Cultivation of Green Gram (Moong Bean) in India

Pest

Symptom

Control

White Fly

The infested plants become very weak showing downward cupping of the leaves giving a sickly look and the plant may die Insect secretes honeydew on leaves resulting in the blackening of leaves, drastically reducing photosynthetic rate and drying of leaves. Whitefly is a vector of the number of viral diseases especially mungbean yellow mosaic virus (MYMV).

1)Seed treated with Dimethoate 30 EC @ 5ml/kg; 2) Foliar spray of Triazophos 40 EC @ 2.0 ml/l or Malathion 50 EC @ 2.0 ml/l at 10-15 days intervals if required; 3) Grow cotton as a trap crop one month earlier between the mungbean rows; 4) Grow maize, sorghum or pearl millet as a barrier crop to minimize the incidence of whiteflies; v) Install Sticky trap; 5) Opt. resistant varieties

Bean Thrips

The thrips nymphs and adults feed on stigma inside the flower, flower sheds before opening and there is elongation of the terminal shoot. Plants attain a bushy growth and the crop looks dark-green in color, bearing few pods with shriveled grains.

1) Seed treatment with Thiomethoxam 70 WS @ 2 ml /kg seed + foliar spray of Thiomethoxam 25 WG 0.2 g/liter of water of is quite effective in controlling bean thrips; 2) Spray neem seed kernel extract (50 g/l) and neem oil 3000 ppm @ 20 ml/l; 3) Opt for resistant varieties 4) The incidence of bean thrips can be minimized by intercropping mungbean with cotton;5) Spray of Triazophos 40 EC @ 2.0 ml/liter, Ethion 50 EC @ 2 ml/liter of water.

Stem Fly

Stem fly (Ophiomyia phaseoli) maggots mine the leaves or bore into the leaf petiole or tender stem resulting in withering, drooping, and death of the plant. The characteristic symptoms of damage include drooping of the first two leaves and yellowing of plants. It can cause 5 – 20% damage in mungbean.

Follow clean cultivation, crop rotation, earthing up, growing trap crop, destroying alternative hosts like Solanum nigrum to minimize the stem fly incidence; 2) Opt for resistant 3) Seed soaking either in imidacloprid 17.8 SL @ 5.0 ml/kg seed in 100 ml water for one hour or thiomethoxam 25 WG @ 5.0 g/kg seed in 100 ml water to avoid early incidence of stem fly is recommended; 4) Spray either Imidacloprid 17.8 SL @ 0.2ml/l or thiomethoxam 25 WG @ 0.3g/lit at 15 days after sowing

Bihar Hairy Caterpillar

Female moths lay eggs on plants in a field. The young caterpillar eats away all the green matter of the leaves and it can be easily recognized by perforated, dusty white colored leaves in the field. The grown-up caterpillars feed voraciously on leaves, soft stems, and branches. The insect totally denude the crop within a few days resulting in total failure of the crop.

1) Uproot the damaged plants along with the young larvae at the gregarious phase and burry under the soil; 2) Spray of Quinalphos 25 EC @ 2.5 ml/liter or Dichlorvos 10 EC @ 1.0 ml/ liter or Fenvalerate 20 EC @ 1.87 ml/ liter of water or dusting with Fenvalerate 0.4% @ 15 kg/ha.

Disease

Symptoms

control

Yellow Mosaic Disease

These are first visible in the form of yellow, diffused, round spots scattered on the leaf lamina. These spots expand rapidly and the leaves show yellow patches alternating with green colour of the leaves. The newly emerging leaves, after initial symptoms, show these symptoms right from the beginning. The affected leaves later turn completely yellow and get reduced in size.

1)Rogued out disease Plants

2) In order to prevent whitefly (Bemisia spp.) infestation spray with triazophos 40 EC @ 2.0 ml/l or malathion 50 EC @ 2.0 ml/l or oxydemeton methyl 25 EC @ 2.0 ml/l at 10-15 days intervals if required; 3) Grow tolerant/resistant varieties

Leaf Curl

The symptoms are visible first in third leaf after three to four weeks of sowing. These are characterized by the enlargement of leaves followed by their crinkling. Later the leaves become thicker and leathery. The affected plants, however, do not die till the harvest of the crop.

1) Treat the seeds with imidacloprid 70 WS@ 5ml/kg; 2) Foliar spray of insecticide (dimethoate 30 EC @ 1.7ml/ha) on 30 days after sowing; 3) Rogue out the infected plants and Field sanitation; 4) Use resistant varieties like

Cercospora Leaf Spot

 It is the most important fungal disease of moong crop. In the diseased condition, small round spots, violet red in colour may be observed. These spots can be recognised by their grey coloured centre. Such spots are also visible or pods and the affected pods become blackened.

1) Field sanitation, crop rotation, destruction of infected crop debris; 2) Opt for resistant varieties 3) Treat the seeds with thiram or captan @ 2.5g/kg of seed; 4) On appearance of the symptoms spray with carbendazim 50 WP @1.0 g/liter or mancoze 75 WP @ 2.0 g/liter or hexaconazole (contaf 5 % EC) @ 1 ml/ liter of water.Subsequent spray should be done after 10 to 15 days, if required. Spraying with copper oxychloride @ 3 to 4 g /liter water has also been found effective in management of the disease.

Anthracnose

The disease is initially characterized by the production of dark brown circular spots. Later the spots increase in size by developing concentric ridges. The areas in between the concentric ridges remain ash-colored. The infection may also spread to pods where dark colored spots are visible on them.

1) Hot water seed treatment at 58oC for 15 minutes is effective in checking the seed-borne infection and an increasing proportion of seed germination; 2) Treat seed  with carbendazim 50 WP @ 2g/kg of seed 3) Spray the crop with carbendazim @ 2g/ liter of water with the first appearance of symptoms on the crop and repeat after 15 days (if Needed).