This document discusses common pests and diseases that affect rubber trees. It outlines several categories of diseases including leaf diseases, stem diseases, panel diseases, and root diseases. Some key leaf diseases mentioned are Colletotrichum secondary leaf fall and Oidium secondary leaf fall. Important stem diseases include bark necrosis, ustulina stem disease, and pink disease. The document also covers common pests such as termites, slugs and snails, mites, mealybugs, and scale insects. It provides details on symptoms and control methods for many of the major diseases and pests that can impact rubber production and economics.

1. COMMON PESTS & DISEASES
OF
RUBBER
GROUP : E

2.  Rubber - Hevea brasiliensis
 the important plantation crops in srilanka.
 The rubber tree is affected by a number of diseases
of economic important and they can be divided for
convenience into four categories.
 As well as pest attack also harmful to rubber plant.

3. IMPACT OF PESTS AND DISEASES
TO THE TREE
 Damage and defoliate leaves
 Cause the tapping panel and affect bark renewal
 Kill branches and trees
 Root and stem dieback

4. TO THE ECONOMICS
Lengthen the immaturity
period
Reduce latex yield
Increase cost of production
Affect the environment

5. LEAF DISEASES
 Collectotrichum secondary leaf fall
 Oidium secondary leaf fall
 Bird’s eye spot
 Crynecoccum leaf disease
 Fusicoccum leaf disease
 Cylindrocladium leaf disease

6. Oidium secondary leaf fall
• Fungus – oidium heveae (powdery mildew)
• Infects mostly to young shoots that refoliate after wintering
• Sign of attack is presence of numerous leaflets on the ground.
• Symptoms – leaf defoliation
young leaves cover with powdery masses
• Effect -reduces latex yield

7. Colletotrichum secondary leaf fall
Cause – fungus colletotrichum gloesporiode
Disease can occur leaves and green parts of plants such as
fruits and twigs rubber
Factors influence to spread disease :
High moisture in the environment
Genetic factors

8. Symptoms
 On young leaves : blackish brown splotches in the leaf middle
leaf blade wrinkled
wet rot incidence in affected area
leaf fall
 On old leaves : brown splotches with halo
yellow leaf becomes rough surface
further attacks cause the patches to be perforate
 On young twigs : rot, dry and eventually die back.
Disease spread through “spores”.
Wind, dew or rain water move the spores.

9. Bird’s Eye Spot
• Causative Agent : Drechsiera heveae (Fetch) M.B. Ellis
• Occurrence : A hot weather disease serious & damage in the nursery
: Weaker plants & plants growing under exposed situations
• Symptoms : Small necrotic spots with dark/brown margin & pale centre
: Premature defoliation & Die back

10. Corynespora leaf fall
• Corynespora cassiicola has been found for the first
time in China on Hevea rubber tree.
• The most important leaf disease of rubber in Asia
• Caused by Fungus Corynespora cassiicola
• Role of cassiicolin, a host-selective toxin, in
pathogenicity of Corynespora cassiicola, causal agent
of a leaf fall disease of Hevea.
• Cameroon, India, Indonesia, Malaysia, Sri Lanka
and Vietnam

11. • Mainly confined to the nurseries and young immature plants
in main field
• Symptoms on leaves included fishbone necrosis and spots or
characteristic railway track symptoms.
• Infects young and old leaves.
• Causes leaf fall, shoot dieback.
• Increase immaturity period, reduces yield.
• Kills plants.

12. Control measures.
Technical methods (indirect preventive
methods)
 plant resistant clones.
 Improve the plant conditions (fertilization ,
sanitation,drainage,reduce the frequency of
tapping)
Chemical methods
 Use of fungicides.
 Dusting the leaves with sculpture thought the
refoliating season at 5 to 6 weekly round.
 Fogging with fungicide tridemorph such as
calixin 75 EC at 0.5 a.i/ha

13. STEM DISEASES
• Bark necrosis
• Ustulina stem disease
• Pink disease

14. DRY ROT (Ustulina Stem Rot)
 caused by Ustulina deusta.
 observed near the collar region, on the main trunk of even on the branches
during the rainy season.
 The symptom appears as exudation of latex. Later fruiting bodies of the fungus
appear as soft circular to irregular, grayish white ear lobe like structures which
later join together and became grey or black and brittle .
 The fungus penetrates the wood and spreads inside. As a result the wood
becomes soft and the trees breakdown.
 Black double lines formed by the fungus are seen inside the wood.
 The fungus penetrate the bark through wounds and cracks and hence the
disease incidence is more following heavy wind

15. BARK NECROSIS(BN)
The necrosis of the rubber tree is an affection of the stem.
 It is expressed by a deterioration of the cortical tissues on the level of which are located in the conducting latex
tissues.
starting right at the grafting point situated in the transition zone between the trunk and the roots, the collar.
It is leading to the cessation of latex production, showed differences in latex biochemical characteristics, attacks
the tree vascular tissues.
the rubber trees hit by necrosis have poorer than normal root development.
causative pathogen for BN has not found, but showed that BN is favored by a combination of various stresses
It results from the accumulation of climatic and human-induced stresses and physiological malfunctions in the
grafted trees.
Chemical and biological methods can use for control this disease.

