TNAU Agritech Portal
  Home | About Us | Success Stories | Farmers Association | Farmers' Innovation | Publications | FAQs | Contact

Crop Protection :: Pests of Black and Green Gram

Crop: Green gram

Scientific name: Vigna radiata Family: Fabaceae

Crop: Black gram

Scientific name: Vigna mungo Family: Fabaceae

Important pests of Black and Green Gram

I. Borers

II. Sucking pests

III. Flower feeder

Major pests of black and green gram
I. Borers
1. Gram pod borer: Helicoverpa armigera
Symptoms of damage 
  • Defoliation in early stages
  • Larva’s head alone thrust inside the pods and the rest of the body hanging out.
  • Pods with round holes

Management

  • ETL: 10% of affected pods

Identification of the pest

Eggs – are spherical in shape and creamy white in colour, laid singly
Larva - shows colour variation from greenish to brown. Green with dark brown grey lines laterally on the body with lateral white lines and also has dark and pale bands.
Pupa – brown in colour, occurs in soil, leaf, pod and crop debris
Adult - light pale brownish yellow stout moth. Fore wing grey to pale brown with V shaped speck.Hind wings are pale smoky white with a broad blackish outer margin. 

 
2. Spotted pod borer: Maruca testulalis
DSCN5126
4

Symptoms of damage 

  • Defoliation in early stages
  • Larva’s head alone thrust inside the pods and the rest of the body hanging out.
  • Pods with round holes

Identification of the pest

  • Larva - Greenish white with brown head. It has two pairs of dark spots on the back of each segment
  • Adult - Forewings- light brown colour with white markings; Hindwings – white colour with brown markings at the lateral edge

Management

  • ETL: 3/plant
  • Phosalone 0.07%
    (Spray fluid 625 ml/ha)
    Note : When the activity of coccinellid predator (both grubs and adults) is seen, insecticide application should be avoided.
 
3. Spiny pod borer, Etiella zinckenella
Symptoms of damage 
  • Dropping of flowers and young pods
  • Older pods marked with a brown spot where a larvae has entered
Identification of the pest
  • Larval – greenish initially, turns pink before pupation.
  • It has 5 black spots on the prothorax

Adult

  • Brownish grey moth 
  • Prothorax – orange in colour
  • Fore wing - has a white stripe along the anterior margin
 
4. Blue butterfly: Lampides boeticus
http://farm1.static.flickr.com/96/250087030_ceb7546cf9.jpg?v=1176718923 Symptoms of damage 
  • Buds, flowers and young pods with boreholes
  • Presence of slug like caterpillar.
  • Honey dew secretion with black ant movements

Identification of the pest

  • Larva – It is flat and slightly rounded; Pale green with a rough skin.
  • Adult - moth is greyish blue with prominent black spots in the hind wings and a long tail; Ventral side of wings with numerous stripes and brown spots

 

Management

Spray any one of the following insectcides (Spray fluid 500 l/ha)

  • Emamectin benzoate 5%SG 220 g/ha
  • Indoxacarb 15.8%SC 333 ml/ha
  • NSKE 5% twice followed by triazophos 0.05%
  • Neem oil 2%
 
5. Grass blue butterfly: Euchrysops cnejus
572937371_1365cde7f1_m

Symptoms of damage

  • Buds, flowers and young pods with boreholes and presence of slug like caterpillar.
  • Larval entry hole on the pod is plugged with excreta.

Identification of the pest

  • Larva - pale green or yellow with a red line and short black hairs on the body.
  • Adult - butterfly is blue, medium sized with 5 black spots in the hind wings and two black spots in the inner margin.

