Development Of Rice Photo-thermo-sensitive Genic Male Sterile Lines On The Genetic Background Of 9311

Rice (Oryza sativa L.) is a staple crop in the world and consumed by more than 60% people of China as their main food. Although China's paddy rice breeding is in the world leading position, there is a huge pressure because of the growth of population and climate changement. Extensive spread of two-line hybrid rice was an outstanding contribution and had a positive effect on food safety of China even all over the world.9311 and photo-thermal sensitive genic male sterile (PTGMS) line Peiai64S were used as recipient, and donor respectively, to develop 7 novel two-line sterile lines, including Hua553S, Hua554S, Hua557S, Hua559S, Hua573S-1, Hua574S-3 and Hua575S in this study. These developed sterile lines owned similar main agronomic traits with 9311 and novel sterile flowering habit The characteristics of fertility alternation were also identified. Those PTGMS lines were used as female parents for crossing two set male parents by NCⅡdesign, their F1 hybrids were investigated and analyzed for yield and main agronomic traits in 2009 and 2010 at Wuhan.The main results are as follows:1. Seven male sterile lines were investigated for their developmental characters and the main agronomic traits in 2008 and 2009 under field natural conditions at Wuhan. The growth period of Hua559S and Hua553S was the longest, shortest respectively;plant height of Hua575S and Hua553S was the highes, shortest respectively; grain density of Hua554S and Hua559S was highest, lowest respectively.2. Seven male sterile lines were investigated for their fertility performance in2008 and 2009 under field natural conditions at Wuhan.The best stability of fertility performance were Hua553S and Hua557S,the other five male sterile lines were instability. All the seven male sterile lines were sensitive to temperature.3. The developmental stages about sensitive to temperature and photoperiod were different among seven male sterile lines. But The developmental stages about sensitive to temperature and photoperiod among seven male sterile lines were 18 days or so.Hua557S and Hua574S-3 were the most obvious.That of Hua573S-1 was 16-24 days.4. The flowering time of 7 lines are centralized,60% of sterile lines flowed before midday; Hua554S showed the highest stigma exsertion rate,63.46% and the lowest rate of bract panicle,7.82%; Hua573S-1 showed the largest distance of opened glume tips of 4.5 mm; Hua553S showed the largest spikelet opening angle 31.80; Hua554S had the longest spikelet opening time.5. General combining ability and special combining ability of most traits showed significant difference for tested sterile lines. The additive effect predominates to non-additive effect on most of the traits. There is no significant correlation between general combining ability of parents and special combining ability of hybrids.