Determination of the Efficacy of Bitter Leaves (Vernonia Amygdalina) Biochar as Bio-Pesticide Against Sitophilus Zeamais

Post-harvest storage of grains with chemical pesticides, which are harmful to human health, prompted this experiment. The study, carried out at the Laboratory and Farm of the Department of Agricultural Technology, Federal Polytechnic, Ile-Oluji, Nigeria, used natural means of storing the grains. Biochar from Bitter Leaves (Vernonia amygdalina) was applied to stored maize infested with Sitophilus zeamais to investigate its effect on the susceptibility index, mortality rate, and germination percentage of the maize. The experiment used a Completely Randomized Design with four Bitter Leaves Biochar (BLB) treatments as 0g, 5g, 10g, and 15g repeated thrice for each of the treatments. Each of the results showed that the control treatment recorded the highest Susceptibility Index (57%), while the lowest value (13%) was recorded at 15 g BLB. In contrast, the control treatment recorded the lowest mortality (12%) and germination percentage (40%). Mortality increased progressively with increasing BLB rate, from 45%, 63%, and 73% at 5, 10, and 15 g BLB, respectively. Similarly, germination percentage increased from 40% in the control to 65%, 73%, and 86% at 5, 10, and 15 g BLB, respectively. The findings show that increasing BLB application rates enhanced the mortality of Sitophilus zeamais while improving the germination percentage of stored maize. Bitter Leaf Biochar therefore shows considerable potential as a botanical biopesticide for the management of Sitophilus zeamais in stored maize.

Bitter leaf Biochar; Sitophilus zeamais; Susceptibility Index; Mortality; Germination Percentage

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