Evaluation Of Resistance To Rice False Smut And Rice Blast, And Agronomic Characters Evaluation Of Rice Materials Of Breeding Restorer Line

In recent years, with the popularization of hybrid rice and the adoption of measures to increase its production, rice false smut caused by Ustilaginoidea virens (Cook) Takahashi has become the main disease of rice. Meanwhile, rice blast caused by Magnaporthe grisea (Hebert) Barr. is one of the most popular plant diseases. Rice crops are frequently infected by both of them all over the world. It has been proved that cultivating disease-resistant cultivars is the most effective, economical, and environmental-friendly way to control these diseases. Screening and utilization of disease-resistant to false smut and blast is the basic measure to breed resistant varieties. The resistance of380rice materials to rice false smut and rice blast and their main agronomic traits of breeding restorer line were evaluated in this paper. Resistance to rice false smut of98rice materials was evaluated by inoculating mixed strains of Ustilaginoidea virens. Moreover,12rice CMS Lines were crossed with HF2013and then12F1testcross combinations were created, whose resistance and main agronomic traits were evaluated, and the hybrid competitive advantage was also analyzed.1. In380rice materials of breeding restorer line,278rice materials showed high resistant to rice false smut,66showed resistant,26showed middle resistant,10showed medium sensitive to rice false smut. On the other hand,264rice materials showed resistant to panicle blast,109rice materials showed panicle blast Level0. There were201rice materials displaying high resistant to both rice false smut and rice blast, such as HF2007, HF2013, etal, which added up to52.9%of all the rice materials.2. In the98rice materials, there was no significant difference between the inoculated samples and the natural ones. For the inoculated samples and the naturals ones, the disease spike rates were0.0%-20.00%and0.0%～13.24%, respectively, while the disease index were0～13.3and0-8.53, respectively. The material that showed the most serious disease is HF2097. The disease spike rates were20%and13.24%, respectively, while the disease index were11.11and8.53.3. The results showed that there was abundant genetic diversity in67rice materials. The height of the rice ranged from97.60cm to128.50cm, and the average height was111.24±5.32cm. The length of the spike ranged from21.0cm to39.5cm, and the average length was24.7±2.40cm. The effective spike number per plant ranged from5.5to12.7, and the average was9.3±1.46. The weight of a thousand seeds ranged from24.95g to41.48g, and the average was31.66±3.90g. The grain number per spike ranged from103.00to260.43, and the average was158.60±39.48. The effective grain number per spike ranged from85.04to196.62, and the average was120.65±25.25. The seed setting rate ranged from59.08%to92.00%, and the average was77.17±8.24%. The weight of the seed per plant ranged from16.62g to35.39g, and the average was22.16±3.06g.4. Among Fl testcross combinations, there were3sets of H09, H15, and H16, showing resistance to rice false smut. The remaining9sets of samples had Level0of rice false smut, showing high resistance to the disease. Among12samples for panicle blast Level I, there were four sets of H06, H08, H10, and H15. The remaining8sets of samples had Level0of panicle blast, and there were12sets of samples showing resistant to the disease. Results demonstrated that H11, H13, H14, H17, and H18in rice materials of breeding restorer line showed simultaneous high resistance to both rice false smut and panicle blast.5. Compared to Gangyou725,12sets of combination from HF2013were obtained that displayed advantages in agronomic traits. The competitive edge in the height of the rice ranged from6.5cm to3.2cm. There were8combinations including H06and H10that showed725%lower height than Gangyou725. The competitive edge in the length of the spike ranged from-4.00cm to1.09cm. There were10combinations including H06、 IH09that showed lower length than Gangyou725. The competitive edge in the effective spike number per plant ranged from-2.7to-0.7. There were12combinations that showed lower effective spike number per plant than Gangyou725. The competitive edge in the weight of a thousand seeds ranged from2.82g to7.03g. There were12combinations that showed higher dry weight than Gangyou725. The competitive edge in the grain number per spike ranged from-59.77to3.09. There were12combinations that showed lower grain number per spike than Gangyou725. The competitive edge in the effective grain number per spike ranged from-27.25to10.68. There were8combinations that showed lower effective grain number per spike than Gangyou725. The competitive edge in the seed setting rate ranged from-8.89g to2.32g. There were11combinations that showed lower seed setting rate than Gangyou725. For1178A/HF2013that displayed the highest level of competitive advantage, the weight of the seed was34.17g, the effective spike number per plant was8.6, the weight of a thousand seeds was30.33g, the effective grain number per spike was163.95, and the seed setting rate was79.92%.