Evaluation of improved rice CMS lines according sterility, fertility and allogamy characteristics (Oryza sativa L.)

In the hybrid rice production Technology, selecting the favorite lines based on allogamy characters and increase of A lines seed is necessary. Anther lenght, panicle exesrtion, pollen sterility, stamen filaments length, stigma length, glum length and floret number is important traits of the male sterile lines. Therefore the study of seven cytoplasmic male sterility lines (release from IRRI) their maintenance and 33 male sterility lines derived of backcross (release from Iran) using was randomized complete block design. Anther lenght, panicle exesrtion, pollen sterility, stamen filaments length, stigma length, glum length, floret length, floret width, pollen fertility, panicle length, panicle exsertion rate, percentage of allogamy, Days to flowering were evaluated. The results of pollens sterility indicated that the 4 CMS lines, Neda A, Nemat A, Shastak Mohammadi A and Gerde A were completely sterile. Induction of sterile cytoplasm has led to partial exsertion of panicles. Mean comparison of traits showed that male sterile line of Hasani AR has the longest length of stigma (2.93 mm) and shortest length of anther (1.87 mm), respectively. But out crossing percentage of this was very low. Also, IR69224A showed complete sterility, with out-crossing percentage of x = %37.79. Pollen sterility, number of florets per panicle, legume and stamen length traits has been high genotypic coefficient of variation, inheritance, genetic progress. These traits can be as selection criteria of cytoplasmic male sterility lines with out crossing rate high. Dasht A (dasht × IR68899A), Khazar A, Hasani A, Gerde A, Sang tarom A, Shastak mohammadi A with their maintainer lines were categorized in different groups. Results of this research can be suitable for parental selection and hybrid rice production program.