Sta tus Resistensi Lima Strain Plutella xylostella L. terhadap Formulasi Fipronil, Deltametrin, Profenofos, Abamektin, dan Bacillus thuringiensis - Moekasan, Tony Koestony; Sastrosiswojo, Soedarwo -; Rukmana, T. -; Sutanto, H. -; Purnamasri, I. S.; Kurnia, A. - (Jurnal Hortikultura, 2004)
Toksisitas formulasi insektisidafipronil, deltametrin, profenofos, abamektin, Ba cil lus thuringiensis subsp./var.kurstaki strain EG 7841 (crymax WDG) dan B. thuringiensis subsp./var. kurstaki strain HD-7 (dipel WP) diuji dilaboratorium terhadap lima strain lapangan larva Plutella xylostella (L.) yang berasal dari pusat pertanaman kubis diLembang, Pangalengan, Kejajar/Dieng, Batu, dan Berastagi mulai bulan Sep tem ber 2000 sampai dengan Februari2001. Pengujian menggunakan metode pencelupan potongan daun kubis ke dalam tiap larutan insektisida ujikemudian larva P. xylostella instar 2 dan atau 3 diletakkan pada potongan daun kubis tersebut. Penghitungan nilaiLC50 tiap jenis insektisida yang diuji dilakukan menggunakan pro gram komputer analisis probit. Hasil penelitianmenunjukkan, terdapat perbedaan kerentanan P. xylostella, tergantung pada asal (strain) P. xylostella. Berdasarkannilai LC50 insektisida uji, pada umumnya P. xylostella strain Lembang, Pangalengan, Kejajar/Dieng, dan Batu sangatresisten terhadap deltametrin dan profenofos kecuali strain Berastagi tidak diketahui. Semua strain P. xylostella(Lembang, Pangalengan, Kejajar/Dieng, Batu, dan Berastagi) rentan terhadap fipronil dan B. thuringiensis subsp./varkurstaki strain EG 7841. Plutella xylostella strain Lembang, Pangalengan, dan Berastagi sangat resisten terhadap B.thuringiensis subsp./var. kurstaki strain HD-7, sedang P. xylostella strain Kejajar/Dieng dan Batu agak resistenterhadap abamektin. Berdasarkan hasil penelitian ini terbukti, bahwa pemantauan perkembangan resistensi P.xylostella terhadap jenis insektisida yang umum digunakan oleh petani kubis sangat penting dilakukan secara rutin.Hasil penelitian ini juga berguna untuk menyusun data dasar LC50 dan strategi pengelolaan resistensi insektisida.AB STRACT. Moekasan, T.K., S. Sastrosiswojo, T. Rukmana, H. Sutanto, I.S. Purnamasari, and A. Kurnia.2004. Re sis tance study in five strains of Plutella xylostella (L.) to fipronil, delta meth rin, Ba cil lus thuringiensis,profenofos, and abamectin for mu lated prod ucts. The tox ic ity of fipronil, delta meth rin, profenofos, abamectin, Ba -cil lus thuringiensis subsp./var kurstaki strain EG 7841 (crymax WDG), and B. thuringiensis subsp./var. kurstaki strainHD-7 (dipel WP), was as sessed in the lab o ra tory against field strains of di a mond back moth (DBM), Plutellaxylostella (L.) from Lembang, Pangalengan, Kejajar/Dieng, Batu, and Berastagi cab bage grow ing ar eas us ing aleaf-dip bioassay us ing sec ond or third instar lar vae. Re sults in di cated that there were dif fer ences in DBM susceptibilityde pend ing upon their or i gin. In gen eral, Lembang, Pangalengan, Kejajar/Dieng, and Batu DBM strains werehighly re sis tant to delta meth rin and profenofos ex cept for Berastagi DBM strain was un known, based on their LC50val ues. All DBM field strains (Lembang, Pangalengan, Kejajar/Dieng, Batu, and Berastagi) were sus cep ti ble tofipronil and B. thuringiensis subsp./var strain kurstaki EG 7841 (crymax WDG), ex cept for Pangalengan strain in di -cated slightly re sis tant to crymax WDG. Highly re sis tant was shown by DBM strains from Lembang, Pangalengan,and Berastagi to B. thuringiensis subsp./var kurstaki strain HD-7 (dipel WP), and mod er ate re sis tant was shown byDBM strains from Kejajar/Dieng and Batu to abamectin. Re sults from lab o ra tory bioassay sug gest that pop u la tions ofP. xylostella from the cen ters of most veg e ta ble grow ing ar eas have evolved re sis tance to delta meth rin and profenofos,and partly to B. thuringiensis and abamectin. This study also proved that rou tine mon i tor ing on the de vel op ment ofDBM resitance to com monly used of in sec ti cides by cab bage farm ers is very im por tant. Re sult of this study is use ful toes tab lish base line data of LC50 and strategy for insecticide resistance management.