甘肃省农业科学院揭榜挂帅项目(2021GAAS03)；甘肃省重点研发计划(23YFNA0033); 国家自然科学(32060481, 32160471,3 2260485)；中国科学技术协会青年人才托举工程计划(2020QNRC001)
Foundation projects: Open Competition Project of Gansu Academy of Agricultural Sciences (2021GAAS03); National Natural Science Foundation of China (32060481, 32160471, 32260485); Young Elite Scientists Sponsorship Program by the China Association for Science and Technology CAST (2020QNRC001）
Landrace are important germplasm resources for wheat breeding. In order to uncover the distribution of dwarfing genes in landraces, we detected the allelic variation types of dwarfing genes and their distribution frequencies in different wheat regions of Gansu Province. The results showed that: (1) the frequency of Rht-B1b and Rht-D1b in landraces was extremely low. 41.4% of landraces carried Rht8, with higher frequency in spring wheat regions than in winter wheat regions. 46.7% of landraces contained Rht24b, with lower frequency in spring wheat regions than in winter wheat regions. The frequency of Ppd-D1a was only 17.8%, with lower frequency in spring wheat regions than in winter wheat regions. In addition, only three combinations (Rht-D1b/Rht8, Rht-D1b/Rht24b, and Rht8/Rht24b) were detected, with frequencies of 0.2%, 0.5%, and 12.8%, respectively. (2) The frequency and combination distribution of dwarfing genes carried by landraces were lower than those of cultivars, and the differences were significant. Different sources of cultivars carried the same dominant dwarfing allelic variations and frequencies. Qingshui cultivars mainly carried Rht-D1b, Rht8, and Rht24b, Huangyang cultivars mainly carried Rht-B1b, Rht-D1b, Rht8, and Rht24b, and Gangu cultivars mainly carried Rht8 and Rht24b. Qingshui and Huangyang cultivars had dwarf stature and high yield potential, suitable for wheat breeding in Hexi and Yellow River irrigation areas. Gangu cultivars had higher plant height and better disease resistance, suitable for disease improvement in dryland wheat in Dingxi, Tianshui, Longnan, and Longdong, etc. (3) It is speculated that the dwarfing genes of cultivars may come from Nonglin 10 and Akakomugi. (4) Fifteen landraces and 31 cultivars were screened, which can serve as references for dwarfing wheat breeding in different wheat regions of Gansu.