jammu, India. Roy et al. (2008) were the first to notice

severe infestation of M. incognita in Swertia chirayita (Chiretta) on Sherpa Gaon village of Lava

region (Eastern Himalayan range) of Kalimpong Block II. Ali et al. (2006) determined the

community analysis of plant parasitic nematodes associated with the rhizosphere of pulse crops

43

viz., pigeon pea, chickpea, lentil and field pea in Hamirpur district, Uttar Pradesh. Lone et al.

(2006) conducted a field survey to know the association of reniform nematode (Rotylenchulus

reniformis) with the available crops in and around Udaipur district of Rajasthan.

Rathour et al. (2006) analyzed the nematode communities during survey of Champawat

district of Uttaranchal, India and revealed the presence of several plant parasitic nematodes

associated with different crops. Predominant nematodes were: Meloidogyne spp. (M. incognita

and M. javanica) associated with chilli, okra, papaya and soybean; Quinisulcius acti with maize,

chilli, okra and pumpkin; Rotylenchulus reniformis with castor, papaya and okra;

Helicotylenchus spp. (H. dihystera and H. pseudorobustus) with pumpkin, okra, papaya and

soybean; Hemicriconemoides mangiferae and Pratylenchus curvitatus with mango and litchi;

Trichodorus pakistanensis with litchi, soybean and pumpkin and Hoplolaimus seinhorsti and

Tylenchorhynchus indicus were found to be associated with okra and mango respectively.

Likewise, in our present findings also the different species of Meloidogyne (M. incognita, M.

javanica, M. arenaria and Meloidogyne spp.) are predominant and found associated with

L.esculentum, L.siceraria, S.melongena and V. sinensis; R. reniformis with L. esculentum, D.

lablab, L.siceraria and V. sinensis and T. indicus with L.esculentum, L.siceraria, D. lablab and

V. sinensis.

Sundraraju (2006) surveyed the plant parasitic nematode species associated with main

banana growing districts of Andhra Pradesh and recorded maximum frequency, absolute

frequency, absolute density and prominence value for M. incognita followed by P. coffeae.

Similarly, in our present study the maximum absolute density was recorded for M. incognita

(487.5) followed by Meloidogyne spp. (395.84) < M. javanica (327.5) < M. arenaria (300). Roy

et al. (2007) studied the occurrence, distribution and community analysis of plant parasitic

44

nematodes associated with leguminous vegetable crops in seven districts of West Bengal, India

and observed that Nadia district was hot-spot for R. reniformis while Malda, 24 Parganas (North

and South), Burdwan and Murshidabad were found as hot-spots for Meloidogyne spp. Likewise,

in our investigation huge populations of Meloidogyne spp. (2125 J2/200cc soil +10 g roots) and

M. incognita (1750 J2/200cc soil +10 g roots) were encountered from Birejhar and Kotni D

respectively. According to Saggito and Pervertin, 1988 (cited in Roy et al., 2007), one and half

second stage juveniles of root-knot nematodes per cc of soil can be safely considered as their

economic threshold level. Hence, the regions having root-knot nematodes population above

300/200 cc of soil can be undoubtedly treated as the hot spots.

Patel et al. (2007) reported highest frequency of Meloidogyne spp. followed by

Pratylenchus spp. in Diu an union territory of India. Naidu et al. (2007) reported highest absolute

frequency, relative frequency, relative density and prominence value for root-knot nematodes in

Chittoor district of Andhra Pradesh, India. This corroborates with our findings of Durg district of

Chhattisgarh, India. In our investigation also highest absolute frequency, relative frequency,

absolute density, relative density and prominence value was recorded for root-knot nematodes.

