Screening of rice accessions and newer molecules against lepidopterous pests in Manipur, India

Abstract

Trials conducted to assess the resistant reaction of some rice accessions and evaluation of newer molecules against the incidence of two key lepidopterous pests viz., Scirpophaga incertulas Walker and Cnaphalocrocis medinalis Guenee revealed that among the screened varieties, WR-15-6-1, WR-1-9-1-1, CAU-R2, Lamyanbaphou, RC-MANI-PHOU-11, Matamphou, KD-6-18-7-1 and RCMANIPHOU-6-RC-5 reacted moderately susceptible at vegetative stage and among these eight, four varieties viz., WR-1-9-1-1, CAU-R2, RC-MANI-PHOU-11 and Matamphou showed resistant reaction at heading stage against S. incertulas and six accessions viz., WR-1-9-1-1, CAU-R3, KD-5-3-14, RCMANI-PHOU-11, CAU-R4 and KD-6-18-7-1 were categorized as moderately susceptible to C. medinalis. The test on efficacy of newer molecule showed that treatment with Fipronil 5 SC @ 100 ml a.i. ha1 was found to be most effective in reducing Deadheart (DH) and White Ear Head (WEH) with minimum incidence of 3.85 per cent and 1.87% WEH respectively. Whereas the pooled mean data of two spray indicated that Imidacloprid 17.8 SL @ 250 ml a.i. ha1 showed minimum leaf damage of 4.16 % which was at par with Flubendiamide 39.35 SC @ 50 g a.i. ha-1 (4.63% LD), Fipronil 5 SC @ 100 ml a.i. ha-1.