Onion diseases and control measures

Major Onion Diseases are:-


Onion Diseases

 1.  Basal Rot: Fusarium oxysporum f.sp. cepae  

onion basal rot

 2.  Downy mildew: Peronospora destructor  onion downy mildew
 3.  Leaf Blight (Blast): Botrytis spp.  Leaf blight of cotton
 4.  Pythium root rot: Pythium aphanidermatumP. debaryanum and P. ultimum  Onion Root rot
 5.  Smut: Urocystis cepulae  Onion smut
 6.  White Rot: Sclerotium cepivorum  onion white rot
 7.  Purple blotch: Alternaria porri  onion purple blotch


Basic precautions in pesticides usage

A. Purchase

1. Purchase only just required quantity e.g. 100, 250, 500, 1000 g/ml for a single application in specified area.

2. Do not purchase leaking containers, loose, unsealed or torn bags.

3. Do not purchase pesticides without proper/approved labels.

4. While purchasing insist for invoice/bill/cash memo


B. Storage

1. Avoid storage of pesticides in house premises.

2. Keep only in original container with intact seal.

3. Do not transfer pesticides to other containers.

4. Never keep them together with food or feed/fodder.

5. Keep away from the reach of children and livestock.

6. Do not expose to sunlight or rain water.

7. Do not store weedicides along with other pesticides.


C. Handling

1. Never carry/ transport pesticides along with food materials.

2. Avoid carrying bulk pesticides (dust/granules) on head shoulders or on the back.


D. Precautions for preparing spray solution

1. Use clean water.

2. Always protect your nose, eyes, mouth, ears and hands.

3. Use hand gloves, face mask and cover your head with a cap.

4. Use polythene bags as hand gloves, handkerchiefs or piece of clean cloth as a mask and a cap or towel to cover the head (Do not use polythene bag contaminated with pesticides).

5. Read the label on the container before preparing spray solution.

6. Read the label on the container before preparing spray solution.

7. Prepare the spray solution as per requirement

8. Do not mix granules with water

9. Concentrated pesticides must not fall on hands etc. while opening sealed container. Do not smell pesticides.

10. Avoid spilling of pesticides while filling the sprayer tank.

11. Do not eat, drink, smoke or chew while preparing solution

12. The operator should protect his bare feet and hands with polythene bags


E. Equipment

1. Select right kind of equipment.

2. Do not use leaky and defective equipment

3. Select right kind of nozzles

4. Don’t blow/clean clogged nozzle with the mouth. Use old tooth brush tied with the sprayer and clean with water.

5. Do not use the same sprayer for weedicide and insecticide.


F. Precautions for applying pesticides

1. Apply only at recommended dose and dilution 89

2. Do not apply on the hot sunny day or strong windy condition 3. Do not apply just before the rains and after the rains. 4. Do not apply against the

3. Do not apply just before the rains and after the rains.

4. Do not apply against the wind direction

5. Emulsifiable concentrate formulations should not be used for spraying with battery operated ULV sprayer

6. Wash the sprayer and buckets etc. with soap water after spraying

7. Containers buckets etc. used for mixing pesticides should not be used for domestic purpose

8. Avoid entry of animals and workers in the field immediately after spraying

9. Avoid tank mixing of different pesticides


G. Disposal

1. Left over spray solution should not be drained in ponds or water lines etc. throw it in barren isolated area if possible

2. The used/empty containers should be crushed with a stone/stick and buried deep into soil away from water source.

3. Never reuse empty pesticides container for any other purpose.




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