Selection to improve germination of shrunken-2 (sh2) sweet corn

English. The objectives of this study were to evaluate the germination of three populations of sh2 sweet corn and to increase the germination of sh2 by indirect selection. Two cycles of selection for improved germination based on seed weight were performed in three populations of shrunken-2 (sh2) sweet corn; Cr13 x Wh2 (pop A), "8925" x 9261" (pop B), and "9070" x 8651" (pop D). This study was conducted on a "plano silt loam", Madison, Wisconsin United States of America from summer 1989 to spring 1991. The original and the two cycle populations were tested for warm and cold germination and one cycle population was tested for field emergence. Cycles were considered as fixed effect and the effect of cycles were analyzed by regression analysis according to the model of Eberhart (1964). Of the three populations selected for weight, population D was more responsive than population A and B. The percentage of warm and cold germination of population D increased approximately 2.0 and 5.6 unit respectively for each cycle of selection. Furthermore, in one cycle of selection for increased weight, field emergence of population A increased significantly compared to population B and D under unfavorable condition. In contrast, field emergence of population A under favorable condition was not significantly different from population B and D

unknown. Tujuan percobaan adalah untuk mengevaluasi daya kecambah benih jagung manis tipe sh2 dan memperbaiki daya kecambah ketiga populasi jagung manis dengan tipe sh2 melalui seleksi tidak langsung. Dua siklus seleksi untuk memperbaiki daya kecambah jagung manis berdasarkan bobot biji dibentuk dari tiga populasi jagung manis tipe shrunken2 (Sh2), yaitu populasi A dari Cr13 x Wh2, populasi B dari "8925" x "9261", dan populasi D dari "9070" x "8651". Percobaan dilaksanakan di Madison, Wisconsin, Amerika Serikat dengan jenis tanah "plano silt loam" mulai musim panas 1989 sampai dengan musim semi 1991. Daya kecambah di laboratorium dilakukan terhadap dua siklus seleksi, sedangkan daya kecambah di lapang dilakukan terhadap satu siklus seleksi. Siklus seleksi dipertimbangkan sebagai pengaruh tetap dan pengaruh siklus seleksi dianalisis dengan metode Eberhart (1964). Dari ketiga populasi yang dicobakan, populasi D menunjukkan tanggapan yang lebih baik dibandingkan dengan populasi A dan B. Persentase perkecambahan populasi D, baik di tempat dingin maupun normal meningkat sekitar 2,0 dan 5,6 unit setiap siklus seleksi berdasarkan bobot biji, persentase perkecambahan populasi A di lapang meningkat dibandingkan dengan populasi B dan D pada kondisi yang buruk ("unfavorable"). Sebaliknya, perkecambahan populasi A pada kondisi optimum di lapang tidak berbeda nyata dengan populasi B dan D