Diseases and Pests Management

Diseases and Pests of Food Plants

Diseases and pests of mulberry food plants

Powdery mildew

Causal organism: Phyllactinia corylea, fungus

Symptom

White powdery patches on the lower surface of leaves, gradually increased and cover the whole leaf surface.
Affected leaves turn yellowish and defoliate prematurely.
Peak season: October-November
Management: Foliar spray of 0.2% sulfex 80 WP (2g/l). Lower surface of the leaves should be thoroughly drenched.
Safe period: 15 days.

Leaf rust

Causal organism: Peridiopsora mori, fungus

Symptom

Several small pin head shaped brown postules appear on the lower surface of matured leaves.
Reddish brown spot appear on the upper surface of the infected leaves.
Severely infected leaves turn yellowish and margin of the leaves become dry.
Peak season: February-March
Management: Foliar spray of 0.2% Blitox 50 WP or 0.2% Bavistin 50 WP. Safe period: 15 days.

Leaf spot

Causal organism: Cercospora moricola, fungus

Symptom

Minor circular light brown spot appear on both sides of the leaves.
The adjacent spots unite together to form a larger spot.
The necrotic tissues of such spots drop out and form the characteristics "shot holes"
Highly infected leaves defoliate prematurely.

Peak season: Rainy and winter season.

Management

Avoid dense planting.
Collect and burn unused infected leaves after pruning.
Spray 0.1% Bavistin when disease symptom appears on 2-3 leaves at ten days interval.

Safe period: 7 days.

Sooty mould

Casual organism: A group of ascomycetes and deuteromycetes fungi
Symptom: Thick black coating developed on the upper surface of the leaves.
Peak season: August-December

Management

Spray 0.2% Indofil-M45 to check the growth of saprophytic fungi.
Foliar spray of 0.02% Monocrotophos on 15th and 30th day of pruning to control white fly infestation.

Safe period: 15 days.

Mealy bug (Maconellicoccus hirsutus)

Season of incidence: April-June.

Nature of damage

Nymphs suck the plant sap from the meristematic region of tender leaves which causes curling of leaves at growing tips. The infested leaves become dark green in colour and shorter, the plants become bushy at the top, stems thickened and twisted. These symptoms altogether is called as "TUKRA".

Economic Threshold Level (ETL): 10 bugs per shoot.

Management

Clip and burn the tukra infested shoots during initial stage of infestation.
Spray 0.1-0.2%Dimethoate
Release predator Pullus bourdillioni Kapoor @ 600 pairs/acre.

Safe period: 14 days.

White fly (Dialeuropora decempuncta)

Season of incidence: April-June and August-November.

Nature of damage

Maggots and adults suck the plant sap causing chlorosis, yellowing and curling of leaves. The honey dew secreted by the maggots serves as a medium for growth of sooty mould which in turn damage the mulberry plants during September-November.

Economic Threshold Level (ETL): 10 flies per shoot

Management

Keep the mulberry garden free from weeds.
Erect yellow trap made of polythene sheets (1.5 m x 1m) coated with sticky oil @ 40-50/ acre.
Spray 0.02%Monocrotophos / 0.1% Dichlorovos.
Release predator Coelophora unicolor for biological control of the pest.

Safe period: 15 days.

Thrips (Pseudodendrothrips mori Niwa)

Season of incidence: April-May and August-November.

Nature of damage

The infestation of thrips causes depletion of moisture and yellowing of leaves. The leaves become boat shaped in advanced stage of infestation and prematurely fall.

Economic Threshold Level (ETL): 20 insects per leaf.

Management

Keep the mulberry garden free from weeds.
Erect yellow trap made of polythene sheets (1.5 m x 1m) coated with sticky oil @ 40-50/ acre.
Spray 0.1-0.2% Dimethoate.
Release predator Micraspic discolor for biological control of the pest.

Safe period: 14 days.

Source

Package of practices of Muga, Eri and Mulberry Sericulture for North Eastern region of India, 2005, Central Muga Eri Research & Training Institute, Lahdoigarh, Jorhat, Assam.
Directory of Sericulture Technology 2008, Karnataka State Sericulture Research and Development Institute, Bangalore- 560 062.

Diseases and pests of muga food plants

Leaf Spot

Causal organism: Phyllosticta perseae

Symptoms

Appearance of circular or irregular brown spots surrounded by yellow margin on both surface of the young and matured leaves.
More prominent on the upper surface.
The first sign of the disease is appearance of slightly pale areas on upper surface of the leaves.
The lower leaf surface shows collapse of epidermis, which loses contact with mesophyll tissues.
As the disease progresses, the minute spots spread irregularly and become brown in colour, get collapsed and form larger patches causing drying up of entire lamina.
Excessive spotting and destruction of green tissues of the leaf leads to heavy reduction in leaf yield.

