Characterization of Thermo Sensitive Genetic Male Sterile Lines for Temperature Sensitivity, Morphology and Floral Biology in Rice (Oryza sativa L.)

摘要

Thermo sensitive genetic male sterile lines were screened for temperature sensitivity and their morphology and floral biology were studied. All the six TGMS lines clearly showed a tendency of transformation from sterile to fertile phase, when temperature was decreased in the field as well as under growth chamber conditions. Fertility restoration was more at lower temperature (28/21°C and 24/21°C) for all the six TGMS lines. All the TGMS lines exhibited critical sterility point at temperature more than 30°C. Critical sterility point ranged from 30°C (DRR IS) to 35.9°C (IR 73827-23S). For all morphological traits except ligule shape variation was observed. Floral biology both in sterile and fertile phase showed varied behavior. In sterile phase the time of anthesis ranged from 9:05AM to 9:40 AM. For duration of anthesis there was clear cut difference among the TGMS lines. DRR 5S took minimum time (165 min) and UPRI95-140S (270 min) took maximum time. Blooming duration varied from two to four days. Angle of gloom opening ranged from 25 to 36°. DRR 5S showed less exerted stigma (25%). High stigma exertion was observed in UPRI 95-167S (70%). Out crossing ranged from 20 to 41%. Maximum out crossing rate was recorded in DRR IS. In fertile phase time of anthesis ranged from 9:35 AM to 10:30 AM. Duration of anthesis varied from 140 min in DRR 5S to 215 min in UPRI 95-67S. Blooming duration varied from 3-7 days. Angle of glume opening ranged from 15 to 25°. Stigma exertion was highest in UPRI 95-167S (62.4%) and lowest in DRR 5S (20%).