INTEGRATED MANAGEMENT APPROACH FOR CONTROL OF THE PEST COMPLEX OF OLITORIUS JUTE, CORCHORUS OLITORIUS L.

摘要

Field trials were conducted with six treatments against the pest complex of olitorius jute var. JRO-524 during 2004 and 2005 at Bidhan Chandra Krishi Viswavidyalaya, West Bengal, India. The results revealed that incidence of Anomis sabulifera Guen., Spilarctia obliqua Wlk., Myllocerus discolor Bohemus, Apion corchori Marshall and Polyphagotarsonemus latus Banks were found causing a minimum of 6.10, 4.68, 12.38, 5.09, and 10.47 percent plant infestation, respectively. These were the results from the 2004 crop season in the IPM module M-3 designed against insect, mite and nematode pests as compared to the other treatments. Similar results were obtained in 2005 with a relatively low plant infestation of 7.66, 28.60, 11.90 and 11.21 caused by A. sabulifera, M. discolor, A. corchori and P. latus, respectively, in module M-3 as compared to the other treatments. The maximum reduction (69.39 to 82.46%) of root-knot nematode (Meloidogyne incognita Chitwood) population along with low gall index (1.33 to 1.67) at harvest was observed in module (M-3) in 2004-05. The yellow mite population was observed to be a minimum of 14.33 and 19.33 per leaf in 2004 and 2005, respectively in M-3. The maximum average fiber yield of 30.32 q/ha and the benefit-cost ratio of 7.34 were also recorded in M-3. Based on the benefit-cost ratio, the performance of the treatments was in the decreasing order of M-3 > M-2 > M-4 > M-5 > M-1 > M-6. Considering performance for managing insect, mites and root-knot nematodes, M-3 was the most effective and economical management strategy against the pest complex of olitorius jute. Four spider species viz. Neoscona mukerji Tikader, Neoscona sp., Araneus sp. and Xysticus sp. were recorded for the first time in the jute ecosystem of West Bengal. The pest population in the jute ecosystem could be suppressed naturally to a great extent, because thirteen insects and ten spider predators were encountered in the experimental field during the crop season. Furthermore, a larval parasitoid (Apanteles obliquae) was found acting on the larvae of bihar hairy caterpillars.