Effect of Cultivars and Botanicals on the Incidence of Major Insect Pests in Lowland Rice

Abstract

A field experiment was conducted during the wet season of 2011 at the experimental farm of ICAR Complex for North East hill region, Jharnapani, Medziphema, Nagaland using Split Plot Design to study on the effect of cultivars and botanicals on the incidence of major insect pests in lowland rice. A rice variety, Ranjit and two rice cultivars, Miracle rice and Jalukie special were selected and three major pests were taken into account for the study. Peak incidence of rice stem borer and leaf folder in all the three varieties were observed at 105 days after transplanting of the crop. Jalukie special harboured the maximum number of borer population (26.67%) followed by ranjit (26.30%) and miracle rice (23.00%). Leaf folder incidence was maximum in ranjit (29.47%) followed by miracle rice (27.83%) and lowest incidence was in jalukie special (27.33%). The incidence of ear head bug was observed from 60 days after transplanting till harvest. Peak incidence was observed at 120 days after transplanting. Incidence was highest in ranjit (4.43 bugs 5 sweeps-1) followed by Miracle ice (3.57 bugs 5 sweeps-1) and Jalukie special (3.13 bugs 5 sweeps-1). Among the botanical treatments, Litsea citrata seed extract was found to give effective control against the three pests almost at par with Monocrotophos. Crude stem extract of Costus speciosus and seed extract of Chenopodium ambrosioides were also found to be effective in reducing the pests.