Sudheer et al.(2008) analyzed the community structure of plant parasitic nematodes in

selected districts of Andhra Pradesh, India and revealed that M. incognita was predominant in

Anantpur and Chittoor, R. reniformis in Guntur and Mahaboobnagar, Helicotylenchus spp. in

Kadapa, Kurnool, Nalgonda and Prakasam and M. graminicola in Nellore. Nath et al. (2008)

studied the occurrence and distribution of plant parasitic nematodes associated with litchi

plantations in North Tripura district of India and observed that Hemicriconemoides litchi, R.

reniformis and M. incognita were the most abundant, frequent and prominent nematodes.

45

Rathour et al. (2010) reported Meloidogyne incognita to be the most frequently occurring

phytonematode in Madhya Pradesh with the highest absolute frequency (50), followed by

Rotylenchulus reniformis (40.38) and Helicotylenchus dihystera (23). The maximum absolute

density was recorded for R. reniformis followed by H. dihystera and Tylenchorhynchus indicus

with 205, 121 and 110 individuals per 100g soil, respectively. The highest prominence value was

recorded for M. incognita (17.12), followed by H. dihystera (13.78) and Hoplolaimus indicus

(11.20). In the present case, prominence values of M.javanica (203.10) and M.incognita (191.18)

were found to be highest among all nematodes present, being far greater than the values reported

by the above mentioned authors and hence are a matter of grave concern.

Khan et al. (2010) reported the presence of only Meloidogyne spp. and M.incognita in

vegetable crops of Durg district of Chhattisgarh. In our work the presence of R.reniformis,

T.indicus, Helicotylenchus spp., Tylenchidae and Pratylenchus spp . is additionally reported.

The results obtained in the present case run in accordance with those published in our

previous work Sao et al. (2008), showing highest average population density (2169

nematodes/10 gm root and 29993 nematodes / 200 cc soil) in the village Funda (Paatan) .

Among the several genera of vegetable crop plants surveyed Lycopersicon esculentum, Dolichus

lablab and Momordica charantia showed the presence of root galls with the highest average

population density being in Dolichus lablab in the month of January. The hot spots of nematode

infestations marked in the present case prove beyond doubt that the vegetable crops in district

Durg of Chhattisgarh are severely infested with phytonematodes. Most of the species recorded in

the present study particularly, root knot nematodes, are highly pathogenic and population is

beyond the damage threshold level. Hence, their occurrence may pose a serious threat to the

affected crops and need prompt attention of farmland owners and researchers.

46

TABLES AND FIGURES

47

Table 1.1(a) - List of villages surveyed in district Durg Dist. during 2006 to 2009.

Symbol Village Symbol Village

V1 Kotni V13 Bangaon(Daundi)

V2 Arasnara V14 Bhaisbode(Daundi)

V3 Karanja Bhilai V15 Chhatagarh

V4 Ganiyari V16 Devkot(Gurur)

V5 Nagpura V17 Risama(Anda)

V6 Funda(Paatan) V18 Matra(Dhamdha)

V7 Jatagharra(Dhamdha) V19 Hardi(Dhamdha)

V8 Jhola(Tirga) V20 Mohlai

V9 Parras(Baalod) V21 Nevnara

V10 Jhurri(Baalod) V22 Temri

V11 Jhalmala(Baalod) V23 Birejhar

V12 Khurmuda(Berla)

48

Table 1.1(b). List of crop plants surveyed

SYMBOL COMMON NAME SCIENTIFIC NAME

C1 Tomato Lycopersicon esculentum

C2 Bitter gourd Momordica charantia

C3 Beans Dolichos lablab

C4 Cow pea Vigna sinensis

C5 Little gourd Coccinia cordifolia

C6 Brinjal Solanum melongena

C7 Cauliflower Brassica oleracea var. botrytis

C8 Cabbage Brassica oleracea var.capitata

C9 Ginger Zingiber officinale

C10 Papaya Carica papaya

C11 Pea Pisum sativium

C12 Cucumber Cucumis sativum

C13 Onion Allium cepa

C14 Knol khol Brassica oleracea var. gongylodes

C15 Banana Musa paradisica

C16 Bottle gourd Lagenaria siceraria

C17 Chilli Capsicum annum

C18 Potato Solanum tuberosum

C19 Water melon Citrullus vulgaris

C20 Bengal gram Cicer arietinum

49

Table 1.1(b). List of crop plants surveyed (contd.)

