Uji patogenisitas isolat bacillus thuringiensis berliner dari wilayah endemik DBD di Kalimantan Selatan terhadap larva nyamuk Aedes aegypti Linn

MUHAMAT, Prof. Dr. Jesmandt Situmorang, M.Sc

2009 | Tesis | S2 Biologi

Penelitian ini bertujuan untuk memperoleh isolat B. thuringiensis yang patogenik terhadap larva Ae. aegypti dari berbagai wilayah endemik DBD Provinsi Kalimantan Selatan. Penelitian ini dilakukan mulai bulan Februari 2007 sampai September 2008. Isolasi B. thuringiensis dilakukan menurut metode Ohba and Aizawa (1986). Isolat yang diperoleh diuji patogenisitasnya terhadap larva nyamuk instar 3 dengan waktu perlakuan 24 jam dan 48 jam. Nilai LC50 dan LC90 ditentukan dengan menggunakan analisis probit. Dari sampel tanah sebanyak 361 sampel diperoleh 81 isolat B. thuringiensis. Untuk isolat yang diuji terdapat tiga isolat yang mempunyai mortalitas terhadap larva Ae. aegypti lebih dari 50%, yaitu isolat MA17, C13, dan MA25-1. Nilai LC50 24 jam isolat MA 17, C13, dan MA25-1 secara berturut-turut adalah 2,63x109, 2,88 x 109, dan 1,29x1010 spora/ml. Nilai LC50 48 jam adalah 3,55x108, 1x109, dan 2,88x109 spora/ml. Nilai LC90 24 jam adalah 2,04x1010, 2,34x1010, dan 8,51x1010 spora/ml. Nilai LC90 48 jam adalah 8,27x109, 6,25x109, dan 2,88x1010spora/ml. Berdasarkan pengamatan terhadap bagian abdomen larva Ae. aegypti yang mati, ketiga isolat menyebabkan kerusakan pada bagian usus tengah.

The aim of this study is to obtain pathogenic B. thuringiensis against Ae. aegypti in endemic Dengue Fever (DF) area at South Kalimantan Province. It was conducted from Februari 2007 to September 2008. Isolation method was conducted in accordance with Ohba and Aizawa (1986). The isolates pathogenicity were tested againt Ae. aegypti third instar for 24 hours and 48 hours. The LC50 and LC90 values were determinated using probit analysis. Eighty one isolates of B thuringensis were isolated from 361 soil and water samples. There were three isolates of B. thuringiensis that were able to cause mortality higher than 50% on Ae. aegypti larvae, namely MA17, C13, and MA25-1. The LC50 values 24 hours of MA 17, C13, and MA25-1 were 2,63x109, 2,88x109, and 1,29x1010 spora/ml respectively. The LC50 values 48 hours were 3,55x108, 1x109, and 2,88x109 spore/ml respectively. LC90 values 24 hours were 2,04x1010, 2,34x1010, and 8,51x1010 spore/ml respectively. The LC90 values 48 hours were 8,27x109, 6,25x109, and 2,88x1010spore/ml respectively. Observation on the abdomen of death larvae Ae. aegypti revealed that there were damaged on the mid gut as the result of infection.

Kata Kunci : Bacillus thuringiensis,Aedes aegypti,Pategenik,Endemik DBD,Provinsi Kalimantan Selatan,B. thuringiensis,Ae. aegypti,pathogenicity,DF endemic,South Kalimantan Province