Influence of dibbling time and weather factors on seasonal dynamics of thrips (Thrips tabaci Lindeman) on garlic in Maharashtra

Abstract

A study was conducted for three successive seasons (2014-17) to evaluate the effect of dibbling time on population dynamics of onion thrips (Thrips tabaci) on garlic dibbled on ten different dates starting from 1st September to 15th January at fortnight interval. The significant difference was observed in thrips population load among the dibbling dates. The garlic dibbled on early-December had maximum thrips load (41.8 thrips/plant) followed by both early and late-November sown crop (40 thrips/plant). The least mean of thrips population recorded with early-September planted garlic. Irrespective of sowing dates, highest thrips population peaks were recorded during 1st to 6th Standard Meteorological Week (SMW) of January and February. The maximum average of 59 thrips/plant were registered during early February (5th SMW). The dry spell coupled with optimum temperature (Tmax= 29 to 33°C and Tmin= 9 to 14 °C) favoured thrips population build-up. The correlation analysis between thrips incidence and weather parameters showed significant negative correlation between thrips population and temperature as well as with precipitation.

Keywords

• Thrips incidence
• climatic variability
• sown date
• garlic,
• pest management