16. PINK DISEASE
Causative Agent :- Corticium salmonicolor
Symptoms
Pink colour mycelial growth on bark surface with streaks on latex
oozing out from the lesions
More damaging for plants in the age group of 2 to 12 years
 Main seat of infection is usually the fork region
Rotting , Drying up and Cracking of the affected
bark.
 Sprout develop from below the affected portion.
Clonal Suseptibity:- PB 217 , PB 311
RRII 105
Control Measures
• Can Use Prophylactic treatment

17. PANEL DISEASES
 Black strips
 Mouldy rot
 Panel necrosis

18. • Phytophthra palmivora
• P. meadii
BLACK STRIPE DISEASE
•. Renewed bark region
•Small depression are formed due to localized rotting
•.During of bark which gets pressed to the wood
•When scraped vertical blank line running downward
into tapping bark & upward into the renew barked
•Reduce yield
•Renew bark highly uneven
•During the rainy
season

19. Ceratocystis fimbriata attacks the tapping panel
• Causing a pale-grey mould on the surface of the panel
and dark discoloration in the wood under the surface.
Affect-
•Commonly in high moisture and weedy conditions
especially on panels reaching the ground
Mouldy rot of rubber-

20. •Tapping is regularly done during rainy season
•Tapping panel should be disinfected at weekly intervals by
brushing.
Chemical control of panel diseases-
• Fungicides can be used to treat tapping panels
Appling fungicide in two method-
•„„Spraying of fungicides using hand held sprayers
• Painting with brush

21. ROOT DISEASES
1.White Root Disease
2.Red Root Disease
3.Brown Root Disease
4.Purple Root Disease

22. White Root Rot Disease
• Infective fungal organism: Rigidoporus lignosus
• Symptoms :
root infection, colonization within the taproot
& other parts of the root.
: foliage discoloration
: tree branches die back
: tree eventually dies

23.  Causative agent is Phellinus noxius
 That disease occurrence often in replanted area
 & sandy or light soils.
SYMPTOMS
• Growth retardation
• General yellowish discoloration of the foliage
• Honeycomb structrure on wood surface & inside wood
• A layer of soil/sand with brown spots
BROWN ROOT DISEASE

24. Purple Root Disease
The occurrence of purple root disease caused by Helicobasidium compactum is
reported for the first time on Hevea brasiliensis in India .
Infection on nursery plants ,
occasionally leading to their mortality.
Disease symptom.
Purple- colored fungal growth on the root surface.
Adventitious root formation.
The presence of distinct fruiting bodies girdling the collar region.

25. CONTROL OF ROOT DISEASES
• Pre planting correct land clear procedure.
• During planting S application & planting creeping legume as cover
plant.
• Immature rubber chemical control.
• Mature rubber isolation trench.
• Completely killed & dried root , prune off & burnt
• Dried plants should be uprooted & destroyed
• Apply fungicide by painting or drenching

26. PEST OF RUBBER
 Termites
 Slug and snails
 Mites
 Mealy bugs
 Scale insect
 Bark feeding caterpillar

27. TERMITES ATTACK
Damage by Coptotermes curvignathus
.Attack can be above ground level . The
infestation is usually internal and may occur
through the roots.

28. Symptoms
• Mainly occur in mature plant.
• It occur a early stage of growth.
• A layer of mud on the surface of trunk.
• The bark texture become fissured and rough
• Reduce the value of timber.
• Leaves are yellowing and wilting.
• At an advanced stage the leaves turn brown and fall off.
• Finally tree will die.
• The bark can be seen to be riddled with holes.

29. Prevention and control
• Cultural method
1. Mechanical injury to trees
2. Pruning
3. Thinning should be conducted at suitable periods
4. Minimized weeding
• Biological method
1. Use of entomophagous nematodes
2. Use entomopatogenic fungi
• Chemical method
-Use pesticides
• Use pheromones
• Cultivate resistance species

30. SLUG AND SNAIL ATTACK
• Slug and snail Randomly distributed in rubber cultivated area
• Main Symptoms are
 Feed on latex by lacerating the tender leaves and buds.
 Growth of affected buds is arrested and side shoots develop
giving a bunchy appearance.
 Slugs drink latex from the tapping cut and collecting cup also.
• Clonal Susceptibility: Nursery seedlings are more susceptible
• Control Measures: Broadcast 2.5% Metaldehyde bait pellets
(snail kill 2.5) at the base of the infested plants or seedling
beds
• Physical barriers: scatter crushed egg shells, sawdust or
wood shavings around plants at risk.

31. MITE ATTACK
Causative Agent: Hemitarsonemus dorsalis.
Occurrence: Sporadic incidence on young rubber plants in nurseries.
Symptoms: Not a serious pest. Minute organisms with four pairs of legs.
Suck sap from the leaves resulting in crinkling and shedding.
Clonal Susceptibility: Clones like PB 217,RRII 105 and RRIM 600 are
susceptible.
Control Measures: Dust sulphur or spray sulphur 0.2%(Sulfex 80 WP
2.5g/L)
Dicofol 0.05%(Kelthane 18 EC 3ml/L)

32. SCALE INSECTS ATTACK
• Scientific name - Coccoidea
• SCALES are limpet like insects that feed by sucking
sap from a rubber plants. Scale insect can weaken plants
and some excrete sticky substance (like honeydew ) on
foliage ,which allows the growth of black,sooty molds.
• CONTROL MEASURES - insects prune and dispose of
infected branches, twigs and leaves or hit product
protects against common insect attacks.