DISEASES & PESTS OF MULBERRY FOOD PLANTS

FOLIAR DISEASES

1. Leaf Spot

Pathogen : Cercospora moricola

Occurrence : It is more prevalent during rainy season followed by winter. The disease starts progressing 35-40 days after pruning (DAP)/leaf harvesting and becomes severe on the 70th DAP.

Crop loss : 10-12 %

Symptoms : Brownish necrotic, irregular spots appear on the leaf surface. Spots enlarge, extend and join together leaving characteristic ‘shot hole’. Leaves become yellow and wither off as disease becomes severe.

silks
Leaf spot

Factors responsible for spreading of the disease:

Control measures to be adopted:

2. Powdery Mildew

Pathogen : Phyllactinia corylea

Occurrence : Disease is prevalent during winter and rainy seasons and progresses 40th DAP/leaf harvest becoming severe on 70th DAP.

Crop loss : 5-10%

Symptoms : White powdery patches appear on the lower surface of the leaves. The corresponding portions on the upper surface develop chlorotic lesions. When severe, the white powdery patches turn to brownish-black; the leaves become yellow, coarse and loose their nutritive value.

silks
Powdery mildew

Factors responsible for spreading of the disease:

Control measures to be adopted:  

3. Leaf Rust

Pathogen : Cerotelium fici

Occurrence : The disease is more prevalent during winter and rainy seasons. It starts progressing 45-50 DAP becoming severe on 70th DAP. The mature leaves are more prone to the disease

Crop loss :  10-15%

Symptoms : Initially, circular pinhead sized brown eruptive lesions appear on the leaves and later leaves become yellow and wither off.

silks

Leaf rust

Factors responsible for spreading of the disease:

Control measures to be adopted: 

4. Sooty mould

Pathogen : A group of fungi

Occurrence: The disease is more prevalent during winter (August-December) season.

Crop loss:  10-15%

Symptoms : Thick black coating develops on the upper surface of the leaves.

Factors responsible for spreading of the disease:

Control measures to be adopted: 

II. ROOT DISEASES

1. Root knot

Causal organism: Meloidogyne incognita (Nematode)

Occurrence: The disease is out break through out the year and more common in sandy soils under irrigated conditions.

Crop loss: 20 %

Symptoms:

silks silks
Root knot nematode disease

Factors for spreading the disease

Control measure:

2. Root rot

Causal organism : Rhizoctonia bataticola (= Macrophomina phaseolina)

Associated secondary microbes : Fusarium solani/ F. oxysporum/ Botryodiplodia theobromae

Occurrence: Throughout the year in all types of soils especially when the soil moisture and organic matter in soil are low.

Crop loss: 15 % and above depending on the soil health and climate.

Symptoms: Initially the above ground symptom of the disease appears sudden withering of plants and leaves fall off from the bottom of the branches and progressing upwards.

silks silks silks

Above ground symptoms of root rot (yellowing/withering of leaves)

silks silks silks
Below ground symptoms of root rot (rotting of the roots)

Factors for spreading the disease:

Control measure: A target specific new formulation “Navinya” (herbal 80% & chemicals 20%) is used for the control of root rot disease of mulberry

Method of application : Prune off the dried shoots above 15-30 cm from ground. Make shallow ring around stump and apply the Navinya solution made by adding 10 g of Navinya in 1 liter of water (i.e. 1 kg Navinya in 100 liter water; sufficient for 100 plants @ 1 liter/plant). Pour the solution over the pruned stump to drench completely. Cover with soil around the stump to prevent exposure to sunlight. Treat the surrounding mulberry plants also to prevent spreading of the disease.

Precautions to be taken:

III. PESTS

1. Pink Mealy bug

Occurrence & Symptom : Pink mealybug, Maconellicoccus hirsutus (Green) causes deformity symptom in mulberry which is popularly called as Tukra. Leaves become dark green, wrinkled & thickened with shortened inter nodal distance resulting in bunchy top appearance/resetting of leaves. It occurs throughout the year, but severe during summer months. Mulberry leaf yield is reduced by 4,500 kg/ha/yr due to this pest.

Control measures

Mechanical control:

silks silks silks

Clip off the infested portion by secateur, collect in a polythene bag and destroy by burning. This will help in reducing the chances of recurrence of pest. This practice may be followed when the silkworms attain 4th age.

Chemical control: Spray 0.2% DDVP 76% EC (@ 2.63 ml/lit water) 15–20 days after pruning. Safety period: 15 days.

Biological control:

Release predatory lady bird beetles Cryptolaemus montrouzieri @ 250 adult beetles or Scymnus coccivora @ 500 adult beetles in two equal splits at an interval of 6 months.

silks silks 

Availability of predatory lady bird beetles: Pest Management Lab., CSR&TI, Mysore (ph. No.0821-2903285) cost: Rs 120 per unit.

