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HEALTH ASSESSMENT OF LIVISTONA CHINENSIS AND CYCAS REVOLUTA IN
UNIMAS
Siti Nadhirah Binti Ismail
Bachelor of Science with Honours
(Plant Resource Science and Management)
2015
Health Assessment of Livistona chinensis and Cycas revoluta in UNIMAS
SITI NADHIRAH BINTI ISMAIL
(38771)
This report is submitted in partial fulfilment of the
requirement for the Degree of Bachelor of Science with Honours
(Plant Resource Science and Management)
Supervisor: Dr. Mohamad Hasnul Bin Bolhassan
Plant Resource Science and Management
Department of Plant Science and Environmental Ecology
Faculty of Resource Science and Technology
UNIVERSITI MALAYSIA SARAWAK
2014/2015
ACKNOWLEDGEMENT
Bismillahirrahmanirrahim
I am grateful to all those concerned who had made this dissertation possible. First of all, I
would like to thank upon Allah SWT for His willing and blessing for me to complete this
Final Year Project. I am very grateful to have Dr. Mohamad Hasnul Bolhassan as my
supervisor, for his guidance, advices, knowledge, and non-stop support to complete this
project. His dedicated supervision has made things clear and I gain new knowledge and
experience throughout the process of completion of this project.
I am also very grateful for having Dr. Siti Rubiah Zainudin as my co-supervisor. Thanks for
her guidance, ideas, meaningful criticism and also her encouragement for me to finish my
project. Her patience and understanding make me comfortable to work under her supervision.
My special recognition goes to my mother, Puan Zaiton Sam and my family for giving me
support and encourages me to complete this project. I would like to convey my sincere thanks
to my partner Nur Fatihah Khair Yusof for always there beside me from the starting of this
project until the successful completion of this project.
My warmest thanks to the UNIMAS landscaping unit management staff for sharing
information and cooperation in technical support. Last but not least, my warmest thanks for all
those who had help me either directly or indirectly upon the completion of this Final Year
Project. Thank you.
DECLARATION
I hereby declare that the thesis is based on my original work. All the quotations and citations
have been duly acknowledge. No portion of the work referred to this dissertation has been
previously or concurrently submitted for any other degree programs in UNIMAS or other
institutions of higher learning.
_____________________
Siti Nadhirah Binti Ismail
Plant Resource Science and Management
Faculty of Resource Science and Technology
Universiti Malaysia Sarawak (UNIMAS)
APPROVAL SHEET
Name of Candidate: Siti Nadhirah Binti Ismail
Title of Dissertation: Health Assessment of Livistona chinensis and Cycas revoluta in
UNIMAS
___________________________
Dr. Mohamad Hasnul Bolhassan
Supervisor
Plant Resource Science and Management
Faculty of Resource Science and Technology
Universiti Malaysia Sarawak (UNIMAS)
i
Table of Contents
Table of Contents…………………………………………………………………………….....i
List of Abbreviations…………………………………………………………………………...ii
List of Tables, Figures and Plates..............................................................................................iii
Abstract………………………………………………………………………………………...vi
1.0 Introduction…………………………………………………………....…………………...1
1.1 Problem Statement………………………………………………………………….1
1.2 Objectives…………………………………………………………………………..2
2.0 Literature Review…………………………………………………………………………..2
2.1 Urban Forest………………………………………………………………………..2
2.2 Ornamental Plants…………………………………………………………………..2
2.3 Benefits of Ornamental Plants…………………….………………………………..3
2.3.1 Aesthetical Value ………………….…………………………………...3
2.3.2 Noise Reduction …………….………………………………………....3
2.3.3 Air Quality Improvement……...…………………………………….…4
2.3.4 Shading and Cooling…………………………………………………...4
2.4 Palm……...……...………………………………………………………………….5
2.4.1 Livistona chinensis…………………………...………………………...6
