Bacillus thuringiensis propagated in bio-urine media as a biological control of termite Coptotermes curvignathus and armyworm Spodoptera litura

Abstract

Biological control using entomopathogenic bacteria Bacillus thuringiensis is in increasing demand because of its specific target toxicity, safe for natural enemies as well as pollinating insects. Propagation media for B. thuringiensis greatly determines the success of spores number produced and toxicity level to insect pests. This study aimed to record the spore density of indigenous isolates of South Sumatera propagated in bio-urine and 5% molasses media and their toxicity level against termites Coptotermes curvignathus and armyworm Spodoptera litura. The research was conducted at Biological Control Laboratory, Plant Protection Study Program, Faculty of Agriculture, UNSRI, from March to June 2019. The study was designed with Factorial Completely Randomized Design, using isolates as many as 3 isolates with 3 media treatments (bio-urine, bio-urine + 5% molasses, and Nutrient Broth) and 5 replications. The bio-assay used worker caste termites and 3rd instar armyworms. The results showed that a mixture of bio-urine and 5% molasses produced higher number of spores compared to bio-urine media only. The use of NB as a control showed higher spore production compared to the 2 other treatments. The mortality rate of Coptotermes termite was higher than the mortality rate of armyworms. Death symptoms of insect pests were indicated by the presence of wet rot and color change (blackish).

Pemanfaatan Limbah Ternak sebagai Media Pembuatan Bioinsektisida Berbahan Aktif Bacillus thuringiensis dalam Mendukung Pengendalian Hama Terpadu

“…Bacillus thuringiensis merupakan salah satu bakteri entomopatogenik yang dapat digunakan untuk pengendalian serangga hama, dengan cara memperbanyaknya pada media yang mengandung unsur karbon dan nitrogen. Berdasarkan pengalaman Pujiastuti et al (2020) B. thuringiensis ini dapat diperbanyak pada limbah cair ternak dan dapat tumbuh dengan baik. Sifat toksik didapatkan karena adanya spora dan kristal protein yang diperoleh saat sporulasi (Bravo et al, 2013).…”

“…Selanjutnya bio-urine tersebut disaring dan dapat digunakan untuk menumbuhkan bakteri B. thungiensis. Selanjutnya ditambahkan sebanyak 1 L seed culture yang disiapkan di laboratorium Fitopatologi PS Proteksi Tanaman Fakultas Pertanian UNSRI (Pujiastuti et al, 2020) dan ditambahkan 100 g gula merah (1% w/v) (Wahyuono, 2015). Fermentasi dilakukan selama satu minggu, selanjutnya siap untuk diaplikasikan sebagai bioinsektisida pada tanaman cabai.…”

Effectivity of Bacillus thuringiensis from Soil in Freshwater Swamps against Epilachna sp. Larvae

“…Soil sample was taken when swamp land was not cultivated by rice. This isolate was bioassayed against Spodoptera litura (Lepidoptera: Noctuidae) (Pujiastuti et al, 2018a), Coptotermes curvignathus (Isoptera: Termitidae) (Pujiastuti et al, 2018b) and other insects (Pujiastuti et al, 2020a).…”