Evaluation of variable doses of tachnid fly, <i>Sturmiopsis inferens</i> for the management of <i>Sesamia inferens</i> under field conditions in rice and wheat

Abstract

Evaluation of variable doses of tachnid fly, Sturmiopsis inferens for the management of pink stem borer, Sesamia inferens under field conditions in basmati rice (var. Pusa Basmati 1121) and wheat (var. HD 2967) was carried out at a farmer’s field in Ludhiana. Two intervals, i.e. one at 10 days and the other at 15 days were followed for releasing different doses (75, 100, 125 and 150 gravid females/ha) of S. inferens during August-October in rice and November-December in wheat. In case of Basmati rice, the minimum incidence of Sesamia inferens was recorded in treatment where a higher dose of 150 gravid females per ha was released (1.05 % DH at 75 DAT, 1.09 % WE), which was significantly at par with the dose of 125 gravid females per ha. The untreated control plot observed the highest incidence of Sesamia inferens (1.81% DH, 2.11% WE). The observations on grain yield revealed that higher doses of 125 and 150 per ha were significantly superior (37.90-38.41 q/ha) while doses of 100 and 75 per ha were at par with each other (36.35 and 36.91 q/ha, respectively) and minimum grain yield was recorded in untreated plots (34.73 q/ha). In the case of wheat, the minimum incidence was recorded in a treatment where a higher dose of 150 gravid females per ha was released (1.49% DH at 45 DAS, 1.28% WE), which was significantly at par with the dose of 125 gravid females per ha (1.66 % DH at 45 DAS, 1.50% WE). The untreated control plot observed the highest incidence (2.48 % DH at 45 DAS, 2.65% WE). The higher doses of 125 and 150 per ha were significantly superior in terms of grain yield (46.68-47.17 q/ha), while doses of 100 and 75 per ha gave a yield of 45.41 and 44.13 q/ha, respectively.