Effect On Outcrossing Characteristics Of Photo Thermo Sensitive Genic Male Sterile(PTGMS) Rice Lines Of Temperature At The Fertility Sensitive Stage

To explore the effects of temperature on Out-crossing characteristics of photo-thermosensitive genic male sterile(PTGMS)line in Rice at Fertility sensitive period.TakingPeiai64 S,Y58S,Guangzhan63-2Sand H638 S as material at the fertility sensitive stage,was treated with five temperature(24℃,27℃,30℃,33℃,36℃)for consecutive 6 days by a phytotron,compared with natural temperature as control(CK,the mean temperature for 29.8℃),the effect of temperature on these sterile lines was studied by physiological and biochemical characteristics of young spike and outcrossing characteristics from heading to flowering stage.The results were as follows:1.The 4 sterile lines were sterile with no stained pollen,and the number of typical pollen was reduced with temperature rising,the most typical pollen at 24℃ and 27℃,whilethe lowest at 36℃ in a phytotron and under the natural conditions.The temperature-sensitivity of these sterile lines showed difference,,the most sensitive to temperature isY58 S,which turned into no pollen type at 33℃ and 36℃,followed by Pei64 S,Guangzhan63-2S and H638 S.2.The temperature treatment,which over 30℃ at the fertility sensitivity stage of 4 sterile lines,was go against to the performance of Out-crossing characteristics,and the performance of the sterile lines were different.The highest stigma exposure rate of 4sterile lines was appeared at 24℃and 27℃,which was significantly higher than other high-temperature treatment(33℃and 36℃);the stigma vigour decreased with the treatment temperature rising,and the highest was appeared at 24℃ and 27℃;the highest out-crossing rate of Pei-64 S,Guangzhan63-2Sand H638 Sat 24℃,which respectively was 58.87%,54.22%,50.5%,was significantly higher than treatment with 33℃ and 36℃,the out-crossing rate of Y58S(58.96%)at 27℃ was the best,which was significantly higher than other treatment;the control temperature(29.8℃)was closely to 30 ℃,but the out-crossing rate at 29.8℃was significantly higher than treatment with 30 ℃.3.The content of MDA in young panicle of four sterile lines increased with the processing temperature rising,and the content at 33℃and36℃ was significantly higher than other treatments and control.the activity of peroxidase(POD)increased then decreased,and the highest of the four sterile lines was appeared at 33℃,which was significantly higher than other treatments and control;Proline content increased with the rise of processing temperature,the content of Proline was highest at 33℃and 36℃,which was significantly higher than other treatments;The soluble sugar content decreased with temperature rising,and remained significantly higher at 24℃and 27℃ than other treatments and control.4.when seed production is used PTGMS,under the assurance of fertility safety,the selection of suitable temperature at the fertility sensitivity stage has important influence on out-crossing characteristics,this study has shown that out-crossing characteristics of the four sterile lines at 24℃and 27℃ is better than other treatment of high-temperature(33℃and 36℃).