Evaluation of promising cytoplasmic male-sterile line of rice for agronomical and floral traits

Nine CMS lines of rice were evaluated for their morphological and floral traits. six agronomical traits with standard check CMS line IR-58025A. Five CMS lines viz., IR-6888A, HPMS-10A, HPMS-11A, HP-5001A and HP-5004A were of early in duration (75 to 89 days to 50% flowering) and other three lines were of medium duration (90–100 days). HP-5001A was the earliest in days to 50% flowering (75 days); while IR-70362A was late (101 days). The lines viz., IR-70362, IR-70372, HPMS-5A and HPMS-92 recorded, significantly more days to 50% flowering over IR-58025A (check). The maximum plant height was observed in HPMS-9A (105.0 cm) followed by HP-5001A (91.0 cm) and HP-5004A (88.00 cm). The shortest plant height was observed in IR-70362 (65.7 cm). The maximum productive tillers plant⁻¹, observed in HP-5004 (12.0), was significantly superior to the check. The panicle length ranged from 20.0 (HPMS-5A) to 30.0 (HP-5001A) cm. Panicle exertion is an important feature in CMS lines for getting proper seed production. The panicle exertion ranged from 74.60 (IR-70362A) to 90.00 (HP-5001A) percent. The spikelets per panicle were highest in HP-5001A (192.0). The floral characteristics, like stigma exertion was maximum in CMS line IR-6888A (61%) followed by HP-5004A (58.85%) and HP-5001A (51.8%) which were significantly superior to check. Pollen sterility was cent per cent in the line HP-5001A, HP-5004A and IR-58025A. Three CMS lines viz., IR-6888A, IR-70372 and HPMS-5A showed more than 95% pollen sterility and these were categorized under highly sterile CMS lines.