Analisis mekanisme resistensi terhadap Fipronil pada wereng batang padi cokelat (Nilaparvata lugens)

BUDIYANTY, Novi, Prof.Dr.Ir. Y. Andi Trisyono, M.Sc

2006 | Tesis | S2 Ilmu Hama Tumbuhan

Penelitian ini bertujuan untuk mengetahui mekanisme resistensi dan tingkat resistensi wereng batang padi cokelat, Nilaparvata lugens, terhadap fipronil. Seleksi di Laboratorium dilakukan selama tiga generasi secara terus menerus (F54 – F56) pada populasi resisten. Uji hayati dilakukan dengan menggunakan metode celup daun terhadap nimfa instar tiga. Nilai LC50 populasi N. lugens yang sudah terseleksi adalah 239,07 ppm, dengan tingkat resistensi sebesar 47,8 kali bila dibandingkan dengan populasi peka. Penambahan DEF (s,s,s-tributyl phosphorotrithioate), PBO (Piperonyl butoxide), DEM (Diethyl maleate) yang merupakan sinergis dengan fipronil, 100 ppm untuk tiap sinergis menunjukkan efeek yang sinergis. Nilai sinergis rasio DEF, PBO dan DEM adalah 7,9; 9,5 and 23, secara berturut-turut. Penambahan DEM pada populasi resisten efektif dalam menurunkan nilai LC50 fipronil menjadi 10,38 ppm, hal ini mengindikasikan glutathione S-transferase merupakan enzim utama yang berperan dalam mekanisme resistensi terhadap fipronil. Esterase, MFO (mixed function oxidase) dan glutathione S-trasnferase terdeteksi pada profil protein baik pada populasi peka maupun resisten. Pita protein yang memiliki berat molekul 25 KDa diduga sebagai glutathione S-transferase, pada populasi resisten intensitasnya lebih tinggi dibandingkan pada populasi peka. Aktifitas enzim esterase non spesifik pada populasi resisten dan populasi peka sama.

This research was aimed to determine the resistance level of brown planthopper, Nilaparvata lugens, to fipronil and the mechanisms of resistance. Laboratory selections were carried out for three continuous generations (F54 – F56) on resistance population. All bioassays were done using leaf dip method, against third instars. The LC50 value of selected N. lugens was 239.07 ppm. showing the resistance level of 47.8 times than the susceptible population. The addition of DEF (s,s,stributyl phosphorotrithioate), PBO (Piperonyl butoxide), DEM (Diethyl maleate) as synergist with fipronil, using 100 ppm each synergist, showed effect of synergism on resistance population. The value of synergism ratio were 7.9; 9.5 and 23 for DEF, PBO and DEM respectively. The addition of DEM on resistance population was effectively reduced the value of LC50 (10.38 ppm), it indicate that glutathione Stransferase as a major mechanism toward fipronil. Esterase, MFO (mixed function oxidase) and glutathione S-transferase were present on the protein profile not only on the resistance population but also on the susceptible population. The band with molecular weight 25 KDa suspected to be glutathione S-transferase on the resistance population had a higher intensity than that on the susceptible population. The activity of esterase non specific on the resistance and susceptible population was simila r.

Kata Kunci : Wereng Batang Padi Cokelat,Fipronil, Resistance mechanism, Fipronil, Nilaparvata lugens, Synergism