2.4.2 Cycas revoluta……………………………………………………….....7
2.5 Common Urban Plant Diseases…………………………………………………….8
2.5.1 Ganoderma zonatum……………………………………………………8
2.6 Main Factors Affecting the Health Status of Urban Plant...………………………..9
2.6.1 Climate Change…………………………………………………….…..9
2.6.2 Nutrient Deficiencies……………………………………………….…10
2.6.3 Biotic Factors………………………………………………………….12
3.0 Materials and Method……………………………………………………………………..15
3.1 Study Area………………………………………………………………………...15
3.2 Physical Assessment...…………………………………………………………….17
3.2.1 Diameter at Breast Height, DBH……………………………………...18
3.2.2 Height…………………………………………………………………18
3.2.3 Planting Distance……………………………………………………...19
3.2.4 Chlorophyll Content…………………………………………………..19
3.2.5 Tree Health Status…………………………………………………….20
4.0 Results…………………………………………………………………………...……......22
5.0 Discussion…………………………………………………………………………………36
6.0 Conclusion………………………………………………………………………………...47
7.0 Recommendations………………………………………………………………………...48
8.0 References………………………………………………………………………………...49
9.0 Appendices……………………………………………………………………………..…52
ii
List of Abbreviations
UNIMAS – Universiti Malaysia Sarawak
DBH – Diameter at Breast Height
SPAD – Soil Plant Analysis Development
CAIS – Center of Academic, Information and Services
CTF – Central of Teaching Facilities
FCSHD – Faculty of Cognitive Science and Human Development
FE – Faculty of Engineering
FACA – Faculty of Applied and Creative Art
FMHS – Faculty of Medicine and Health Science
N – Nitrogen
K – Potassium
Mg – Magnesium
Mn – Manganese
Fe – Iron
Ca – Calcium
B – Boron
iii
List of Tables, Figures and Plates
Tables
Table 1: Symptoms of Nutrients Deficiencies of Palm Species. 11
Table 2: Symptoms of Fungal and Bacterial Infection of Urban Tree. 12
Table 3: Palm Species Planted and the Distribution in UNIMAS. 16
Table 4: Distribution of Chinese Palm. 17
Table 5: Distribution of Cycad Palm. 17
Table 6: Ranking System for Tree Health Status. 21
Table 7.1: DBH and height range of Chinese Palm at Site 1 22
Table 7.2: Chlorophyll content of Chinese Palm at Site 1 23
Table 8: DBH and height range of Chinese Palm at Site 3 25
Table 9: Physical Data of Chinese Palm at Site 5 30
Table 10: Physical Data of Chinese Palm at Site 6 31
Table 11.1: Physical Identification Data Collection (Site No. 1- CAIS) 53
Table 11.2: Physical Identification Data Collection (Site No. 2- University House) 55
Table 11.3: Physical Identification Data Collection (Site No. 3- Jalan Ensurai) 56
Table 11.4: Physical Identification Data Collection (Site No. 4- FACA lower ground floor) 58
Table 11.5: Physical Identification Data Collection (Site No. 5- FCSHD parking lot) 59
Table 11.6: Physical Identification Data Collection (Site No. 6- CTF2 parking lot) 60
Table 11.7: Physical Identification Data Collection (Site No. 7- FE parking lot) 61
Table 11.8: Physical Identification Data Collection (Site No. 8- FMHS within buildings) 62
iv
Figures
Figure 1: Height calculation 19
Figure 2: Overall Health Status of Chinese Palm in UNIMAS. 35
Figure 3: Overall Health Status of Cycad Palm in UNIMAS 35
Figure 4: Map of UNIMAS West Campus 52
Figure 5: Map of planting position of Chinese Palm at CAIS 54
Figure 6: Map of planting position of Cycad Palm at University House 55
Figure 7: Map of planting position of Chinese Palm and Cycad Palm at Jalan Ensurai 57
Figure 8: Map of planting position of Cycad Palm at FACA 58
Figure 9: Map of planting position of Chinese Palm at FCSHD 59
Figure 10: Map of planting position of Chinese Palm at CTF2 60
Figure 11: Map of planting position of Cycad Palm at FE 61
Figure 12: Map of planting position of Cycad Palm at FMHS 62
v
Plates
Plate 1: Chinese Palm planted at CTF2, UNIMAS. 6
Plate 2: Cycad Palm planted near the lake of UNIMAS. 7
Plate 3: Suunto clinometer. 18
Plate 4: SPAD Meter. 20
Plate 5: Technique to use SPAD 20
Plate 6: Chinese Palm planted at CAIS walking pathway. 23
Plate 7: Single potted Cycad Palm 24
