Evaluation of Some Essential Oils against Pulse Beetle (Callosobruchus chinensis L.) in Pea Seeds

Abstract

The present investigations on“Evaluation of some essentials oils against pulse beetle (Callosobruchus chinensis L.) in pea seeds” were carried out during 2014-15 in the Department of Seed Science and Technology, College of Horticulture, Dr. Y.S. Parmar University of Horticulture and Forestry, Nauni–solan (H.P). The essentials oils of camphor, wild marigold, cone-bearing sage, eucalypts, lemongrass and sweet flag at 2.5 ml/kg, 1.25 ml/kg, 0.60 ml/kg and 0.30 ml /kg (v/w basis)were evaluated against C. chinensis L. infesting pea seeds. Among the six essentials oils, sweet flag possessed reasonably high and immediate toxicity resulting in 78.33 percent and 96.67 percent (2.5 ml/kg and 1.25 ml/kg doses resulted 100 % mortality) mortality in 1 and 3 days after treatment. After 7 days, cent per cent mortality was observed in seeds coated with sweet flag essential oil followed by eucalypts (85.83%) cone - bearing sage (77.50%), camphor (74.17%), lemongrass (71.66%) and wild marigold (61.67%) in descending order. After 10- days of exposure, eucalypts essential oil also resulted in complete kill even at the lowest dose (0.30ml/kg). On day -15, mortality in control had substantially increased to 67.50 percent. Egg laying was minimum on sweet flag essential oil treated pea seeds (5.25 eggs/5 females) on 7th – day of observations. In untreated pea seeds, increases in egg laying was negligible in 20 – days observations (7th day 94.08- 20th day 101.92). Progeny development from the eggs laid on pea seed treated with sweet flag essentials oil was (1 beetle).