At a time when climate change is posing a threat to the farm community in the State, an invasion of rice swarming caterpillar or armyworm on lawns and vegetable crops in Wayanad district has caused concern among farmers, who are readying their field for the first rice crop of the season.
Though the pest attack occurs round the year, an outbreak usually occurs during heavy rainfall after a prolonged drought. As there are chances of a pest attack in the succeeding rain spell, the farmers here should adopt steps to manage the pest at farms and other places, Aparna Radhakrishnan, Assistant Professor, Department of Agriculture Extension, College of Agriculture, at Ambalavayal said.
“It is suspected that a sharp decline in rice cultivating area in the State is the major reason for pest infection on alternate host plants such as lawn grass and vegetable crops,” Dr. Aparna said.
“A fully grown larvae has smooth striped pale coloured body and feeds during night and hides during day. It causes damage to the crop. The plant develops leaf holes and will wither away. Chances of revival are low,” Sanju Balan, Assistant Professor, Plant Protection, said.
The detection and management of the pest is important in the initial stage. Neem-based pesticides and biocontrol agent such as Bacillus thuringiensis could be recommended in initial stages of infestation, S. Simi, Assistant Professor, Horticulture, said. “If the infestation is severe, pesticides such as chlorantraniliprole, 3ml/10 litre water, could be sprayed,” Dr. Simi said.
Close to 1.25 lakh hectares of kharif paddy in 13 districts of western Odisha was destroyed in a pest outbreak, recording about 80-90% damage, in 2009, she added.
According to the data available with the Agriculture Department, rice cultivation is spread over 13,337 hectares in Wayanad district.