Potensi Cendawan Endofit asal Padi dan Rumputrumputan untuk Pengendalian Wereng Cokelat Nilaparvata lugens (Stal) (Hemiptera: Delphacidae).

Abstract

Wereng cokelat adalah hama padi terpenting di Indonesia. Pengendalian wereng cokelat dapat dikembangkan dengan berbagai metode. Cendawan endofit berpotensi sebagai agen biokontrol serangga. Penelitian ini bertujuan mengetahui potensi cendawan endofit dalam mengendalikan wereng cokelat. Cendawan endofit diisolasi dari padi dan rumput-rumputan di sekitar Bogor. Sebanyak 12 isolat hasil isolasi, 7 isolat asal padi dan 5 asal rumput-rumputan. Berdasarkan hasil uji patogenisitas, terdapat 5 isolat adalah nonpatogen. Uji selanjutnya dengan menggunakan 4 isolat cendawan endofit, yaitu Acremonium sp., Nigrospora sp.1, Nigrospora sp.2, Nigrospora sp.3. Penggunaan cendawan Nigrospora sp.4 dari koleksi Klinik Tanaman sebagai kontrol positif. Benih padi direndam ke dalam suspensi konidia cendawan endofit selama dua jam dan diperam selama 24 jam. Bibit padi dipindahkan ke ember setelah tanaman berumur 3 minggu setelah semai. Bibit padi disemprot dengan suspensi cendawan endofit seminggu setelah tanam. Tujuh hari setelah inokulasi cendawan endofit, sebanyak 10 nimfa wereng cokelat instar satu diintroduksi ke tanaman padi dan diamati setiap hari selama 7 hari untuk mencatat kelangsungan hidup nimfa. Dalam percobaan lain, 5 pasang wereng cokelat dewasa diintroduksi ke tanaman padi (28 hari setelah tanam) dan diamati setiap minggunya selama 6 minggu. Semua isolat cendawan endofit yang diuji dalam percobaan ini menyebabkan kematian nimfa dan menurunkan populasi wereng cokelat.

Brown planthopper (BPH) is the most important rice pest in Indonesia. We developed many methods to control this planthopper. Endophytic fungi have the potential as biocontrol agents of insects. This study aims to determine the potential of endophytic fungi in controlling BPH. Endophytic fungi were collected from rice and grasses in Bogor. A total of 12 isolates were isolated, 7 from rice and 5 from grasses. Based on test, 5 isolates were nonpathogenic. We used 4 of these isolates for the experiments, Acremonium sp., Nigrospora sp.1, Nigrospora sp.2, Nigrospora sp.3. We also used Nigrospora sp.4 from Klinik Tanaman collection as positive control. Rice seeds were dipped in endophytic conidia fungal suspension for two hours, and then ripened for 24 hours. Rice seedlings were transferred to the planting baskets 3 weeks after sowing. Rice seedlings were sprayed with endophytic fungal suspension a week after planted. Seven days after inoculation of endophytic fungi, 10 first-stage BPH nymphs were introduced and observed daily for 7 days to record nymphs survival. In the other experiment, 5 pairs of adult were introduced in to the rice plants (28 days after treatment) and observed weekly for six weeks. All of endophytic fungi isolates tested in these experiments caused nymphs death and population suppression of BPH.