Herbicide Resistance Traits of Zhongjing 616 Improved by Backcrossing

The use of herbicides would reduce the yield and quality of rice. It was urgent to improve the non-transgenic herbicide-tolerant rice varieties. Zhongjing 616 (receptor material) and the herbicide-tolerant varieties, such as Jinjing 818 and Jingtian Meizhan, were selected as the experimental materials, and the concentration gradient test of herbicide (Xianda Doushile, 5% imidazoic acid content) was used to screen the herbicide-tolerant treatment concentrations. Zhongjing 616-TR was obtained through the hybridization, backcrossing and self-crossing combined with the screening of herbicide resistance. The effects of herbicides on the seedling germination and growth of the improved Zhongjing 616-TR were further analyzed. At the same time, Zhongjing 616 was used as the control group to carry out the variety comparison test. The results showed that the herbicide concentration gradient experimentation results showed that 3 mL·L^-1 could be used as the follow-up screening concentration of herbicide-tolerant rice. The improved Zhongjing 616-TR was resistant to herbicides at the germination stage and the seedling stage when treated with 3 mL·L^-1 herbicide. The variety comparison test showed that there was no significant difference in the agronomic traits, yield, disease resistance and quality between Zhongjing 616-TR and Zhongjing 616. In summary, the improved Zhongjing 616-TR had the characteristics of excellent quality, good rice blast resistance, high yield and herbicide resistance.