Plate 8(a): Yellowish tip leaves of Chinese Palm. 26
Plate 8(b): Hollow stem. 27
Plate 8(c): Snails feed on the hole 27
Plate 8(d): Three Cycad Palm planted at Jalan Ensurai. 28
Plate 9(a): Ganoderma infection at stem base (C11). 29
Plate 9(b): Ganoderma conk formation (C12). 29
Plate 9(c): Stem base affected by Ganoderma (C11). 29
Plate 9(d): Ganoderma conk (C12). 29
Plate 10: Yellowing tip of Chinese Palm leaves 31
Plate 11(a): Chinese Palm in roundabout (L1 and L2). 32
Plate 11(b): Browning color with dead leaves (L3). 32
Plate 12: Tip necrosis of Cycad Palm leaves (C1). 33
Plate 13: Cycad Palm planted in potted form at Faculty of Medicine. 34
vi
Health Assessment of Livistona chinensis and Cycas revoluta in UNIMAS
Siti Nadhirah Binti Ismail
Plant Resource Science and Management
Faculty of Resource Science and Technology
Universiti Malaysia Sarawak
Abstract
Urban trees planted in the urban landscape are usually beautiful, of high aesthetic values and should be
free from pest and diseases. However, due to several biotic and abiotic factors, urban trees are
sometimes infected with pest and diseases. The objective of this study is to assess the health status of
69 Livistona chinensis (Chinese Palm) and 24 Cycas revoluta (Cycad Palm) planted in different sites
within UNIMAS campus. In this study, the health assessment of the palms were measured including of
DBH, height, planting distance, chlorophyll content, health status and symptoms of infection. The
infected part of palm with Ganoderma conk formation was the indicator that the palm was affected by
Ganoderma butt rot disease. Overall, Chinese Palm planted in UNIMAS was in good condition
although suffering with nitrogen deficiencies and attacked by palm borer beetle while Cycad Palm was
in fair condition probably due to potassium deficiencies and Ganoderma butt rot disease. This health
assessment will aids the management in UNIMAS in planning a more proper palm health management.
Key words: Disease, Livistona chinensis, Cycas revoluta, Ganoderma, tree health status, disease
management.
Abstrak
Pokok urban yang ditanam di kawasan lanskap adalah cantik, tinggi nilai estetika dan seharusnya
bebas dari perosak dan penyakit. Namun, berikutan faktor biotik dan abiotik, pokok urban
berkemungkinan diserang oleh perosak dan penyakit. Objektif kajian ini adalah untuk menilai taraf
kesihatan 69 Livistona chinensis (Chinese Palm) dan 24 Cycas revoluta (Cycad Palm) yang ditanam
di kawasan yang berbeza dalam kampus UNIMAS. Di dalam kajian ini, panilaian taraf kesihatan
pokok palma dinilai dari aspek DBH, ketinggian, jarak penanaman, kadar klorofil, taraf kesihatan dan
gejala jangkitan penyakit. Bahagian pokok palma yang dijangkiti dengan pembentukan jasad berbuah
Ganoderma merupakan petunjuk bahawa pokok tersebut telah dijangkiti penyakit Ganoderma reput
batang. Secara keseluruhannya, Chinese Palm yang ditanam di UNIMAS berada dalam keadaan baik
walapun mengalami kekurangan nitrogen dan serangan kumbang pengorek palma manakala Cycad
Palm berada dalam keadaan memuaskan kerana berkemungkinan mengalami kekurangan potassium
dan penyakit Ganoderma reput batang. Kajian ini akan membantu pihak pengurusan di UNIMAS
dalam merancang pengurusan kesihatan pokok palma yang lebih baik.
Kata kunci: Penyakit, Livistona chinensis, Cycas revoluta, Ganoderma, taraf kesihatan pokok,
pengurusan penyakit.
1
1.0 Introduction
Urban forestry has been regarded as an important urban infrastructure to help reduce stress
from the results of artificial covers and to furnish and decorate a broad range for
environmental benefits (Grey & Deneke, 1986; Miller, 1997). Ornamental plant settings play
an important role in human life. They provide shade and beauty around homes, schools,
markets and shopping areas, places of work, along streets and highways, in city parks and
other areas. They also help to conserve energy and the quality of air, water and soil.
