Leaves turning yellow on Thailand long bean plants

Bean    Thailand

My Thai family are having problems with newly planted long beans. Recently the leaves are turning a mottled yellow and they are thinking of digging them all up and starting again. I was wondering if there could be a soil based problem that we could correct to save them losing their hard work to date.

Any advice on options would be much appreciated.

Posted by: Tony Eastmead (1 point) Tony Eastmead
Posted: March 13, 2020


Dear Tony Eastmead,
Your beans are infected by a virus and the infection seems to be severe. It is better to do a rotation by replacing the beans with another crop.
For next time they are planning to plant bean, they need to use clean certified seeds since many bean viruses are seed transmitted.
Let us know if you have more questions.

Posted by: Rimnoma Serge Ouedraogo (6 points) Rimnoma Serge Ouedraogo
Posted: March 14, 2020

It looks like one of potyviruses infecting legumes. Most of them are insects-transmitted. These viruses severely reduce yield, so it is better to remove infected plants and use insecticides to control virus vectors. Weeds can be a main source of infection, but seeds sometimes too.

Posted by: alex ignatov (33 points) alex ignatov
Posted: March 14, 2020

Typical of dry season, that insects such as aphis will infest on crops and bring along virus intection. Suggest to clear out infected plants and use insecticide (early morning or late pm spraying) to protect the healthy ones. guess by now, your crop must have yeilded and gradually harvested

Posted by: Nantawat Suthiwanich (1 point) Nantawat Suthiwanich
Posted: April 19, 2020

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