Mutation breeding in sorghum (Sorghum bicolor L.) for improving plants as ruminant feed

英语. Mutation breeding using gamma irradiation in sorghum was aimed at improving the quality and production of sorghum plants as ruminant feed. Seeds of local sorghum variety "Keris" with moisture content of about 14 percent were irradiated with gamma rays from Cobalt-60 source using the dose levels up to 0.5 kGy. The M1 plants were grown in Pasar Jumat, the M2 and M3 were grown in Citayam experimental station. The M2 plants were harvested 40 days after sowing by cutting plants 20 cm above ground surface. Two weeks later observations were done for the ability of plants to produce new buds (bud variable). The plants green products in form of their dry weight (product variable) were collected 40 days after harvesting and drying process in oven at 105 deg. C for 24 hours. Plant selections with intensity of 20 percent were done for the bud variable among samples of M2 plants. Selection responses in the M3 were found to vary from the lowest at 0.5 kGy population (Rs = 0.2116) to the highest at 0.3 kGy population (Rs = 0.8507). The share of genetic factors to selection responses in bud variable varied from 7.25 percent at 0.5 kGy population to 22.35 percent at 0.3 kGy population. Selection for bud variable gave directly a positive impact in increasing product variable in the M3

印度尼西亚. Pemuliaan mutasi dengan iradiasi gamma pada tanaman sorghum ditujukan untuk perbaikan kualitas dan produksi tanaman sebagai pakan hijauan ternak ruminansia. Benih sorghum lokal varietas "Keris" dengan kadar air +- 14 persen diiradiasi dengan sinar gamma bersumber dari Cobalt-60 dengan dosis sampai dengan 0,5 kGy. Tanaman M1 ditumbuhkan di kebun percobaan Pasar Jumat, tanaman M2 dan M3 di kebun Citayam. Pada umur 40 hari setelah tanam, tanaman M2 dipanen/dipangkas setinggi 20 cm dari permukaan tanah. Dua minggu kemudian pengamatan dilakukan terhadap variabel sifat kemampuan tanaman membentuk tunas baru (variabel tunas). Data produksi hijauan dalam bentuk bobot kering (variabel produksi) dikumpulkan setelah tanaman dipanen pada umur 40 hari setelah pemangkasan dan dipanaskan dalam oven 105 derajat C selama 24 jam. Seleksi tanaman dengan intensitas 20 persen dilakukan terhadap variabel tunas pada sampel tanaman M2. Respon seleksi pada M3 bervariasi mulai terendah pada populasi 0,5 kGy (Rs = 0,2116) sampai tertinggi pada populasi 0,3 kGy (Rs = 0,8507). Sumbangan faktor genetik terhadap respon seleksi bervariasi mulai dari 7,25 persen pada populasi 0,5 kGy sampai 22,35 persen pada populasi 0,3 kGy. Seleksi terhadap variabel tunas secara langsung telah memberikan dampak positif pada peningkatan variabel produksi di M3