1. Seed and seedling Diseases
Symptoms
- Sick Seed does not grow properly
- If the some seeds grow, the plant wilt and necrosis of plant occur.
- Wilting of newly grown plants occur mostly in the early growing crops.
Treatment
- Use of resistant varieties.
- Seed treatment with Toprin-M @ 2gm/kg of Seed.
i. Leaf Blight of Maize
Symptoms
- The Disease appears first on lower leaves and then spread on all the leaves.
- Brown oval shaped spots are produced which spread rapidly at 25-30C0.
- In Punjab, the disease attacks on the crop near maturity.
Treatment
- Spray the fungicide Dithan M-45 @ 500gm / acre or Benlate 500gm/acre.
- Destrray the plant disease debris of previous crops.
ii. Stalk Rot
Symptoms
- Plants start rottening from the 2nd internodes, leaves turn pale, dry up and plants fall on the ground.
- When infected stalks are split, the phloem appears dark brown and there is browning of tissues and pith is shredded off.
- Cobs droop down, grains of the cobs remain small which reduce production
Treatment
- Seed treatment with Toprin-M @ 2gm/kg of seed.
- Use of resistant varieties.
- Ridge sowing also reduces the diseases.
iii. Ear Rot
Symptoms
- Many fungi cause ear rot.
- Infected kernels develop a cottony growth.
- Sometimes light blue green or black powder grows between the kernels or on the cob surface.
Treatment
- Use of resistants varieties or hybrids.
- After harvesting of the crop, remaining parts of plants should be destroyed.
- Moisture %age should not more than 12% when cobs are stored in gowdams.
2. Pearl Millet / Bajra
i. Green Ear Disease of Bajra
Symptoms
- The diseased plant show the symptoms of stunting and malforonation (no grains) of floral parts.
- The ears remain small and twisted leaf like structures are produced in the ears which are green in color
- The glumes, stamens and pistils are replaced by leafy shoots and there is no formation of any grain.
- The diseased plants remain dwarf due to reduction of internodes.
Control
- Seed treatment with different fungicide e.g. Toprin-M @2gm/kg of seed or benlate @ 2gm/kg of seed.
- Use of resistant varieties.
ii. Sumt of Pearl Millet
Symptoms
- The disease attacks the plants from leaves to heads.
- Due to the attack of disease, the grains in the heads are converted into black powdery mass and the yield is affected badly.
Control
- Use resistant varieties
- Sow the seeds after treatment with feticide e.g. Toprin-M @ 2gm/kg of seed.
iii. Rust of Pearl Millet
Symptoms
- This disease attacks on the leaves of the plants.
- The disease spots can be easily seen on the leaves.
- The disease inhibits the process of photosynthesis due to which growth of the plants is badly affected and ultimately the yield is reduced.
Control
- Use resistant varieties
- Sow the seeds after treatment with fungicides e.g Toprin-M @ 2gm/kg of seed
3. Downy Mildew of Sorghum
Symptoms
- Affected seedlings have pale yellow narrow leaves.
- Leaves are shredded off.
- The plants remain stunted and sterile.
- No ear formation, if ears are produced those are of small size.
Control
- Crop rotation
- Use of resistant varieties
- Destruction of plant disease debris.
i. Rust of Sorghum
Symptoms
- Bright purplish, red spot appear on the surface of the leaf especially on the underside of leaf.
- Small brown or reddish uredo-postules appear on the leaves.
- These uredia are elongated & parallel to veins.
Control
- 4-5 application of navam and zinc sulphate starting from the stage of infestation.
- Some antibiotics are also suitable but not practicable to cover large areas.
ii. Grain Smut of Sorgham
Symptoms
- Ovaries are attacked.
- Ovaries in an infected ear are formed into smut sorus.
- Generally the ovaries are replaced by dirty grey sac of smut sorii.
Control
- Seed should be treated with fungicide before sowing.
- Organic mercuric compounds are suitable.
- Sulpher dusting is also effective.