Evaluation of Integrated Pest Management Modules for the Management of Leafhopper Empoasca flavescent (Fab.) on Castor Ricinus communis
R. Kirankumar
Department of Entomology, Agricultural Research Station, Gangavathi, India.
K. S. Jagadeesh
Department of Entomology, UAS, GKVK Bangalore, India.
K. C. Narayanswamy
Department of Sericulture, UAS, GKVK Bangalore, India.
. Jaisri
Department of Genetics and Plant Breeding ZARS, GKVK Bangalore, India.
B. Sannappa
Department of Studies Sericulture, University of Mysore, Manasagangotri, Mysore, India.
*Author to whom correspondence should be addressed.
Abstract
Castor is an important oilseed crop. The castor bean contains about 50-55% oil. Among vegetable oils, castor oil is distinguished by its high content (over 85%) of ricinoleic acid. No other vegetable oil contains so high proportion of fatty hydroxyl acids. Castor oil’s unsaturated bond, high molecular weight (298), low melting point (5°C) and very low solidification point (-12°C to -18°C) makes it industrially useful, most of all for the highest and most stable viscosity of any vegetable oil. The castor plant has a substantial taproot with many lateral branches which can reach a great depth enabling them to withstand drought and most harsh weather conditions. Leaves of castor plants are large, glossy and green with pointed lobes and prominent veins; however, the castor leaf for many years has often been attacked by the leafhopper and in most cases leads to the destruction of the plant. The leafhopper causes hopper-burn which renders the attacked leaves dry, uneven, curl downward in the shape of an inverted boat, margins turn brown and eventually death of the plant. Among the eight treatments, the lowest leafhopper/plant recorded by the T4 quinolphos and T6 Neem oil 2% recorded as best treatments over rest of the treatments. Significantly highest grain yield at 3730.00 Kg./ha and 3627.63 Kg./ha recorded by T6 Neem oil 2% and T7 Pongamia oil 2% followed by T5 Mahuva oil recorded yield at 3283.30 Kg./ha However the chemical treatments viz., T3 Profenophos 50 EC at 0.03% and T4 quinolphos 25 EC at 0.05% recorded yield at 2956.66 and 2936.00 Kg./ha both at par with each other. While, untreated control recorded the lowest yield at 2426.03 Kg./ha.
Keywords: Castor (Ricinus communis), hopper-burn, leafhopper (Empoasca flavescens), wax bloom