SYMBOL COMMON NAME SCIENTIFIC NAME

C21 Mustard Brassica campestris

C22 Wheat Triticum aestivum

C23 Radish Raphanus sativus

C24 Jack fruit Artocarpus heterophyllus

C25 Lady's finger Hibiscus esculentus

C26 Coriander Coriandrum sativum

C27 Pumpkin Cucurbita pepo

C28 Kakri Cucumis melo var.utilissimus

C29 Guar bean Cyamopsis tetragonoloba

C30 Fenugreek Trigonella gracium

C31 Sugarcane Saccharum officinarum

C32 Linseed Linum usitatissimum

C33 Spinach Spinacia oleracea

C34 Amaranthus Amaranthus spp.

C35 Sesame(Til) Sesamum indicum

C36 Maize Zea mays

C37 Pigeon pea Cajanus cajan

C38 Sponge gourd Luffa cylindrica

C39 Mung bean Vigna radiata

C40 Rice Oryza sativa

50

Table 1.1(c).-List of Villages surveyed in District Durg during 2006-2009

Village TFA(Acres)

Topography Soil type Irrigation Control Crops surveyed NPD(per 200 cc soil and 10g roots)

Kotni F1 23 Riverside farm Sandy Drip Biocontrol*

L.esculentum 500M.charantia -D.lablab -V.sinensis -C.cordifolia -S.melongena -

Arasnara F1 9 Plain land Black Drip Nil B.oleracea var. botrytis -M.charantia -

F2 27 Plain land Black Drip Nil B.oleracea var. botrytis -

B.oleracea var.capitata -

Z.officinale -

C.papaya -

C.cordifolia -

M.charantia -

51

Table 1.1(d).-List of Villages surveyed in District Durg during 2006-2009 (contd.)

Village TFA(Acres)

Topography Soil type Irrigation Control Crops surveyed NPD(Per 200 cc soil+10groots)

Karanja BhilaiF1

14 Plain land Brown Drip Nil P.sativum -D.lablab -C.sativa -C.cordifolia -B.oleracea var. botrytis -A.cepa -B.oleraceavar. gongylodes

-

F2 25 Plain land Sandy Drip Nil S.melongena -

B.oleracea var. botrytis -

D.lablab -

C.cordifolia -

M.paradisica -

52

Table 1.1(e). -List of Villages surveyed in District Durg during 2006-2009(contd.)

Village TFA(Acres)

Topography Soil type Irrigation Control Crops surveyed NPD (200cc soil+10g roots)

Ganiyari 45 Plain land Black Drip Nil B.oleracea var. botrytis -C.papaya -C.cordifolia -L.siceraria -M.charantia -D.lablab -C.annum -S.tuberosum -B.oleracea var.capitata -L.esculentum -

Nagpura 50 Plain land Kanhar(Clay)

Drip Nil C.papaya -C.cordifolia -L.esculentum -M.paradisica -D.lablab -L.siceraria -B.oleracea var.gongylodes -

Funda(Paatan) 85 Plain land Semi sandy(Matasi)

Drip Biocontrol

D.lablab 20674.6

L.siceraria -

M.charantia 661

C.annum -

M.paradisica -

L.esculentum -

D.lablab -

53

Table 1.1(f).-List of Villages surveyed in District Durg during 2006-2009(contd).