(Schroeder & Cannon, 1983; Ulrich, 1985; Heisler, 1986). Many types of ornamental species
are classified as urban plant for landscaping purposes either they are flowering plants or non-
flowering plants.
Ornamental plant may be susceptible to diseases due to several factors. For example,
the unfavorable surrounding climate, insects attack, poor drainage system and also lacks of
maintenance activities. In order to maintain the aesthetical value of these ornamental plants, a
study to identify the health status and types of diseases associated with the ornamental plant
should be conducted. Once the types of diseases is identified, the factors contribute to the
diseases can be overcome and the problems associated with ornamental plant can be reduced.
1.1 Problem Statement
Palm planted as urban tree are prone to pest and diseases. Two species of urban palm planted
in UNIMAS are Chinese Palm and Cycad Palm. It is of interest to identify the types of
diseases associated with Chinese Palm and Cycad Palm.
2
1.2 Objectives
The objective of this study is to assess the health status and to identify the types of diseases
associated with Chinese Palm and Cycad Palm in UNIMAS.
2.0 Literature Review
2.1 Urban Forest
Urban forest can be viewed as a “living technology”, an essential component of urban
infrastructure that helps maintaining a healthy environment for urban dwellers (Dwyer et al.,
1992). Urban forest is a land surrounded by human intensive area, ranging from small
communities to dense urban center occupied by trees and associated natural resources. Urban
forests can strongly influence the physical and biological environment (Dwyer et al., 1992).
2.2 Ornamental Plants
Ornamental plants are essential for enriching the appearance of any landscaping areas. An
ornamental plant is use as part of the landscape for purely aesthetic values (FAO, 1979). In
order to create a landscaping area with high aesthetical value, it is best for a professional
landscaper to include an even mix of various types of plants, trees, shrubs and flowers.
Ornamental trees, shrubs and other plants exist in a landscape area setting provide an
aesthetical environment. However, many ornamental plants require special maintenance in
order to prevent or control any diseases (FAO, 1979).
3
2.3 Benefits of Ornamental Plant
Ornamental plants provide a basic contact with nature and increase the pleasure in human
surroundings (FAO, 1979). Their value is difficult to quantify in economic terms but some of
the aesthetic benefits they can provide are create an aesthetical environment, intriguing
sounds, improving the air quality and also as a cooling shade (FAO, 1979).
2.3.1 Aesthetical Value
Ornamental plants increase the aesthetical value and life quality of an urban land area. The
presence of ornamental plant provides communities with pleasant environment for a place to
live, work, recreation, tourism and spending leisure time (Dwyer et al., 1992). Ornamental
plants also contribute significant increase in the tourism and recreational activities by
attracting more visitors to the country and increase the economic level (Dwyer et al., 1992). A
study in the eastern United States indicated that ornamental plant had increased the appraised
value of undeveloped land by 27% and that of 0.2 ha residential lots with houses by 7% (FAO,
1979).
2.3.2 Noise Reduction
Properly planting designs of ornamental trees and shrubs in urban area is significantly reduces
noise as stated in research conducted by Dwyer et al. (1992). The combinations of tall dense
ornamental trees with ground surface covers apparently reduce loudness by more than 50% of
noise (Dwyer et al., 1992). Ornamental plant will help in reducing noise pollution in urbanized
areas.
4
2.3.3 Air Quality Improvement
Ornamental plant can helps in improving and maintaining air quality by trapping the carbon
dioxide release to the atmosphere and convert it as food by the process of photosynthesis,
resulting in the releasing of oxygen gas which is an essential needs for human (Dwyer et al.,
1992). Ornamental plant also help in capturing gaseous pollutants such as carbon monoxide,
sulfur dioxide and ozone gaseous which is harmful to human (Dwyer et al., 1992).
2.3.4 Shading and Cooling
Ornamental plants have a considerable effect on the microclimate of urban areas with heavy
human population. They absorb heat as they transpirate, provide shade that reduces the solar
radiation and reflection, they can reduce or increase the wind speed and they can increase fog
precipitation and snow deposition (FAO, 1979). Ornamental plants have a significant
beneficial effect on the cost of winter heating and summer cooling of buildings. They break up
urban “heat islands” by providing shade. It had been estimated that the shade provided by
strategically placed of ornamental plant near a residential home can reduce air conditioning
costs by 30-50% and ornamental trees planted as windbreaks around buildings can reduce
winter heating energy costs by 4-22% (FAO, 1979).
