My tomato plants suddenly wilt and die even though the leaves stay green and the soil is moist. Cut stems ooze a milky stream. What is this?
4 जवाब
Sudden wilting of green plants with moist soil, where a cut stem placed in clear water gives a milky ooze, points to bacterial wilt caused by Ralstonia, a soil borne bacterium that is very hard to cure once the field is infested. Management is mainly prevention and cultural. Use resistant or tolerant varieties and grafted seedlings on resistant rootstock where available, which is one of the few reliable tools against this disease. Follow long crop rotation away from tomato, brinjal, chilli and potato, since these all host the bacterium, and avoid planting in fields with a known wilt history. Ensure good drainage as waterlogging spreads it, remove and destroy wilted plants, and avoid moving infested soil and water from sick patches to clean ones. There is no spray that cures it. Raising soil organic matter and bio agents may help, so ask your KVK about resistant varieties, grafting and rotation for your field.
The clear water test confirmed it for me, cut a piece of the wilted stem and hang it in clear water and the milky thread streaming out is the giveaway. Once I knew it was bacterial wilt I stopped wasting money on fungicide sprays that do nothing for it.
Grafted seedlings on a resistant rootstock made my tomato possible again in a wilt sick field. The plants survived where ungrafted ones died in patches. They cost more but in a known wilt field they were worth it. Ask whether grafted plants are available in your area.
Watch that you are not carrying the bacterium on your feet and tools and irrigation water from a sick patch to a clean one. I think I spread it across my field through the flood water. Good drainage and not letting water run from infected spots to healthy ones slowed it.