Impact of Lantana camara hexane extract on survival, growth and development of Dysdercus koenigii Fabricius (Heteroptera: Pyrrhocoriedae)

Abstract

Present research work investigated the impact of hexane extract of Lantana camara leaves on the survival, survival duration, growth and development of the Dysdercus koenigii. Newly emerged fifth instar nymphs were exposed to nine concentrations viz. 10%, 5%, 2.5%, 1.25% 0.1%, 0.05%, 0.025%, 0.0125% and 0.00625% of the extract by ‘dry film residual method’ for 24h. The results indicated that the survival and the growth of the nymphs decreased with increasing concentrations of the L. camara extract. The nymphs presented developmental malformation including incomplete moulting followed by death of the moulting nymphs, supernumerary nymphal instars, adults with wing deformities, and adults with exuviae attached to the body. The GC–MS analysis of the extract indicated presence of phytoconstituents with insecticidal activities, and intermediates of the juvenile hormone biosynthetic pathway. It was surmised that these intermediates individually or synergistically influence JH biosynthesis. L. camara extract causes mortality, inhibits growth and development and results in developmental anomalies in the D. koenigii thus indicated its potentials in the ‘integrated pest management’.