Efficacy of phosphine and neem oil as fumigant against pulse beetle Gandhi B. Kiran*, Srivastava Chitra Division of Entomology, ICAR-Indian Agricultural Research Institute, New Delhi, 110012 *Division of Crop Protection, ICAR-Indian Institute of Pulses Research, Kanpur, 208024, Email: bkg0530@gmail.com (corresponding author) Online published on 24 October, 2019. Abstract A laboratory experiment was carried out to understand the toxicity of phosphine and neem oil on adults of pulse beetles Callosobruchus maculatus and C. analis. Phosphine gas at 0.0125 mg/L dosage was relatively more toxic to C. maculatus (80% mortality) than C. analis (56.67%). Among neem oil and solvents combinations, neem oil in ethanol at 135 mg a.i/L dosage, resulted in 83.33% and 73.33% mortality in C. maculatus and C. analis, respectively. Probit analysis revealed neem oil in ethanol (151.24 a.i mg/l) and water (85.04 mg a.i/l) had low LC50 values with C. maculatus, while C. analis was observed with high LC50 (176.59 mg a.i/l and 102 mg a.i/l) with neem oil in ethanol and water, respectively. Thus an organic fumigant neem oil at high dosage led to more or equal adult pulse beetle mortality compared to inorganic phosphine at low dosage. Top Keywords Callosobruchus maculatus, C. analis, adults, fumigant, LC50, phosphine, neem oil, ethanol, water, bioassay. Top |