Abstract:
In recent years, the frequency of extreme weather events such as drought, rainstorm, low temperature and high temperature is increasing, which has a serious impact on wheat production, yield and quality. The total global wheat production in 2023 was 780 million tons, a 3% decrease from the historical highest level in 2022 according to data from the Food and Agriculture Organization of the United Nations. With the rapid development of China's socio-economic and population growth, the demand for wheat in our country is constantly increasing. Therefore, cultivating wheat varieties with high yield, excellent quality, and strong resistance is crucial for national food security. To cultivate new wheat varieties with strong resistance to adversity and a wide range of adaptability for serving the national food security, wheat variety ‘Xiaoyan 22’ was used to radiate with lethal dose of CO
2 laser to found mutant lines. Selection uniform wheat seeds, and then soaking seeds with sterile water for 30min and absorbing surface water with filter paper. Taking 60 seeds and laying them single-layer on the central part of the sample processing platform of the CO2 laser (
Figure 1). Turn on the CO2 laser (developed by the Department of Physics at Northwestern University) to irradiate the seeds for 10 minutes with Power density 20 mW ∙ mm
– 2. We screened the mutant line, and tested its stability, analyzed its yield and quality, and discussed its cultivation techniques. The results showed: (1) 660K gene chip showed that there were 630517 SNP (Single Nucleotide Polymorphisms) loci between ‘Bailu 181’ and ‘Xiaoyan 22’. No difference SNPs were 442 859, which proportion was about 70.23%. differential SNP loci were187657, accounting for 29.76%. Compared with ‘Xiaoyan 22’, genic mutation was mainly occurred on SNPs of AA, CC, CG and TT, which was of 19.23%, 23.50%, 24.40% and 19.46%, respectively. (2) The1000-rain weight and yield of ‘Bailu 181’ were significantly greater than those of ‘Xiaoyan 22’, which mean value of 3 years were of 9.31% and 5.07% higher than that of ‘Xiaoyan 22’. (3) The 17 amino acids in ‘Bailu 181’ seeds were significantly higher than that of ‘Xiaoyan 22’. Compared with ‘Xiaoyan 22’, grain bulk density and wet gluten index increased with 7.33% and 15.40, stability time extended by 11.00% and maximum tensile resistance increased by 34.80%, respectively. (4) Different fertilization and sowing amount have different degrees of impact on the number of grains per spike, thousand grain weight, number of spikes and yield of ‘Bailu 181’. Taking into account both yield and thousand grain weight, maximizing the economic benefits of sowing 180 kg of seeds per hectare under the condition of applying 750 kg of nitrogen fertilizer per hectare. The results showed that ‘Bailu 181’ was more suitable for planting in Guanzhong Plain and the middle reaches of the Yellow River region. About 30% of the genes in ‘Bailu 181’have changed, which provided breeding materials for enriching China's wheat germplasm resources and breeding high-quality and high-yield new varieties.