Evaluation of Sterility Stability for Some of Rice Cytoplasmic Male Sterile Lines

Evaluation of sterility stability between male sterile lines for favorite lines selection is necessary to production of hybrid rice program. So that in present research utilization of 7 cytoplasmic male sterile lines (A line) and 33 male sterile lines product of 7th backcrosses of Iranian varieties with IRRI standard male sterility lines. Experiment was based on a split plot to time design in RCBD. Results of variance analysis showed significant line × time interaction for pollen sterility and panicle at 5% level. Pollen sterility means comparison indicated that five varieties Nemat، Shastak mohammadi، Gerde، Hasani rishak ghermez and Khazar in all crosses with standard lines showed complete sterile in 9 evaluation stages and allocated as completely sterile and stable lines that can be used as sources for transforming sterility genes into new varieties. Pollen and panicle sterility percent of means comparison indicated that Hasani A line despite bearing complete sterility in four stages (3، 10، 17، 7 to 14)، have partial fertility in three stages (6، 6، 7 in greenhouse) and have been maximum seed production percentage (25. 67%) in 2 initial stages of plant. seed production percentage of IR68899A line that shown the most sterility in all stages was 15. 67% at high temperature (> 24c°) and low light (< 13. 75 h) conditions in greenhouse. Therefore، could be utilized for two line hybrid programs.