New Breakthrough In Genetic Research Of Xinjiang Cultivated Land And Cotton

With the high yield of upland cotton and long fiber of island cotton, how the two kinds of cotton infiltrate each other, the Nie Xinhui team of Shihezi University in Xinjiang recently published a research paper published in the international famous botanical journal Acta Botanica, "genetic introgression analysis of agronomic traits improvement of Xinjiang upland cotton cultivars", pointing out the development direction and possibility for cotton breeding in the future.

The perfect integration of cotton quality and quantity has always been the direction of cotton genetic improvement efforts. The introduction of favorable alleles through interspecific hybridization to create introgression lines is an effective measure to improve the existing varieties. Tetraploid cotton domesticated by humans is divided into Gossypium hirsutum and island cotton. Upland cotton has high yield and wide adaptability, accounting for more than 95% of the total cotton output in the world. The quality of island cotton is excellent and its fiber is long and soft. With the expansion of cotton planting area in Xinjiang, researchers have bred many varieties of island cotton and upland cotton. However, the existence of introgression between sea and land varieties and their effects on fiber quality improvement have not been reported.

Through the high-throughput population sequencing technology of ten times of the cotton genome, the Nie Xinhui team established a high density genetic variation map of interspecific and intraspecific varieties of cotton and land cotton, and identified significant genetic introgression sites among the varieties of marine cotton.

The combination of gene introgression analysis and genetic analysis with gene and phenotypic association analysis and selection pressure has been studied. This is the first systematic and comprehensive analysis of the yield, quality and resistance molecular transmission mechanism of cotton varieties in Xinjiang over 40 years of artificial hybridization to create introgression materials, which provides a new theoretical basis for cotton molecular breeding in Xinjiang.

The Nie Xinhui team has been studying cotton molecular genetics and breeding since 2007, collecting and purifying all the conventional cotton varieties, early introduction and backbone parents from the first cotton varieties in Xinjiang in 1978, and the group resources covering the four cultivars and backbone parents from the introduction stage to the breeding stage of Xinjiang. After 2016-2018 years of 3 years, the phenotypic traits of population were obtained from 2 ecological areas with uniform cultivation and management conditions, namely, Korla in southern Xinjiang and Shihezi cotton research base in Northern Xinjiang.

The research was supported by the national key research and development projects and the National Natural Science Foundation of China. The Nie Xinhui team hopes that the research results will promote the development of cotton breeding in Xinjiang, expand and innovate the high-efficiency and precision breeding of Xinjiang cotton, contribute to the scientific research personnel of Xinjiang's cotton production, and truly achieve scientific research and promote the development of productive forces.