Toxicity Bacillus thuringiensis-based Bio Insecticide Enriched with Golden Snail Meat Flour Against Worker and Soldier Castes of Coptotermes Curvignathus (Isoptera: Termitidae)

Dept. of Plant Protection, Faculty of Agriculture, Universitas Sriwijaya, Indonesia

Abstract

Subterrane an termites Coptotermes curvignathus are important pests in plantation crops, especially rubber and oil palm. Biological control using entomo pathogenic bacteria Bacillus thuringiensis is safe and eco-friendly. The aim of study was to investigate production of B. thuringiensis propagated in media of coconut water and rice washed water enriched with golden snail meat flour as well as its toxicity to soldier caste and worker termites. The study was carried out at Biological Control Laboratory, Department of Plant Protection Faculty of Agriculture, Sriwijaya University, from May to August 2018. The research was arranged with a Completely Randomized Design (CRD) with addition of golden snail meat flour treatment i.e. 2, 5, 8, 11, 14 g respectively and without any meat flour addition in media Nutrient Broth as a control. The highest spore density obtained will be used for bioassays toward worker caste, soldier caste and a mixture of them. The results showed highest spore density was obtained at meat flour addition of 14 g i.e. 5.58 × 10⁷ spores/ml. In toxicity test, it was found that mortality of soldier caste was higher in the treatment without being mixed with worker caste. Many soldiers have large heads with highly modified powerful jaws so enlarged they can not feed themselves. Instead, like juveniles, they are fed by workers.