Efektivitas jamur Entomopatogen Beauveria bassiana untuk pengendalian hama walang sangit

BUDIYONO, Suharto, Dr.Ir. Y. Andi Trisyono, M.Sc

2005 | Tesis | S2 Agronomi

Penelitian ini bertujuan untuk mengetahui efektivitas jamur entomopatogen Beauveria bassiana terhadap walang sangit (Leptocorisa oratorius F.). Isolat yang digunakan berasal dari walang sangit yang terinfeksi B. bassiana, lalu diperbanyak dalam media beras. Walang sangit dikumpulkan dari lapangan dan dikembangbiakan di rumah kaca. Uji hayati (bioassay) dilaksanakan dengan menyemprotkan B. bassiana (3,2 ml/rumpun) konsentrasi 3,2 x 10² sampai 3,2 x 10¹² konidia/ml pada tanaman padi yang telah dilepas walang sangit di kurungan kasa. Nilai LC₅₀ B. bassiana terhadap walang sangit dewasa adalah 3,8 x 10⁸ konidia/ml dengan masa pemaparan selama satu minggu. Stadium walang sangit mempunyai tingkat kepekaan yang berbeda terhadap B. bassiana. Untuk mencapai mortalitas ≥ 60% pada instar 1, 3 dan dewasa berturut-turut dibutuhkan 3,8 x 10⁸; 3,8 x 10⁹; dan 3,8 x 10¹⁰ konidia/ml. Walang sangit yang telah disemprot dengan B. bassiana dan mampu hidup mengalami penghambatan pertumbuhan dan mengakibatkan kerusakan bulir yang rendah dibandingkan kontrol. Walang sangit dewasa hasil dari nimfa yang telah disemprot dengan B. bassiana menghasilkan telur yang lebih sedikit dibandingkan dengan kontrol dan persentase telur yang menetas juga lebih rendah.

The objective of this research was to determine the effectiveness of the entomopathogenic fungi Beauveria bassiana for controlling the rice bug (Leptocorisa oratorius F.). An isolate was obtained from the infected rice bugs in the Regency of Bantul and the starters of rice bugs were collected from field and reared in the green house. The rice bugs were released into the rice plants in the cages. Bioassays were carried out by spraying the rice plant with the intended concentrations of B. bassiana (3.2 ml/hill). The LC₅₀ value of B. bassiana was 3.8 x 10⁸ conidia/ml for one week exposure. The first instar was found to be more receptible than those of the third instars and adults. To reach ≥ 60% mortality for these stadia, it took the concentration of B. bassiana as much as 3.8 x 10⁸, 3.8 x 10⁹, and 3.8 x 10¹⁰ conidia/ml, respectively. The nymphs survived from applications of B. bassiana grew at a lower rate than the control and caused less damage on the rice seeds. Further more, females produced from the treated nymphs yielded significantly less number of eggs than those of the control females. These eggs hatched a lower rate than those produced by the control females.

Kata Kunci : Hama Walang Sangit,Jamur Entomopatogen Beauveria bassiana, Effectiveness, Beauveria bassiana and rice bug