Village TFA(Acres)

Topography Soil type Irrigation Control Crops surveyed NPD (200cc soil+10g roots)

Jatagharra(Dhamdha) 13 Plain land Black Drip Ferodon L.esculentum 80964Jhola (Tirga) 100 Plain land Brown sandy Flood and drip Nil V.sinensis -

D.lablab -C.cordifolia -M.paradisica -L.esculentum 5510.4P.plebejum -B.oleracea var. botrytis -C.vulgaris -C.annum -C.arietinum -B.campestris -

Parras(Balod) 3 Sloppy terrain Sandy Flood Nil L.esculentum -A.cepa -C.pepo -C.melo var.utilissimus -

Jhurri (Balod) 7 Plainland Sandy Flood Nil S.melongena -

L.siceraria -

M.charantia -

V.sinensis -

C.tetragonoloba -

C.sativum -

T.gracium -

54

Table 1.1(g).-List of Villages surveyed in District Durg during 2006-2009(contd.)

Village TFA(Acres)

Topography Soil type Irrigation Control Crops surveyed NPD (200cc soil +10g roots)

Jhalmala(Baalod)

2.5 Plain land

Sandy

Flood

Nil L.esculentum -B.oleracea var. botrytis -C.annum -A.cepa -C.sativum -D.lablab -H.esculentus -V.sinensis -C. pepo -R.sativus -

Khurmuda(Berla) F1

20 Plain land Sandy Drip Nil B.oleracea var.botrytis -S.melongena -

F2 60 Plain land Sandy Flood Nil S.melongena -B.oleracea var.gongylodes -L.esculentum -S.officinarum -C.arietinum -L.usitatissimum -

F3 100 Plain land Sandy Flood Nil C.arietinum -L.usitatissimum -S.melongena -L.siceraria -C.melo -C.papaya -C.annum -

F4 30 Plain land Sandy Flood Nil

C.arietinumC.sativumL.usitatissimum

---

55

Table 1.1(h).-List of Villages surveyed in District Durg during 2006-2009(contd.)

Village TFA(Acres) Topography Soil type Irrigation Control Crops surveyed NPD (200cc soil +10g roots)

Bangaon(Daundi)

10 Plain land

Sandy Flood Nil

B.oleracea var. botrytis

-

B. oleracea var.gongylodes -A.cepa -L.esculentum -S.oleracea -C.sativum -D.lablab -R.sativus -O.sativa -

Bhaisbode(Daundi)

20 Plain land Kachhar FloodNil

L. esculentum -O.sativa -S.oleracea -C.sativum -Amaranthus spp. -

ChhatagarhF1

8 Sloppyriverside

Black Flood and Drip

Nil

S.melongena -M.charantia -C.cordifolia -A. heterophyllus -

F2 15 Sloppy riverside Kachar Flood Nil C.cordifolia -

56

Table 1.1(i). - List of Villages surveyed in District Durg during 2006-2009 (contd).

Village TFA(Acres) Topography Soil type Irrigation Control Crops surveyed NPD(200cc soil+10g roots)

Hardi(Dhamdha)

16 Plainland

Black

flood

Nil

L.esculentum -

H.esculentus -A.cepa -T.gracium -C.sativum -V.sinensis -S.melongena -B.campestris -T.aestivum -C.arietinum -

Mohlai 1.5 Riverside

Sandy loam

flood

Nil

V.sinensis -C.annum -S.melongena -C.cordifolia -M.charantia -C.papaya -L.siceraria -

Kotni F2 22 Riverside

Brown drip Nil L.esculentum 1344S.melongena -

Kotni F3 24 Riverside

Brown drip Nil C.cordifolia -

57

Table 1.1(j). - List of Villages surveyed in District Durg during 2006-2009 (contd.)

