Population dynamics and forewarning models for prediction of population of groundnut Thrips under different sowing window and groundnut varieties

Abstract

The correlation was carried out between weather parameter and population of tobacco thrips on different groundnut varieties at different sowing windows and forewarning models for prediction of population of thrips, during kharif season, 2017 and 2018. The experiment was laid out in split plot design with three replications. The treatment comprised of four varieties viz., V1: JL-501, V2: RHRG-6083 (Phule Unnati), V3: TAG-24 and V4: JL-776 (Phule Bharati) as main plot and four sowing windows viz., S1: 25rd MW (18th to 24th June), S2: 26th MW (25th June to 01st July), S­3: 27th MW (2nd to 8th July) and S4: 28th MW (09th to 15th July) as sub plot treatments. The correlation of weather parameters with incidence of thrips, showed that the population of thrips was found to have significant and positive correlation with minimum temperature, afternoon relative humidity, wind speed and bright sunshine hours whereas maximum temperature, morning relative humidity, and rainfall showed negative correlation with seasonal incidence of thrips. Sowing of groundnut during 26th MW (S2) and 27th (S3) recorded lower incidence of thrips, whereas, crop sown during 28thMW (S4) recorded with maximum incidence. Among the groundnut varieties, higher incidence was recorded with TAG-24 and minimum was recorded on JL-776 followed by RHRG-6083. Prediction of thrips populations in different sowing window based on regression equations (R2) 52 to 88 per cent validation based on different weather parameters for variety JL-501, (R2) 58 to 86 per cent validation based on different weather parameter for variety RHRG-6083, (R2) 48 to 85 per cent validation based on different weather parameter for variety TAG-24, (R2) 73 to 83 per cent validation based on different weather parameter for variety JL-776 for the prediction of thrips population.