An investigation was carried out with three newly developed temperature sensitive genic male sterile （TGMS） lines for their floral traits, seed production potential and outcrossing ability in ten cross combinations....An investigation was carried out with three newly developed temperature sensitive genic male sterile （TGMS） lines for their floral traits, seed production potential and outcrossing ability in ten cross combinations. In the TGMS lines, fertile pollens had an average diameter of 0.89 mm while the sterile pollens was with 0.02 mm diameter.TS-29-150GY produced the biggest fertile pollens with 0.92 mm and other two lines produced relatively smaller pollens with 0.91 and 0.85 ram. Pollen fertility during the fertility reversion period was an average of 60.7%. TS-29-150GY had the maximum of 66.9% spikelet fertility whereas other two lines （TNAU18S and TNAU60S） had relatively lower spikelet fertility of 27.8% and 26.7%, respectively. Average of 17.00 g of seed yield was obtained in the TGMS lines during the fertility reversion period. TS-29- 150GY had the highest value of 21.20 g of seed yield while TNAU18S and TNAU60S produced 16.6 g and 13.2 g of seed yield, respectively. The low seed production ability of these three TGMS lines was attributed only to the environmental conditions prevailing during the period. All three TGMS lines had considerable outcrossing potential of 41.2%, 24.6% and 25.0%, respectively. The cross combinations viz. TNAU18S/IET21508 （36 g/plant）, TNAU18S/IET21044 （13 g/plant）, TNAU18S/IET21009 （26.5 g/plant）, TNAU60S/CB-09-106 （26.2 g/plant）, TNAU60S/IET21009 （14 g/plant） and TS29-150-GY/DRR 3306 （39.2 g/plant） showed perfect synchronization with acceptable hybrid seed yield, indicating suitability of TGMS system under Indian condition. Based on the outcrossing related traits viz. panicle exertion, angle of glume opening, stigma length and pollen size, TNAU18S was identified as the best, followed by TS-29-150GY.展开更多
By using the methods of semi thin and thin section, the process of pollen development was comparatively studied in Peiai 64S, a photoperiod temperature sensitive genic male sterile line (PTGMS) and IR36, a fertile cul...By using the methods of semi thin and thin section, the process of pollen development was comparatively studied in Peiai 64S, a photoperiod temperature sensitive genic male sterile line (PTGMS) and IR36, a fertile cultivar in rice. The development of Peiai 64S and IR36 did not differ up to microsporocyte formation stage; but since meiosis stage, male reproductive cells of Peiai 64S underwent several structural changes and ultimately terminated by early bicellular stage. These abnormal changes mainly occurred at two stages: (1) at meiotic prophase, almost half of Peiai 64S microsporocytes exhibited aberration, with sparse free ribosomes, underdeveloped mitochondria and many swollen endoplasmic reticula. These abnormal cells became dramatically vacuolated and hereafter disintegrated completely at later stage. (2) After the early uninucleate stage, nearly all of Peiai 64S microspores possessed malfunctional exine that was deviod of electron transparent region between sexine and nexine, and no intine was established. But, the development and disintegration of tapetum in Peiai 64S resembled those of IR36. The results proposed that the abnormalities of microsporocytic cytoplasm or pollen exine, rather than the tapetal development caused the pollen abortion of Peiai 64S.展开更多
文摘An investigation was carried out with three newly developed temperature sensitive genic male sterile （TGMS） lines for their floral traits, seed production potential and outcrossing ability in ten cross combinations. In the TGMS lines, fertile pollens had an average diameter of 0.89 mm while the sterile pollens was with 0.02 mm diameter.TS-29-150GY produced the biggest fertile pollens with 0.92 mm and other two lines produced relatively smaller pollens with 0.91 and 0.85 ram. Pollen fertility during the fertility reversion period was an average of 60.7%. TS-29-150GY had the maximum of 66.9% spikelet fertility whereas other two lines （TNAU18S and TNAU60S） had relatively lower spikelet fertility of 27.8% and 26.7%, respectively. Average of 17.00 g of seed yield was obtained in the TGMS lines during the fertility reversion period. TS-29- 150GY had the highest value of 21.20 g of seed yield while TNAU18S and TNAU60S produced 16.6 g and 13.2 g of seed yield, respectively. The low seed production ability of these three TGMS lines was attributed only to the environmental conditions prevailing during the period. All three TGMS lines had considerable outcrossing potential of 41.2%, 24.6% and 25.0%, respectively. The cross combinations viz. TNAU18S/IET21508 （36 g/plant）, TNAU18S/IET21044 （13 g/plant）, TNAU18S/IET21009 （26.5 g/plant）, TNAU60S/CB-09-106 （26.2 g/plant）, TNAU60S/IET21009 （14 g/plant） and TS29-150-GY/DRR 3306 （39.2 g/plant） showed perfect synchronization with acceptable hybrid seed yield, indicating suitability of TGMS system under Indian condition. Based on the outcrossing related traits viz. panicle exertion, angle of glume opening, stigma length and pollen size, TNAU18S was identified as the best, followed by TS-29-150GY.
文摘By using the methods of semi thin and thin section, the process of pollen development was comparatively studied in Peiai 64S, a photoperiod temperature sensitive genic male sterile line (PTGMS) and IR36, a fertile cultivar in rice. The development of Peiai 64S and IR36 did not differ up to microsporocyte formation stage; but since meiosis stage, male reproductive cells of Peiai 64S underwent several structural changes and ultimately terminated by early bicellular stage. These abnormal changes mainly occurred at two stages: (1) at meiotic prophase, almost half of Peiai 64S microsporocytes exhibited aberration, with sparse free ribosomes, underdeveloped mitochondria and many swollen endoplasmic reticula. These abnormal cells became dramatically vacuolated and hereafter disintegrated completely at later stage. (2) After the early uninucleate stage, nearly all of Peiai 64S microspores possessed malfunctional exine that was deviod of electron transparent region between sexine and nexine, and no intine was established. But, the development and disintegration of tapetum in Peiai 64S resembled those of IR36. The results proposed that the abnormalities of microsporocytic cytoplasm or pollen exine, rather than the tapetal development caused the pollen abortion of Peiai 64S.
