Incidence of insect and mite pests in French bean in Assam, India

摘要

The present investigation was carried out in the Integrated Crop Research (ICR) farm, Assam Agricultural University (AA U), Jorhat as well as in the Acarology laboratory, Department of Entomology, AA U, Jorhat during 2013-14 and 2014-15 to record pestcomplex on French bean and their incidence. Eight insect pests viz., cutworm, Agrotis ipsilon; aphid, Aphis craccivora; thrips, Scirtothrips dorsalis; pod borer, Helicoverpa armigera; whitefly Bemisia tabaci; leaf beetle, Monolepta signata; leaf miner,Liriomyza sativae; red ant, Dorylus orientalis and two spotted spider mite, Tetranychus urticae were recorded. The incidence of aphid and cut worm was found to be maximum during the 51s' Standard meteorological week (SMW) with 1.33 numbers per twig per plant and 1.0 number per plant, respectively. Highest populations of the mite and thrips were recorded during 5 2"d SMW i.e. 1.23 and 0.97 number per leaf, respectively. The incidence ofpod borer and whitefly was found to be maximum during the 51s' SMW with 1.12 per plant and 52nd SMW with 1.23 numbers per leaf, respectively. The incidence of leaf beetle, leaf miner and red ant was found to be minor.