The influence of gamma rays irradiation on chlorophyll mutation and genetic variability of resistance to blast disease in upland rice

英语. Seeds of Danau Tempe and line of B-3268-Tb were irradiated with 0.10; 0.15; 0.20; and 0.25 kGy 60C0. Number of irradiated seeds for each treatment was 1000 seeds and the moisture content was about 12.5 percent. The M1 generation plants were grown in the field during dry season of 1993 at Pasar Jumat. One panicle of each M1 plants was harvested and 200 panicles of each treatment were planted as M2 generation plant in Tamanbogo Field Experiment at Lampung in wet season of 1993/1994. Ten days after planting the number of M2 plants and the number of chlorophyll mutations were recorded. Inoculation of Pyricularia oryzae Cav blast disease was conducted by natural infection. The symtomps of leaf blast and neck blast diseases were observed at 60 and 110 days after germination, respectively. The genetic variability and coefficient of variability value of M2 plants resistant to blast were estimated. The results showed that chlorophyll mutations, the genetic variability, and the heritability value of plants resistant to blast disease can be improved by gamma irradiation of 0.10-0.25 kGy

印度尼西亚. Benih padi gogo kultivar Danau Tempe dan galur B-3268-Tb diiradiasi sinar gamma dari 60 Co dengan dosis 0.10; 0.15; 0.20 dan 0.25 kGy. Jumlah benih yang diiradiasi sebanyak 1000 butir setiap dosis dengan kadar air 12.5 persen. Tanaman M1 ditanam di pasar Jumat pada musim tanam MK 1993. Setiap tanaman M1 dipanen satu malai dan ditanam di Kebun Percobaan Tamanbogo, Lampung sebagai tanaman M2 dan jumlah mutasi khlorofil dihitung. Inokulasi penyakit blas Pyricularia oryzae Cav dilakukan secara alami. Gejala serangan penyakit blas daun dan blas leher malai diamati pada umur 60 hari dan 110 hari setelah tumbuh. Variasi dan koefisien variasi genetik tanaman M2 yang tahan penyakit blas dan nilai heritabilitas ketahanannya dihitung. Hasil penelitian menunjukkan bahwa iradiasi sinar gamma dengan dosis 0.10-0.25 kGy dapat meningkatkan mutasi khlorofil dan variasi genetik ketahanan terhadap penyakit blas