5
2.4 Palm
Palm species are often thought as a symbol of tropics, but they also can grow well in warm
and temperate climates (Broschat, 2005). Palms present with bold-textured foliage and growth
characteristic forms that cannot be provided by other plants. They may have feather-like
leaves (pinnate) or fan-shaped leaves (palmate) on slender to thick trunks either single or
multi-stemmed (clumping) and range in height from a couple of feet to more than 100 feet.
There are several factors that need to be considered in choosing palm species for
ornamental purpose. Landscaping manager must consider the height and spread of the palm
species to be planted at a particular site. Tall palm should not be planted at site with overhead
power lines or large leaves or broad spread palm species is not suitable to be planted and
accommodate a very small space area (Broschat, 2005).
The maintaining activity of palm is fairly simple. That is why palm is chosen as one of
the most common ornamental plant. Completely dead leaves need to be removed if they do
not fall off by themselves and after a year of establishment, most palms do not require
supplemental irrigation except under severe drought conditions (Broschat, 2005). In this
study, two palm species of Chinese Palm and Cycad Palm were chosen.
6
2.4.1 Livistona chinensis
Common name : Chinese Palm
Family : Arecaceae
Origin : Australia, Malaysia, New Guinea, and Asia.
Livistona chinensis is a single stemmed fan palm. It is cultivated worldwide and usually found
in tropical and temperate climates (Loope et al., 2013). It is also known as Fountain Palm
(Jones, 1995; Wagner et al., 1999). It has up to 15 m tall trunk, pale green numerous leaves up
to 1.5 m long. The tips are pendulous and petioles armed with stout prickles. This attractive
palm with drooping fanned leaves makes it popular palm for ornamental purposes. It is
cultivated either as an avenue tree, single specimen or planted in groves. It is a hardy species
which survive in temperate and tropical climates. It can tolerate shady spots and young
Chinese Palm is good for indoor container plant. It may be susceptible to diseases of lethal
yellowing of palm (Dehgan, 1998).
Plate 1: Chinese Palm planted at CTF2, UNIMAS.
7
2.4.2 Cycas revoluta
Common name : Cycad Palm
Family : Cycadaceae
Origin : Malaysia, Taiwan, Japan and Pacific Islands.
Cycas revoluta is symmetrical plant with very low trunk. This small palm is about 1.5m height
and can grow up to 3m. This palm bearing long and pointed leaflets is a very slow growing
plant with shiny, thick and dark green leaves crown. The long narrow leaflets are strongly
recurved with revolute edges. Cycad Palm is tolerant to low temperatures. It needs sandy and
well-drained soil for successful growth. It is drought-tolerant, can grow in both under the sun
or shade and extremely poisonous to animals and human if ingested.
Plate 2: Cycad Palm planted near the lake of UNIMAS.
8
2.5 Common Urban Plant Diseases
Palm species have higher probability to be infected with many types of diseases. The common
urban plant diseases were root rots, crown rots and damping off, powdery mildew, fungal leaf
spots, leaf rusts, leaf and flower galls, botrytis blight, seiridium canker, bacterial disease, fire
blight and viral disease (Martinez & Williams, 2012). It was stated that in order for the
diseases to occur on a particular plant, three important factors must be present at the same
time; a plant must be susceptible to the diseases, the diseases-causing agent (pathogen) must
be present and able to infect the plant, and the environment must be favorable for diseases
development (Martinez & Williams, 2012). The research also provided several landscape
managements; keep disease out, keep landscape site clean, keep foliage dry and conduct
cultural, biological and chemical control (Martinez & Williams, 2012).
