Tingkat Resistensi Lipas Jerman (Blattella germanica L.) asal Tiga Pasar di Kota Purwokerto terhadap Fipronil Menggunakan Metode Kontak dan Umpan: Resistance Level of German Cockroaches (Blattella germanica L.) Origin of Three Traditional Markets in Purwokerto City to Fipronil

German cockroaches in Indonesia have developed resistance to various insecticides. Although cases of german cockroach resistance have been reported in several areas in Indonesia, there have been no reports of such resistance cases in Purwokerto. The specific purpose of this study was to determine the resistance status of german cockroaches from three traditional markets (pasar) in Purwokerto to fipronil. The method used was the contact and bait method, using ten male cockroaches and repeated five times for each strain. The data obtained were analyzed using probit analysis to calculate the time of death (Lethal Time), and then the resistance level was calculated. The results showed that the time of death (LT50) for field cockroaches using the contact method, the highest resistance level was obtained from the Pasar-1 strain with an LT50 value of 3.05 hours, while the lowest was in the Pasar-3 strain with an LT50 value of 1.83 hours. In testing with the bait method using gel bait containing 0.03% fipronil, the LT50 value of cockroaches from Pasar-1 was 14.16 hours, while cockroaches from Pasar-3 had an LT50 value of 8.02 hours. The resistance ratio value (RR50) calculation showed that all cockroaches from three traditional markets in the city of Purwokerto did not show resistance to fipronil which was tested with the resistance ratio value of all field strains below 1. Susceptible to insecticides with the active ingredient fipronil. The active ingredient fipronil in bait formulations may be used for monitoring and control of German cockroaches. Abstrak. Lipas jerman telah resisten terhadap berbagai macam insektisida, dibuktikan dengan adanya kasus resistensi lipas jerman yang dilaporkan terjadi di beberapa wilayah di Indonesia. Meskipun demikian, di wilayah Kota Purwokerto sampai saat ini belum ada laporan mengenai kasus resistensi tersebut. Tujuan khusus penelitian ini adalah mengetahui status resistensi lipas jerman dari tiga pasar tradisional yang ada di Kota Purwokerto terhadap fipronil. Metode yang digunakan adalah metode kontak dan umpan dengan menggunakan sepuluh ekor lipas jantan dan diulang lima kali untuk masing-masing strain. Data yang diperoleh dianalisis menggunakan analisis probit untuk menghitung waktu kematian (Lethal Time), untuk kemudian dihitung tingkat resistensinya. Hasil penelitian menunjukkan bahwa waktu kematian (LT50) lipas lapangan menggunakan metode kontak pada tingkat resistensitertinggi adalah dari strain Pasar-1 dengan nilai LT5