Bio-efficacy of some novel insecticides against Nilaparvata lugens (Stål) (Hemiptera: Delphacidae) on paddy

Abstract

An experiment was carried out under field condition to studythe bio-efficacy of novel insecticides against, Nilaparvata lugens (Stal) (Hemiptera: Delphacidae) on paddy during Kharif season at the Agricultural Research farm of Institute of Agricultural Sciences, Banaras Hindu University (BHU), Varanasi, India. The average number of insects recorded one day prior to the spray was in a range of 10.33 to 12.00 / 10 hills. The overall mean of average number of insects per 10 hills after first insecticidal spray was shown in increasing order as: acetamiprid 20 SP @40g a.i/ha (6.06) < imidacloprid 17.8 SL @50ml a.i/ha (7.04)< difenthiuron 50 SC@300g a.i/ha (7.14) < fipronil 200 SC @ 50g a.i./ha (7.79) < fipronil 0.6GR @ 50g a.i./ha (8.45) < carbofuron 3 GR @ 750g a.i./ha (8.78) < lambda cyhalothrin 4.9 CS @12.5 a.i./ha (9.11). Similar trend was followed after second insecticidal spray with 3.13, 4.04, 4.80, 5.60, 5.80, 6.46 and 8.70 overall mean of insects per 10 hills, respectively. The fipronil 200SC was observed to be best and the plots treated by this chemical gave a yield of 5.67 kg/ plot, but the yield in kg per plot obtained from lambda cyhalothrin (5.53), acetamiprid (5.43) and imidacloprid (5.30), were statistically on par.