Vol. 8, Issue 5 (2019)

Author(s):
Rashmi Shrivastava and Jyotsana Mishra

Abstract:
Laboratory experiments were conducted to evaluate the preliminary screening efficiency of methanolic extracts of Euphorbia thymifolia (E. thymifolia) plant materials against larvae of Abelmoschus esculentus and Glycine max pests viz. Earias fabia and Diacrisia oblique. The caterpillars were reared on healthy and clean leaves of both plants by keeping it in glass jars. One thousand insects were released in 1 kg of gram seeds capped with muslin cloth for ventilation. Culture were maintained in laboratory under controlled climatic conditions viz. temperature (28±2ËšC), relative humidity (75±5% RH) and a photoperiod of 12: 12 (L:D) hrs in B.O.D. The crude extracts were tested in ten treatments and each treatment with three replications, along with control (methanol). Mortality of both larvae Earias fabia and Diacrisia obliqua were recorded after 24hr in the presence and absence of plant extracts, separately. Finally, LC₅₀ value was calculated. The mortality of Earias fabia and Diacrisia obliqua varied with varied concentration of plant ex-tract. Methanolic crude extracts of E. Thymifolia was more effective against Diacrisia oblique pests having mortality (93.33%) than Earias fabia mortality (76.67 %) in compilation to standard neem oil (26.67, 16.67 % respectively). In conclusion, this botanical pesticide was effective in the control of Earias fabia and Diacrisia oblique, though they do not match the effectiveness of the synthetic pesticide. This botanical pesticide is affordable to low-income farmers. This natural pesticide has the potential for use in agriculture. In this paper, it has been suggested that botanical insecticides should prove most beneficial for farmers in developing countries and managing populations of Earias fabia and Diacrisia oblique.