Diseases Of Pulses

I. DISEASES OF REDGRAM

1. Wilt

Causal organism : Fusarium oxysporum f.sp.udum

Symptoms: The infected plants show gradual wilting and drying.Yellowing and premature drying of leaves and stems are noticed. The basal portion of stem and root region becomes black. When the bark of infected root is peeled, black streaks are seen and vascular tissues show discoloration. Xylem vessel is occupied by the growth of the hyphaewhich prevent the uptake of nutrients and water resulting in the death of plant.

Favorable conditions : Soil temperature of 17-25˚C; Continuous cultivation of red gram in the same field.

2. Powdery mildew

Causal organism: Leveillula taurica

Symptoms: On the lower surface of leaf, white powdery growth is seen in patches. Corresponding areas on the upper surface become yellow. This leads to premature shedding of leaves. Dry humid weather following rainfall favors the disease.

3. Leaf spot

Causal organism: Cercospora indica

Symptoms: Leaves show light brown small spots. Shot holes are formed in due course. Lesions develop on petioles and stem.

4. Sterility mosaic

Causal organism : Pigeon pea sterility mosaic virus

Symptoms:The affected plants are stunted and the inter nodes are shortened. Axillary buds are stimulated to grow and the branches are crowded at the top. The plant gives a bushy appearance. Leaves become small and crinkled exhibiting mottling symptom.The Eriophid miteAceria cajani transmits the disease.

Disease Management:

1.Seed treatment

Talc formulation of Trichoderma viride @ 4g or P. fluorescens @ 10 g/kg seed (or) Carbendazim 2 g/kg or Thiram @ 4 g/kg.

2.Wilt P. fluorescens (or) T. viride – 2.5 kg / ha + 50 kg of well decomposed FYM or sand at 30 days after sowing

3.Root rot : Spot drenching with Carbendazim @ 1 gm/ lit

4.Sterility Mosaic : Rogue out the infected plants in the early stages of growth. Spray Fenazaquin @ 1 ml/lit on 45 and 60 DAS as prophylactic spray