关键词: 小麦, 光温敏雄性不育系, 温差, 育性转换

Abstract:

BS type photo-thermal sensitive male sterile line is the core of the application of two-line hybrid wheat. Five BS type male sterile lines and a conventional variety Jing 411 were studied to investigate the relationship of the fertility with temperature difference for improving hybrid wheat seed production and propagation of the male sterile lines. We studied the safe seed production and propagation sowing date of sterile lines with differentially sowing tests and controlled experiments in growth chambers. Under the different temperature difference conditions, we compared the differences in fertility and agronomic traits of male sterile lines, and further analyzed the correlation between temperature difference and seed-setting rate and agronomic traits. The results showed the safe sowing dates of the sterile line BS185 was from October 10th to 20th, BS135 was from October 15th to 20th, and BS102, BS107 and BS278 were October 20th in the sterile line breeding area in Shunyi, Beijing. The safe sowing dates of five sterile lines with high sterility were from October 5th to 25th, which could be safe for seed production, and the safe seed production sowing dates of BS102 and BS107 could reach October 30th in the sterile line seed production area in Dengzhou, Henan. Under the different conditions of 12 h 12 ℃, BS102 and BS135 were less affected by temperature difference, and the safety of seed production was better. BS107 and BS185 could produce seeds safely at the temperature difference of 10 and 15 ℃, and safe seeds production of B278 could be achieved at the temperature difference of 5, 10 and 15 ℃. Seed-setting rate had negative correlations with temperature difference. Furthermore, plant height and spike length had positive correlations with temperature difference. Under the different conditions of 14 h 16 ℃, BS102 and BS278 were less affected by temperature difference, BS107, BS135 and BS185 were greatly affected by temperature difference, and could effectively breed at the temperature difference of 10 and 15 ℃. Seed-setting rate had positive correlations with temperature difference, plant height of most male sterile lines had positive correlations with temperature difference. Therefore, raising the temperature difference was more conducive to the safe seed production and efficient seed propagation of the sterile lines.

Key words: Wheat, Photo-thermal sensitive male sterile lines, Temperature difference, Fertility alteration