2.5.1 Ganoderma zonatum
Many researches have been conducted on diseases of urban plant. Palm is always related to
the diseases affected by Ganoderma zonatum (Price, 2000). In many cases, mature palms acts
as primary host of G. zonatum (Price, 2000). Research was conducted on butt rot of palm by
physical identification based on the symptoms appeared by the Ganoderma conk formation
(Price, 2000). The examples of palm species affected by Ganoderma are Elaeis guineensis
(Oil Palm), Cocos nucifera (Coconut Palm) and also Areca catechu (Betel Nut Palm)
(Sankaran et al., 2005). It was found that G. zonatum is a lethal fungal-disease where the
infected palm found in all situations and environment. The symptom of G. zonatum is the
wilting of older leaves and the light green or yellowish color of new leaves. Positive
conformation of this G. zonatum is by the formation of conks at the trunk. It was also noted
that this diseases had no labeled pesticide and spreads from spores of conks of infected palm
9
(Price, 2000). The ways to control this disease is by removing and incinerating of infected
conks and infected portions along with the stump and root. Wetting of palm base and
mounding mulch next to the trunk is avoided and soil fumigation helps to remove the spores.
2.6 Main Factors Affecting the Health Status of Urban Plant
There are many factors that prevents palm from established a healthy status and maintain its
aesthetical value as an urban plant. For example, the unfavorable weather and climate change,
nutrient deficiencies, lack of maintaining activities by landscaping manager and also pest
attack.
2.6.1 Climate Change
Urban plant usually expose to various types of environmental conditions. They may be hard
enough to withstand and overcome the climatic change. Weaker species which cannot survive
in the harsh environment will be susceptible and easily infected by many types of diseases.
Research on pest and diseases threatening urban plant under a changing climate found that
climatic change altered the patterns of disturbance from pathogens and herbivorous insects
through; physiological changes in the host plant, direct effects on the development and
survival of the pests and pathogens, indirectly through impacts on natural enemies, compet-
itors and vectors, and enhancing the suitability of the climate for non-native pests and
pathogens (Tubby & Webber, 2010).
10
2.6.2 Nutrient Deficiencies
Some diseases infected plants are not directly caused by fungal infection, but they may also
due to the nutrient deficiencies in the plant itself. A study was conducted on nutrients
deficiencies of urban and field-grown palms by running a physical appearance diagnosis on
different species of palm by Broschat (2005). It is found that urban palms are subjected to
numbers of potentially nutritional deficiencies; nitrogen, potassium, magnesium, iron,
manganese and boron (Broschat, 2005).
The study also stated that most palm nutrient deficiencies can be diagnosed using
visual symptom alone and the leaf analysis would be helpful in confirming the diagnosis by
selecting four to six pieces of central leaflets of youngest fully-expanded leaves (Broschat,
2005).
Nutrient deficiencies symptoms were tabulated in Table 1. The trunk condition, the
color of the leaves, the shapes of the leaves, health condition of the whole stand palm, the
appearance of any irregular structure or any symptoms of disease from the list were observed
and recorded. Some of these physical appearances can directly identify the disease associated
with the specific infected palm.
11
Table 1: The Symptoms of Nutrients Deficiencies of Palm Species (Broschat, 2005).
Types of Nutrient Deficiencies Symptoms
Nitrogen, N
Appear first on oldest leaves.
Uniform light-green color.
Entire palm canopy become chlorotic.
Leaf size becomes smaller.
Tapering of trunks.
Growth rate reduced sharply.
Potassium, K
Appear first on oldest leaves.
Older leaflets mottled with yellowish spot.
Necrosis is not marginal, but confined largely to tips of
leaflets.
Premature senescene of older palm leaves.
Magnesium, Mg
Appear first on oldest leaves.
Broad chlorotic bands along margin.
Central portions of leaves remaining distinctly green.
Results of improper fertilization.
Manganese, Mn
Appear on younger leaves.
Emerge chlorotic with longitudinal necrotic streaks.
Curling of leaves about rachis (frizzled appearance).
Iron, Fe
Appear on younger leaves.
Interveinal or uniform chlorosis.
Older leaves remain green.
Severe cases, new leaflets with necrotic tips, stunted
growth, dying of meristem or bud.
Boron, B
Appear on newly emerging leaves and remain until
mature.
Transverse translucent streaking on leaflets.
Sharply bent leaflets tips (hookleaf).
Bent tips are rigid and cannot be straightened out.
Weak, narrow leaflets towards tips of newly leaves;
drop-off leaflets leaving rachis tips devoid of leaflets.
Cause necrosis on primordial spear leaf; appearance of
blunt, triangular truncation of leaf tip.
Failure of newly emerging spear leaves to open
normally; tightly fused.