2. Papaya mealy bug
silks silks silks

Occurrence & Symptom: The papaya mealy bug, Paracoccus marginatus is an exotic pest which infest a variety of crops such as papaya, guava, teak, vegetables, Jatropha, and weed plants like Parthenium, Sida, Abutilon etc. In mulberry its infestation causes malformation of affected portion, stunted growth of leaf, presence of red/black ants, honey dew secretion, growth of sooty mould, and outright killing of the plant. At present occurrence of papaya mealy bug is sporadic.

CLASSICAL BIOLOGICAL CONTROL OF PAPAYA MEALYBUG
silks silks

Note: Exotic parasitoids are available at National Bureau of Agriculturally Important Insects (NBAII), ICAR, Bangalore [opp: CBI, Ganganagar, Bangalore; phone no. 080-23511982/98]

3. Mulberry Leaf roller
silks silks silks silks

Occurrence & Symptom : Incidence of Leaf roller, Diaphania pulverulentalis in mulberry starts with the onset of monsoon. It occurs from June to February but reaches peak during September – October months. The larva binds mulberry leaf blades by silken thread, stay inside & feed. Its feacal matter can be seen below the infested portion.

Control measures

Mechanical control: Remove the infested portion (along with the larva) by secateur, collect in a polythene bag and destroy by burning.

Chemical control:

Biological control : Release Trichogramma chilonis  egg parasitoid @ 1 Tricho card/week (for 4 weeks). Do not spray any insecticide after the release of trichogramma parasitoids.

(Note: Tricho cards are available on cost basis at Krishi Vigyan Kendra, Suttur, Nanjangud taluk, Mysore dist. or Parasite Breeding Lab., Dept. of Agriculture, [Near DC Office] Mandya)

4. Bihar Hairy Caterpillar

Occurrence & Symptom : Incidence of Bihar hairy caterpillar, Spilarctia obliqua in mulberry starts with the onset of monsoon. It occurs throughout the year and in certain pockets it appears sporadically. Young larvae are gregariously found feeding on the underside of leaf giving an appearance of mesh and one can make out from distance. Grown up ones are solitary, very active, spread throughout the field and feed voraciously on the foliage.

Control measures

Mechanical/Physical control: Collect the egg masses or gregarious young caterpillars and destroy by dipping in 0.5% soap solution or by burning.

Chemical control:

silks silks  

Biological control: Release egg parasitoids Trichogramma chilonis   @ 1 Tricho card/week for 4 weeks. Do not spray any insecticide after the release of trichogramma parasitoids.

silks silks silks
5. Thrips
silks silks  

Occurrence & Symptom : Thrips, Pseudodendrothrips mori, is a major pest in Tamil Nadu and minor pest in Karnataka & Andhra Pradesh. It occurs throughout the year and severe during summer (February - April). Both adults and nymphs lacerate the leaf tissues and suck the oozing sap. Affected leaves show streaks in early stages and yellowish/brown blotches in the advanced stage of attack.

Control measures

Mechanical/Physical control : Use sprinkler irrigation to disturb thrips population & eggs on the underside of mulberry leaves.

silks silks  

Chemical control: Spray 0.1% Rogor (@ 3 ml/lit water) 15 days after pruning. Safety period: 20 days.

Biological control: Release predatory lady bird beetles (Scymnus coccivora @ 500/acre).

6. White fly
silks silks silks

The name white fly is derived from the whiter appearance of the adults and their tendency to fly when disturbed. Adults have a pair of floury wings which are usually white with a few veins. In the recent years outbreak of Dialeuropora decempuncta has occurred on mulberry in southern state of Kerala and now observed to severely infest mulberry in the irrigated belt of Karnataka covering Mysore and Mandya districts.

Occurrence & Symptom : The spiraling of waxy material is the typical symptom of white fly attack. Prolonged dry spell followed by the hot humid weather favours the white fly flare up. Occur during the months March-June; October-December. Both nymphs and adults pierce and suck the sap from foliage and the damaged leaf become unfit for silkworm rearing.

Control measures

Mechanical/Physical control:

Chemical control: Spray 0.076% DDVP (@ 1 ml/lit water) 12 days after pruning (safety period: 10 days) and second spray with 0.05% Rogor 30% EC @ 1.5 ml/lit (safety period: 20 days)

Biological control : Release predatory lady bird beetles Cryptolaemus montrouzieri @ 250 adult beetles or Scymnus coccivora @ 500 adult beetles/acre.

Source:

Central Sericulture Research & Training Institute, Mysore, Karnataka

Diseases and pests of eri food plants

Diseases and pests of castor

Seedling blight

Symptoms
Management
silks

Alternaria leaf blight

Symptoms
.
Stage of attack:

Seedling to maturity.

Management

Wilt

Symptoms
silks
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
Red hairy caterpillar
Semi-looper
silks
Tobacco caterpillar
Hairy caterpillar
silks
Capsule borer
Jassids
White fly
silks
Diseases and pests of kesseru
silks
Source