Evaluation of an integrated management package to reduced preharvest seed infection by Aspergillus flavus in groundnut

Two treatments, an integrated aflatoxin management package (IAMP) and normal farmers' practice were compared in Alfisol fields at ICRISAT, Patancheru, Andhra Pradesh, India during kharif 2001. The IAMP consisted of summer ploughing of the field, seed treatment with carbendazim (Bavistin 50 WP) at 4 g/kg seed, furrow application of Trichoderma harzianum at 50 g culture mixed in 50 kg FYM before sowing (to make a final population of 1 × 106 CFU/g soil), spray of Nimbucidin (250 ml in 50 litres water) and a second spray of carbendazim (50 g) plus Dithane M-45 [mancozeb] (250 g) in 50 litres of water, if required, harvesting at 75% maturity, drying by inverted windrows for 3 days, and removal of damaged and diseased pods. The farmers' practice was summer ploughing, harvesting at full maturity, drying by leaving them in the field and removal of damaged pods. No chemical treatments were involved. For both treatments A. flavus strain Af 11-4 inoculum was applied at 50% flowering stage. Soil was sampled prior to sowing, before inoculum application and at harvest. Colonization of seeds by A. flavus was determined and aflatoxin contamination estimated by ELISA. Soil sample analysis showed unremitting growth of A. flavus in soils where farmers' practice was followed. Seed infection studies revealed predominance of A. flavus infection in plots under farmers' practice (10%) compared with that under IAMP (2%). No aflatoxin contamination was recorded in seed samples from plots subjected to either practice