Village TFA(Acres) Topography Soil type Irrigation Control Crops surveyed NPD(200cc soil +10g roots)

Nevnara 60 Plain land Blacksoil

Flood Nil C.pepo -L.cylindrica -

Kotni F4 23 Plain land Kanhar Drip Nil L.siceraria -D.lablab -B.oleracea var. botrytis -L.esculentum 81155

F5 25 Plain land Kanhar Drip Nil M.charantia -C.sativum -C.cordifolia -

Funda F2(Paatan)

65 Plain land Kanhar Drip Nil M.charantia -L.siceraria 3945

Temri 50 Plain land Black soil Drip Nil C.annum -C.papaya -Capsicum spp. -L.esculentum 2241M.charantia -S.melongena 2473

Birejhar 60 Plain land Kanhar Drip Nil L.siceraria -

C.pepo -

L.esculentum 27000

S.melongena -

58

Table 1.2(a). - Occurrence of nematode populations per 200cc soil+10 g root in vegetable crops in district Durg of Chhattisgarh, India.

Abbreviations used- Meloidogyne spp. (MG)-*M.incognita;**M.javanica; ***M.arenaria ; Rotylenchulus reniformis(RR), Tylenchorhynchus indicus(TI);; Pratylenchus spp. (PT); Helicotylenchus spp (HT); Tylenchidae (TY) ;Dorylymids(DL); A . avenae(AA);Cephalobid (CB);Mononchids(MC); Rhabditids (RB)

Village CropPlant Parasitic Nematodes Free Living NematodesMG RR TI PT HT TY DL AA CB MC RB

Kotni A

Kotni B

Kotni C

Birejhar

Jatagharra A

Jatagharra B

Jhola A

Jhola B

L.esculentum

D.lablab

L.esculentum

L.esculentum

L.esculentum

L.esculentum

S.melongena

L.esculentum

100

-

200 *

400**

2125

-

150

550***

500**

-

-

125

-

-

-

-

250

20

-

100

-

75

-

-

110

-

125

-

-

-

-

50

-

-

-

-

-

-

125

-

-

-

-

-

-

-

50

-

-

-

-

125

-

75

75

166

-

125

100

100

100

100

125

116

117

100

50

-

225

-

-

-

-

-

-

-

-

25

50

-

-

-

-

-

-

-

-

-

-

59

Table 1.2(b). -Occurrence of nematode populations per 200cc soil+10 g root in vegetable crops in district Durg of Chhattisgarh, India (Contd.).

Abbreviations used- Meloidogyne spp. (MG)-*M.incognita;**M.javanica; ***M.arenaria ; Rotylenchulus reniformis(RR), Tylenchorhynchus indicus(TI);; Pratylenchus spp. (PT); Helicotylenchus spp (HT); Tylenchidae (TY) ;Dorylymids(DL); A . avenae (AA);Cephalobid (CB);Mononchids(MC); Rhabditids (RB).

Village CropPlant Parasitic nematodes Free Living NematodesMG RR TI PT HT TY DL AA CB MC RB

Paatan

Jatagharra C

Kotni D

Jatagharra D

Kotni E

D. lablab

L. esculentum

V. sinensis

L. esculentum

L.siceraria

-

1000**

650***

1750*

125**

1250**

2000

-

200

-

222

150

-

-

-

266

56

-

-

-

44

-

-

-

-

-

-

-

-

-

-

-

-

-

-

-

200

-

-

215

216

-

-

-

-

-

-

-

-

-

-

-

28

-

-

-

60

Table 1.2(c). - Community analysis of plant parasitic nematodes associated with different crops in district Durg of Chhattisgarh.

Sl.No.

Nematode Average(Range)

AbsoluteFrequency

RelativeFrequency

AbsoluteDensity

RelativeDensity

ProminenceValue

RelativeProminenceValue

1.

2.

3.

4.

5.

6.

7.

8.

9.

Meloidogyne incognita

M. javanica

M. arenaria

Meloidogyne spp.

Rotylenchulusreniformis

Tylenchorhynchusindicus

Pratylenchus spp.

Helicotylenchus spp.

