Fungal diseases 1. Black mould 2. Neck rot 3. Blue mould 4. Soot Bacterial diseases 1. Brown rot The inner part of the onion gets rotten and becomes brown. The rot starts from the inner part and spreads to the outer cover. Disease Management: To avoid losses, various measures should be taken right from the onion cultivation till storage. Seed treatment - It is important to do the seed treatment before sowing. Before using seeds, Carbendazim should be used to treat the seeds @1 gm/kg and then seeds should be sowed. Cultivation - Trichoderma 2 kg/acre mixed with FYM should be given to the farm. If 80 kg Urea, 50 kg 18:46, 50 kg Potash and 10 kg Sulphur is given to the onion crop, we can get good quality produce and it helps for having longer shelf life of onion. When transplanting the onion saplings, they should be dipped in 0.2% solution for 10 to 15 minutes and then should be planted. Sprayings - 10 to 15 days before the harvesting of onion, Carbendazim 2 gm + Streptocyclin 0.1 gm/liter of water should be sprayed. Harvesting of onion- When the necks of more than 50% onions droop down, the onions should be harvested along with the leaves. After harvesting, dry them for 2 to 3 days in the farm itself. Pruning of onion - Most pathogens enter from the neck of onion. So pruning should be done at 2 to 3 cms from the neck of the onion. Pruned onions should be dried in the shade for 15 days. Storage- Onion storage (chawl) should be at some height and at a well-ventilated place where water is well drained. Two eave roofed onion storage should be in the east-west direction. Before storing the onion in the storage, the empty place should be sprayed with 0.2% Carbendazim. Onion should be stored up to 3 to 4 feet. Every 1.5 to 2 months, rotten onions should be selected and separated.