Mutasi pada Beberapa Kandidat Galur Mutan Pemulih Kesuburan Tanaman Padi

Cytoplasmic male sterility (CMS) system has largely been applied in development of rice hybrid varieties. In this system the maintainer and restorer lines are necessary to maintain the CMS and to restore the pollination abilities of hybrid plants, respectively. In this study, rice candidate of restorer mutant lines were developed through irradiation of CMS seeds by 0.2 kGy gamma rays. Some mutations indicated by polymorphism between mutants and original plants were observed through simple sequence repeat (SSR) marker genome survey in six mutant lines. Frequencies of polymorphism varied depend on the lines, range from 8.5 to 18.3%. No common marker showed polymorphism between six mutant lines and original plants indicating that the mutant lines do not carry the same restoring genes. Nevertheless, allelic tests or linkage studies using segregating populations are needed for confirmation. This result should be useful as initial information on genetic studies of restoring genes induced by gamma ray irradiation as well as for application of these genes in hybrid rice breeding program

Identification and Mapping of a Gene for Rice Slender Kernel Using Oryza Glumaepatula Introgression Lines

World demand for superior rice grain quality tends to increase. One of the criteria of appearance quality of rice grain is grain shape. Rice consumers exhibit wide preferences for grain shape, but most Indonesian rice consumers prefer long and slender grain. The objectives of this study were to identify and map a gene for rice slender kernel trait using Oryza glumaepatula introgression lines with O. sativa cv. Taichung 65 genetic background. A segregation analysis of BC4F2 population derived from backcrosses of a donor parent O. glumaepatula into a recurrent parent Taichung 65 showed that the slender kernel was controlled by a single recessive gene. This new identified gene was designated as sk1 (slender kernel 1). Moreover, based on the RFLP analyses using 14 RFLP markers located on chromosomes 2, 8, 9, and 10 in which the O. glumaepatula chromosomal segments were retained in BC4F2 population, the sk1 was located between RFLP markers C679 and C560 on the long arm of chromosome 2, with map distances of 2.8 and 1.5 cM, respectively. The wild rice O. glumaepatula carried a recessive allele for slender kernel. This allele may be useful in breeding of rice with slender kernel types. In addition, the development of plant materials and RFLP map associated with slender kernel in this study is the preliminary works in the effort to isolate this important grain shape gene

Induksi Kalus Dan Regenerasi Tanaman Dari Kultur Antera Padi Fl Hybrid (Oryza Sativa L.) * [Callus Induction and Plant Regeneration From Anther Cultures of Rice Hybrid Fl (Oryza Sativa L.)]

A haploid breeding program was initiated to develop doubled haploid blast tolerance rice breeding via anther culture.Blast tolerant variety (Laka) was crossed with Kencana Bali (sensitive to blast).Anthers from F1 were cultured on two kind of media (combination of N6 macro salt and MS micro salt) containing 1 mg/l NAA + 0,1 mg/l kinetin called medium-1 and another one containing 1 mg/l 2,4-D + 0,1 mg/l kinetin called medium-2.Anthers were treated with cold shock (4 °C)for 5 and 10 days before cultured.Results of experiment showed that F1 plants derived anthers were able to form call Number ofplantlets were produced during anthers culture consisted of 482 green plants and 50 albinos. Most of green plants did not produced root.Root growth of plantlets were induced with 1.5-4.5 mg/l IBA in MS medium