Peak Season: July with 12-22 PDI.

Management

Foliar spray of 1% Dithane-M45 twice in 15 days interval controls the disease up to 85%

Leaf Blight

Causal organism: Colletotrichum gloeosporioides Penz.
Causes 48-60% plant infection and 14-22% leaf area destruction.

Symptoms

Appearance of ash coloured, round to oval spots spread irregularly over the entire young as well as matured leaves.
As the disease progresses, the spots get collapsed and malformed.
Spots usually appear nearer to the leaf edges and infected area dries into brownish black colour.
With the disease severety, brownish coloured lesions/ streaks (stromatic masses or sclerotia) appear on the twigs of the plant. The entire branch or top of the branch may get withered.
Causes severe premature leaf fall.

Peak season: June- July.

Management

Pluck and burn the infected leaves.
Since the pathogen is soil born and remain viable under the soil surface, practice deep hoeing to destroy the pathogen inocula.
Cultural practices such as pruning and pollarding are effective in controlling the disease
Spray Indofil-M45 as a general protection measure.

Grey Blight

Causal organism: Pestalotiopsis desiminata (Thuem.) Stey.
It causes 48-60% plant infection and 22-28% leaf area destruction.

Symptoms

Appearance of small, oval brown grey lesions irregularly scattered on the leaves.
Symptoms appear both in young and matured leaves.
With the progress in disease infection, the spots get collapsed, malformed and ultimately the entire leaf dries up.

Peak season: May to August.

Management: Spray 0.1% Bavistin on leaves twice in 15 days interval.

Source

Package of practices of Muga, Eri and Mulberry Sericulture for North Eastern region of India, 2005, Central Muga Eri Research & Training Institute, Lahdoigarh, Jorhat, Assam.
Directory of Sericulture Technology 2008, Karnataka State Sericulture Research and Development Institute, Bangalore- 560 062.

Red Rust

Causel organism: Cephaleuros parasiticus Karst.
Causes 12-22% leaf damage in Som and 39% in Soalu.

Symptoms

Appearance of yellow green to orange or grey coloured hairy postules on the upper surface of the leaves.
The postules tend to elongate into the stems and petioles.
The affected branches become stunted and bear few leaves.

Peak season: May to August.

Management

Spray 1% Bordeaux mixture as general protective measure.
Timely utilization of leaves minimizes the spread of the disease.

Stem Borer (Zeuzera indica)

Silks Silks

Season of incidence: December- January
Nature of damage: The pest is found in both Som and Soalu plants and prevalent in entire north eastern region. The moths lay eggs on the bark of the tree and hatched larvae enter into the stem by making holes. The larvae feed on vascular tissues and pith. The life cycle takes nearly one year.
Extent of damage: Maximum infestation is 71% in Som and 73% in Soalu. The number of holes/ plant is 1 to 5 and size of the holes varies from 0.5 to 2.0 cm.

Management

Plug the borer holes with cotton swab soaked in 1.5% Nuvan solution followed by mud plastering. It controls up to 90% of infestation.
Spray Monocrotophos @ 0.05% in the infested portion.

Leaf gall

Pauropsylla beesoni in Soalu and Aspondylia sp in Som plants.

Nature of damage: Gall is malignant tumour like growth on the leaves induced by the toxin like saliva secreted by gall insects inside the leaf epidermis.

Extent of damage: Maximum infestation is 30% in Som and 49% in Soalu plants. Intensity of infestation is more in Soalu plants than Som. Size of the galls varies between 0.5 to 1.2 cm in diameter and number of galls/ leaf ranges between 20 to 90.

Management

Apply 0.03% Dimecron and 0.5% Rogor solution.
Pluck and burn the infested leaves.
Cultural practices like pruning, pollarding, weeding and deep hoeing are also effective in controlling the pests.

Shoot Borer

Season of incidence: September to November.

Nature of damage

It is common in Som and found in apical twigs of the plants. Side shoots are bored from the nodal portion through the axils and the main veins of the leaves. A tunnel is formed inside the main stem by the insect. Young plants die in severe cases of infestation.

Extent of damage: Maximum infestation of 70-80% occurs during September to November.

Management

Mechanical control is the only way to reduce the infestation by cutting/ clipping and burning the infested twigs.

Amphutukoni (Cricula trifenestrata Helf)

Season of incidence: June to September.
Extent of damage: 80-90% leaf loss.

