Studies on the seasonal incidence and management of citrus psylla (Diaphorina citriKuwayama) in sweet orange

Abstract

Field experiment was conducted during 2013 to study the seasonal incidence and efficacy of various insecticides and bio-rationals against citrus psylla in sweet orange. The results revealed that the peak nymphal population of citrus psylla was observed in the month of February-March and August-September and it was low in May-June and December. The reduction in the pest coincided with reduction in new flushes during April to June months and decreased with low temperature in November and December months and increased in temperature from May to June month. Among the different insecticides evaluated against citrus psylla, the treatment with abamectin 1.9 EC @ 0.4 ml/l (0.0007%) was found most effective in recording the least nymphal population of citrus psylla at 3rd, 7th and 14th days after sprays over rest of the treatments. The next best treatment was imidacloprid 17.8 SL @ 0.25 ml/l (0.004%). Dimethoate (0.06%) recorded 18.18, 13.94 and 9.35 population of citrus psylla nymphs at 3rd, 7th and 14th days after sprays whereas bio-rationals i.e. V.lecanii and B.bassiana recorded 33.97, 22.13 ,17.97 and 39.00,33.18,28.32 respectively at 3rd, 7th and 14th days after sprays.