Severe cases: entire crown bend in one direction, newly
leaves growing downward along the trunk.
Common in deserts and seasonally dry areas.
12
2.6.3 Biotic Factors
Diseases also occur due to fungal and bacterial attacks besides of climate change and nutrient
deficiencies. The diseases and symptoms of infections caused by fungal and bacterial attacks
are tabulated in Table 2. Fungi are eukaryotic, spore-bearing, heterotrophic organisms that
produce extracellular enzymes and absorb the nutrition of plant (Jacobs, 2001). The ecological
characteristics of fungi are they have thallus, hyphae a cellular unit in filamentous fungi either
septate or aseptate and the bunch of hyphae forming mycelium. Fungi will absorb nutrient
form the host plant by various way such as heterotrophic, absorptive, produce extracellular
enzymes, saprobes; pathogens; symbionts (parasites - commensals - mutualists) (Jacobs,
2001). Fungi are separated into many several major phyla. They are Chytridiomycota,
Zygomycota, Basidiomycota, Ascomycota, Glomeromycota and Dikaryomycota (Jacobs,
2001).
Table 2: The Symptoms of Fungal and Bacterial Infection of Urban Tree (Jacobs, 2001).
Disease Symptoms
Phymatotrichopsis
Root Rot
(Phymatotrichopsis
omnivora)
Woody, dicotyledonous and perennial plants.
Sudden wilt during high temperature.
The roots are rotted and brown in color.
Mycelia strands produced by the fungus on the surface of
cortical tissue from decayed roots.
Phytophora Diseases
(Phytophthora
parasitica)
Herbaceous annuals to woody perennials.
Phytophthora bud rots of palms caused by P. parasitica.
Leaf and shoot blights, flower, fruit and bud rots, crown rots,
stem and trunk cankers of woody and herbaceous plants,
seedling damping-off, necrosis of feeder roots and collar and
root rots.
13
Pythium Diseases
(Pythium
aphanidermatum)
Seedling diseases of bedding and ornamental plants.
Seeds or seedlings rot before or after their emergence.
Post emergence damping off occurs several weeks after
emergence.
Seedlings become less susceptible with increasing age.
Rhizoctonia Diseases
(Rhizoctonia solani)
Soil borne fungus of agricultural crops; cotton, potatoes, lettuce,
vegetables and field crops.
Primarily seed decay, pre- and postemergence damping off
seedlings, bulb rots, root rots, crown blights, neck rots and
lower stem rots.
Fungus grows as weblike mycelium on the moist soil surface
and in the lesions. Mycelia growth easily visible with hand lens.
Most infections occur at or just below the soil surface. Infected
seedlings wilt and die.
Powdery Mildew
(Erysiphe
cichoracearum)
Primarily affect leaves, green stems, flower buds, and immature
fruit.
Obligate parasite, reproduce on living host tissue, not
saprophytically.
Whitish, powdery covering over infected leaves, stems, and
other aerial plant parts.
Leaves often curled or twisted. Severe leaf; leaf yellowing,
reduced leaf size and defoliation.
Fungus easily identified under the microscope by conidial
(asexual stage) and the sexual fruiting body (cleistothecium).
Rust Diseases
(Puccinia antirrhini, P.
lvacearum, Cronartium
arizonicum)
Symptoms are diverse as the fungi that cause the diseases.
Rust fungi attack leaves, infect flowers, fruit, and stems and
branches and trunks of woody flowering plants and conifers.
Most rust infections become locally systemic in host tissue
cause galls, blisters, and cankers in woody tissue.
Cytospora Canker
(Cytospora palmarum)
Affect fruit trees, hardwood, forest and shade trees, shrubs and
conifers. Infections on above ground woody tissue that has been
damaged by frost, fire, sunburn, wounds; pruning, broken twigs
and branches.
Sunken lesions on infected tissue, slowly invades and girdles
limbs or trunks result is a dead limb above the infection site.
Sooty Canker (Limb
Wilt)
(Hendersonula
toruloidea)
Invades only sunburned bark or area that was injured; pruning
wounds on smooth or thin barked deciduous trees. Fungus not
infects uninjured host tissue.
Sooty canker is the sooty, black canker develops beneath bark
tissue; presence of masses of black, fungal spores that appear
under the bark and on the surface of the canker.