Tylenchidae

975(200-1750)655(125-1250)

600(550-650)

791.67(100-2125)

559.4(125-2000)

120.17(20-266)

68.75(44-125)

125

50

15.38

38.46

15.38

23.08

38.46

46.15

30.77

7.69

7.69

6.90

17.24

6.90

10.35

17.24

20.69

13.79

3.45

3.45

487.5

327.5

300

395.84

279.7

60.06

34.38

62.5

25

24.72

16.60

15.21

20.07

14.18

3.04

1.74

3.17

1.27

191.18

203.10

117.65

190.17

173.46

40.80

19.07

17.33

6.93

19.92

21.16

12.26

19.82

18.07

4.25

1.99

1.81

0.72

61

Table 1.2(d). - Predominant plant parasitic nematode species associated with vegetable crops in district Durg of Chhattisgarh

SNo. Crops Predominant Nematode Species Other Nematode Species

1.

2.

3.

4.

5.

L. esculentum

D. lablab

S.melongena

V. sinensis

L.siceraria

Meloidogyne incognita, M. javanica, M. arenaria, Meloidogyne spp.,Rotylenchulus reniformis, Tylenchorhynchus indicus

Rotylenchulus reniformis, Tylenchorhynchus indicus

Meloidogyne arenaria, Rotylenchulus reniformis, Tylenchorhynchus indicus

Meloidogyne incognita, Rotylenchulus reniformis

Meloidogyne javanica, Rotylenchulus reniformis, Tylenchorhynchus indicus

Helicotylenchus spp., Tylenchidae

Pratylenchus spp.

Pratylenchus spp.

Pratylenchus spp.

62

Table 1.2(e). - Hot-spots of nematode infestation in various vegetable crops in district Durg of Chhattisgarh

Crops

Nematode spp./ Village

M.incognita M. javanica

M.arenaria Meloidogyne spp.

R.reniformis

T.indicus

Pratylenchus spp.

Helicotylenchus spp.

Tylenchidae

L. esculentum

Kotni C Kotni CJhola BJatagharra CJatagharra D

Jatagharra C Kotni ABirejharJatagharra B

Kotni CJhola B

Kotni AKotni CJatagharra AJhola B

- Jatagharra B Jatagharra B

D. lablab - - - - Paatan Paatan Kotni BPaatan

- -

S.melongena

- - Jhola A - - - Jhola A - -

V. sinensis Kotni D - - - Kotni D - - - -

L.siceraria

- Kotni E - - Kotni E Kotni E Kotni E - -

63

64

PLATES

65

Plate1.1. An infested Tomato field

Plate1.2. An infested plant of Tomato

Plate1.3. An infested root of Tomato showing galls.

66

Plate1.4. Storage of soil samples in plastic bags.

Plate1.5. Storage of root samples in plastic bags.

Plate1.6. Soil samples pre-soaked in trays.

67

Plate1.7.Extraction dishes made of pipe and tissue paper supported by gauze cloth.

Plate1.8. Sieves (25 and 60 mesh size)

Plate1.9. Sieves (325 and 400 mesh size)

68

Plate1.10. Sieve (500 mesh sizes)

Plate1.11. Extraction process-Step 1

Plate1.12. Extract from step 1 is collected in a plastic tub

69

Plate1.13. Extraction process-Step 2

Plate1.14. Extract from step 2 collected in a tub.

Plate1.15. Extraction with repeated washings

70

Plate1.16.Extraction process Step 3 (materials collected being poured into the extraction dish).

Plate1.17. Extraction apparatus placed in a glass bowl containing water with its base touching the surface of water in the bowl.

Plate1.18. Multi-chambered counting dish

71

Plate1.19. Handling needles (flexible bristle)

Plate1.20. Nematode counting

Plate1.21. Nematode Stock Culture maintained in Tomato (var. Pusa Ruby)

72

Plate1. 22. Female

Plate1. 23. Egg

Plate1.24.Second stage juveniles (J2)

73

Plate1. 25. Perineal patterns (Meloidogyne arenaria)

Plate1. 26. Perineal patterns (Meloidogyne incognita)

Plate1. 27. Perineal patterns (Meloidogyne javanica)

74

Plate1. 28. Net house