Four sterile lines （Peiai64S, Y58S, Guangzhan 63-2S and H638S） and the restoring line R527 were used as materials. Five temperature gradients （24, 27, 30, 33 and 36 ℃ in artificial climate chamber） and the natural temperature （as control） were treated to the four sterile lines for 6 d in the fertility sensitive period of heading to flowering stage, respectively, to study the effects of temperature on physiological biochemical characteristics of young panicles and outcrossing characteristics. The results showed that the percentages of exerted stigma of Peiai 64S and Y58S were the highest at 27 ℃, which were 86.81% and 86.06%, respectively, while the percentages of exerted stigma of Guangzhan 63-2S and H638S were the highest at 24 ℃, which were 76.24% and 81.76%, respectively; the stigma viability of Peiai 64S, Y58S, Guangzhan 63-2S and H638S were the best at 24 ℃, which were 1.96, 2.12, 1.74 and 1.94, respectively; the outcrossing rates of Peiai 64S, Guangzhan 63-2S and H638S were the highest at 24 ℃, which were 58.87%, 54.22% and 50.50%, respectively, while the outcrossing rate of Y58S was the highest at 27 ℃, which was 58.96%; and the contents of peroxidase （POD） of the four sterile lines increased significantly at 33 ℃ compared with the control, while the contents of malondialdehyde （MDA） and proline increased significantly at 36 ℃ compared with the control. There were differences in temperature sensitivity between the male sterile lines, and the 24 ℃ treatment during the sensitive period was the best for the fertility sensitive period of Peiai 64S, while 27 ℃ was the best temperature for Y58S, Gangzhan 63-2S and H638S.
In order to study the effects of mechanized transplanting and fertilization mode on population growth and development of the male parent in seed production of hybrid rice, three male parents, Huazhan, Shuhui 527 and R9311 were selected as materials. The male parents were transplanted by rice transplanter with two kinds of line spacing design, six lines with equal row spacing （20/25 cm x 30 cm） and wide and narrow spacing （20/25 cm x 40, 20 cm）, and artificial transplanting with equal row spacing （20/25 cm x 30 cm） was set as the control. The three fer- tilization modes were applying for one, two and three times. The flowering stage and panicle-spikelet structure of the male parent were investigated. The results showed that the effects of mechanized transplanting and fertilization mode were little on the duration from seeding to heading; the panicles and spikelets of the three male parents were significantly increased by mechanized transplanting. The tiller number was increased by mechanized transplanting and fertilizing for two and three times. Wide and narrow spacing by machine planting and fertilizing for three times were suitable for Huazhan, which significantly increased the number of spikelets per unit area. Furthermore, the number of spikelets per unit area of Shuhui 527 and R9311 were significantly increased by mechanized transplanting and fertilizing for three times.
