The Tamil Nadu Agricultural University has advised farmers to monitor the crop regularly following the detection of various pests and bug attacks on rice, cotton, sugarcane, black gram, papaya and tapioca which is expected in this season.
According to a release from the university, information regarding the incidence of pest attacks and steps needed to control them were based on the findings of the Department of Agricultural Entomology and Department of Plant Pathology of the university.
The incidence of stemborer and leaf folder in rice fields were noticed in Salem, Villlupuram, Tirunelveli, Dharmapuri, Tiruchi and Thiruvarur. Farmers are advised to set up light traps to help control the movement of adult moths. For increased damage, spraying of Neem Seed Kernel Extract (NSKE) 5 per cent, Profenophos 50EC 400 ml an acre or Chlorpyriphos 20EC 500 ml an acre are suggested. In case of false smut found due to unusual rains, farmers were advised to spray Propiconazole at one gram a litre of water.
Aphids, jassids, bollworm and cotton mealy bug caused damages to cotton fields in Theni, Dindigul, Dharmapuri, Tirunelveli and Virudhunagar. Aphids and other sucking pests could be monitored by sticky tapes at 5 an acre. NSKE 5 percent, Imidacloprid 40 ml an acre or Dimethoate 200 ml an acre could be used too. Regarding bollworm damage and cotton mealy bug, Quinalphos or chlorpyriphos 2 ml a litre of water is expected to address the problem.
For sugarcane, farmers were advised to release 6 releases of Trichogramma egg parasitoid to avoid shoot borer and internode borer damage at the rate of 1 ml an acre per release starting from the 45th day Dharmapuri, Villupuram, Thiruvarur, Salem and Thanjavur
Yellow mosaic virus, prevalent in black gram in Virudhunagar and Thanjavaur, and in cucurbits in Coimbatore, could be monitored using yellow sticky tapes. If movements of vector whitefly were noticed, dimethoate and methyl demeton sprays could be made use of at the rate of 2 ml a litre of water.
The attacks of papaya mealy bug were found to be more in tapioca than papaya in Udumalpet, Karur, Erode, Ramanathapuram and Madurai. Introduction of the parasitoid, Acerophagus Papayae had brought down the bug rate to a negligible level in papaya gardens in Tamil Nadu.
The university is into a mass production of this parasitoid in all colleges, Research Stations and Krishi Vigyan Kendras (KVKs). This could be obtained free of cost by the farmers.
Farmers are also asked to avoid use of insecticides to conserve natural enemies.
For details, contact the Department of Agricultural Entomology on 0422-6611214 or Department of Plant Pathology on 0422-6611226.