I see lots of small brown insects sitting low on the stems near the water, and round patches of my dhan are drying up and turning brown like burnt.
3 जवाब
The round drying patches that look burnt, called hopper burn, along with small brown insects clustered at the base near the water line point strongly to brown plant hopper. Part the plants and tap the base over your palm or the water surface to see if the hoppers fall, and show a photo to your KVK or agri officer to confirm it is BPH and not white backed plant hopper, as the management is similar but worth knowing. The most important step is to drain the field for a few days to break the humid base conditions the hopper loves, widen alleys for air movement, and avoid extra nitrogen which makes the attack worse. Avoid broad spectrum sprays that kill the natural enemies like spiders and mirid bugs, since that often triggers a worse resurgence. If a spray is truly needed, target the base of the plant and use recommended actives such as pymetrozine or dinotefuran, but follow the label dose, pre-harvest interval and local KVK recommendation and rotate modes of action. Move fast on the patches because hopper burn spreads outward quickly.
Draining the water for four days made a big difference for me. The hoppers reduced and the spreading patches stopped getting bigger.
I learned the hard way that spraying a strong general pesticide brought the BPH back worse two weeks later. Now I direct the nozzle low at the stem base only.