摘要：ABSTRACT This study aimed to examine the effect of extract of purwoceng Pimpinella alpina for masculinization of Betta splendens. This research used completely randomized design with three treatments that were distinguished by doses of purwoceng extract, which were 10, 20, and 30 µL/L, and 0 µL/L as control. The treatments were given by immersion to 35 embryos at eye spots phase or about 28-hours after fertilization, for eight hours. The immersion process was done for 8 hours. The result showed that 20 µL/L dose of purwoceng extract produced 62.66% male, and hatching rate was 85.71%. This male percentage was higher compared to control (45.91%), but the hatching rate was lower than that of control (98.57%). At the higher dose (30 µL/L), male fish population and hatching rate reduced respectively 39.72% and 68.57%, respectively. Keywords: masculinization, embryo immersion, purwoceng extract, Betta splendens ABSTRAK Penelitian ini bertujuan untuk mengevaluasi pengaruh dosis ekstrak purwoceng Pimpinella alpina extract dalam maskulinisasi ikan cupang hias Betta splendens. Penelitian ini menggunakan metode rancangan acak lengkap dengan tiga perlakuan dan tiga ulangan dosis ekstrak purwoceng. yaitu 10, 20, dan 30 µL/L, serta perlakuan 0 µL/L sebagai kontrol. Perlakuan diberikan melalui perendaman selama delapan jam terhadap 35 embrio saat memasuki fase bintik mata atau sekitar jam ke-28 setelah pembuahan. Hasil penelitian menunjukkan bahwa dosis ekstrak purwoceng 20 µL/L menghasilkan persentase ikan jantan sebesar 62,66%, dan daya tetas telur sebesar 85,71%. Persentase jantan tersebut lebih tinggi daripada kontrol (45,1%), tetapi derajat penetasannya lebih rendah daripada kontrol (98,57%). Pada dosis yang lebih tinggi (30 µL/L), populasi ikan jantan (39,72%), dan derajat penetasan (68,57%) adalah menurun. Kata kunci: maskulinisasi, perendaman embrio, ekstrak purwoceng, Betta splendens