Management

Collect and destroy the eggs.
Spray 0.5% Phosphomidon in 15 days interval.

Source

B.K. Singh, N. Tiken Singh, 2010, Muga Silkworm Seed Organization (MSSO), P-4 Unit, Mendipathar, East Garo Hills, Meghalaya.
Package of practices of Muga, Eri and Mulberry Sericulture for North Eastern region of India, 2005, Central Muga Eri Research & Training Institute, Lahdoigarh, Jorhat, Assam.
Directory of Sericulture Technology 2008, Karnataka State Sericulture Research and Development Institute, Bangalore- 560 062.

Diseases and pests of eri food plants

Diseases and pests of castor

Seedling blight

Symptoms

Young plants are affected.
Both the surfaces of leaf turn yellow or brown with concentric brown zones on lower surface of leaf.
Stems are also affected
Dull green round patch on cotyledons and spreads to the base.

Management

Seed treatment with Thiram or Capton @ 3 g/kg
Spray copper oxychoride @ 3 g/L.

Alternaria leaf blight

Symptoms

Light brown spots on cotyledons, turn angular with age.
Inflorescence and capsules develop sooty growth.
Immature capsule turn brown and fall. Affected capsules have small seeds without oil

Stage of attack: Seedling to maturity.

Management

Seeds should be treated with Thiram @ 3g/kg.
Spray 0.2% Mancozeb.

Wilt

Symptoms

Wilting of plants.
Root degeneration.
Dropping of leaves.
Necrosis of affected tissue and finally leading to death of plants.

Stage of attack: Seedling to maturity

Management: Seeds should be treated with 3g/kg Thiram or 2g/kg Carbendazim.

Cercospora leaf spot

Symptoms: Both surfaces of leaf bear black or brown spots with pale green margin. Finally turn brown and falls.
Stage of attack: Throughout the crop.
Management: Spray 0.3% Copper oxychloride or 0.25% Mancozeb for 2-3 times.

Powdery mildew

Symptoms: White powdery growth under the surface of the leaves. Stage of attack: November to March.
Management: Spray 0.2% sulphur at 15 days interval during dry weather.

Red hairy caterpillar

Nature of damage: Defoliation, more infestation in young crop. Peak season: June-August.
Management: Spray 0.05% Monocrotophos or 0.03% Fenvalerate or 0.05% Quinalphos or 0.02% Methyl Parathion.

Semi-looper

Nature of damage: Defoliation.
Peak Season: July-September.
Management: Spray 0.05% Monocrotophos or 0.07% Endosulphan.

Tobacco caterpillar

Nature of damage: Defoliation.
Peak Season: August-October.
Management: Spray 0.05% Chloropyriphos or 0.05% monocrotophos.

Hairy caterpillar

Nature of damage: Defoliation, bore the leaves and capsules.
Peak Season: October-December.
Management: Spray 0.05% Chloropyriphos or 0.05% monocrotophos.

Capsule borer

Nature of damage: Bores the capsule.
Peak Season: November-March
Management: Spray 0.05% monocrotophos or dust the spike with 1.5% quinolphos or 2% methyl parathion.

Jassids

Nature of damage: Sucks the sap from plants and hopper burn symptoms on severe infestation.
Peak Season: November-January.
Management: Spray 0.05% monocrotophos or 0.05% dimethoate.

White fly

Nature of damage: Crop gives weak appearance and sooty mould is developed on severe infestation.
Peak Season: February-March
Management: Spray 0.05% monocrotophos or 0.05% dimenthoate.

Diseases and pests of keseru

Details of disease and pest management in Kesseru is yet to be studied, since the plant is less susceptible to diseases and pests attack. However, attack of Termite is found in hilly areas. A beetle pest, which is nocturnal in habit, sometimes damages young leaves of Kesseru plants. To avoid pests and diseases, spray 0.1 % Rogor or 0.05% Dimecron or 0.07% Nuvan along with 0.1% Indofil-M45 @ 1000- 1200 l/ha 2-3 times at an interval of 10-15 days.

Source:

B.K. Singh, N. Tiken Singh, 2010, Muga Silkworm Seed Organization (MSSO), P-4 Unit, Mendipathar, East Garo Hills, Meghalaya.
Package of practices of Muga, Eri and Mulberry Sericulture for North Eastern region of India, 2005, Central Muga Eri Research & Training Institute, Lahdoigarh, Jorhat, Assam.
Directory of Sericulture Technology 2008, Karnataka State Sericulture Research and Development Institute, Bangalore- 560 062.