 

Management of pod borer complex

  • ETL 10% affected parts
  • Deep summer ploughing in 2-3 years to eliminate quiescent pupa.
  • Early sowing, short duration varieties.
  • Avoid closer plant spacing.
  • Grow tall sorghum as comparison crop to serve as biological bird perches
  • Collect and destroy larvae and adults to the extent possible
  • Install pheromone traps at a distance of 50 m @ 5 traps/ha for each insect pest.
  • Install Bird perches @ 50/ha.
  • Setting of light traps (1 light trap/5 acre) to kill moth population.
  • Control is achieved by releasing of Trichogramma chlionis at weekly intervals @1.5 lakh/ha/ week for four times.
  • Conserve green lacewing, predatory stink bugs, spider, ants
  • Application of NPV 250 LE /ha with teepol 0.1% and Jaggery 0.5% thrice at 10 – 15 days interval commencing from flowering stage. (Note: Insecticide / Ha NPV spray should be applied when the larvae are in early stage).
  • Bt @ 600 g, neem oil/ pungum oil 80 EC @ 2ml/lit
  • Spray NSKE 5% twice followed by triazophos 0.05%.
  • Apply any one of insecticides at 25 kg/ha. quinalphos 4D, carbaryl 5D
  • Spray insecticides like Quinalphos 25 EC @ 1000 ml/ha.

 

II. Sucking pests
1. Bean Aphids: Aphis craccivora    

Symptoms of damage

  • Leaves, inflorescence stalk and young pods  covered with dark coloured aphids
  • Honey dew secretion with black ant movements

Identification of the pest

  • Nymphs and Adult – dark coloured with cornicles in the abdomen

Management

Spray any one of the following insectcides (Spray fluid 500 l/ha)

  • Emamectin benzoate 5%SG 220 g/ha
  • Indoxacarb 15.8%SC 333 ml/ha
  • NSKE 5% twice followed by triazophos 0.05%
  • Neem oil 2%
 
2. Leaf hopper -  Empoasca kerri

Symptoms of damage

  • Leave mottled and yellowish in colour
  • Green colour insects found under surface of leaves

Identification of the pest

  • Adult – elongate, active, wedge shape, green insects

Management: 

Spray the infested crop with methyl-o- demeton 750 ml in 700 - 1000 L water per hectare

 
3. Pod bugs:  Riptortus pedestris

Symptoms of damage

  • Pods with black spots
  • Shedding of green pods
  • Poorly filled pods with shriveled grains inside
Identification of the pest
Riptortus pedestris
  • Brownish black and hemispherical 
  • Nymphs – resemble dark brown ants

Management:

  • Dimethoate 30% EC 500ml/ha
  • Methyl demeton 25%EC 500ml/ha
  • Imidacloprid 17.8 SL 100-125 ml/ha
  • Thiamethoxam 25% WG 100 g/ha
 
4. Lab lab bug or Stink bug: Coptosoma cribraria

Symptoms of damage

  • Cluster on the  plant  parts and suck the sap

Identification of the pest

  • Nymphs and Adult - sub globular, oval and greenish shield bug.
  • It has a characteristic buggy odour

 
5. Whitefly – Bemisia tabaci

Symptoms of damage

  • Leave mottled and yellowish in colour
  • vector of yellow mosaic virus

Identification of the pest

  • Adults -are small, yellow bodied insects with white wings which are densely   covered with a waxy powder.
  • Nymphs and pupae -are black and round or oval. Pupae have marginal bristles
Management of sucking pests

Spray any one of the following (Spray fluid 250 l /ha)

  • Methyl demeton 25 EC 500 ml/ha
  • Dimethoate 30 EC 500 ml/ha
III. Flower feeder
6. Blister beetle: Mylabris phalerata

Symptoms of damage

  • The adult feeds voraciously on buds and flowers.

DSCN2474

Identification of the pest

  • Eggs - are light yellowish in colour and cylindrical in shape.
  • Larvae - Young grubs are white in colour.
  • Adult – Elytra are black in colour with a round orange spot and two transverse wavy   orange bands across the wings.

Management

  • Manual collection or collection with insect net and killing of adults in kerosenized water appears to be the only possible solution.


Home | About Us | Success Stories | Farmers Association | Publications | FAQs | Site Map | Disclaimer | Contact Us

© 2013 TNAU. All Rights Reserved.