Impact of few chemical weedicides and botanicals on the biocontrol agent, Zygogramma bicolorata (Pallister) of Parthenium hysterophorus (Linnaeus)

Abstract

Studies on the Impact of few chemical weedicides and botanicals on the biocontrol agent, Zygogramma bicolorata (Pallister) of Parthenium hysterophorus (Linnaeus) conducted in the Biocontrol laboratory, Indira Gandhi Krishi Vishwavidyalaya, Raipur (C.G.) during in the year of 2021-22, indicated that, the effects of commonly used weedicides (glyphosate, atrazine, 2, 4-D, and metribuzin) and botanicals (marigold, charota, and bantulsi) on adult beetles of the Z. bicolorata, atrazine at both concentrations (0.7 and 0.14 mg), was most toxic for the all stages. Based on biometric parameters the effect of weedicides and botanicals on F1 progenies, minimum length and width (0.73 mm and 0.32 mm) of egg was recorded in atrazine @ 0.14 mg. Similarly, in bantulsi @ 0.50%, minimum length and width of egg were recorded with an average of 0.81 mm and 0.47 mm. Among the larval stages in case of 1st, 2nd, 3rd and 4th instar larvae minimum length (1.10 mm, 3.04 mm, 3.45 mm and 7.11 mm) and width (0.27 mm, 1.05 mm, 2.07 mm and 2.28 mm) respectively recorded in atrazine @ 0.14 mg and maximum length (1.40 mm, 3.16mm, 4.73 mm and 8.16 mm) and width was recorded in charota @ 0.25% compared to the control. In case of pupa and adults (male and female), similar finding was recorded in atrazine and bantulsi in both concentrations.