The Study On Genotypic Difference And Segregation Trends In The Trait Of Starch Quality Of Potato

With potato starch processing industry expansion in China, it has become a main priority in potato breeding to develop the special purpose potato cultivar for starch processing industry. It would be beneficial for the potato grower, processor and breeder to classify potato resources for special use, to choose and prepare crossing parents for high starch breeding, and to identify and screen starch content and quality characteristics in the first generation clones or advanced generation clones. In this research, 56 potato cultivars and germplasm with favorable combined characteristics, 72 advanced generation clones and 111 first generation clones were evaluated for their five quality indexes, potato starch content, amylase content, gelatinization temperature, starch viscosity temperature and starch viscosity, by analyzing characteristic parameter, frequency distribution, correlation coefficient, cluster and cross comparison. The main results are as follows:1. Seven groups were generated by cluster analysis of potato cultivar and germplasm. The first and second groups with high starch content and starch viscosity included the Dongnong 00-33048, Shepody, FL1771, Atlantic, Kexing 12, Kexing 13 and Yan 97-8. The third and fourth groups with moderate starch content and starch viscosity involved 18 materials.2. Five groups were developed by clustering potato advanced generation clones. In the second group were 33033, 33182, 43213, 33441, 43209, 33089, 33202, 33424 and 33293, which had high starch content and starch viscosity. In the first, third and fourth groups were 44 materials of moderate starch content and starch viscosity.3. Six groups were produced by cluster method from the first generation clones. Sixteen clones were located in the second group, which were of high starch content and starch viscosity. Thirty four clones with moderate starch and starch viscosity were placed in the third and fourth group.4. Five crosses were compared by starch quality characteristic parameters and frequency distribution. High starch crosses were Dongnong303×Ke200029-26, Dongnong303×Yukon Gold and Dongnong303×H7. Crosses with lower amylose content included Dongnong 303×Kexin16, Dongnong303×Huangmazi, Dongnong303×Yukon Gold and Dongnong303×H7 The crosses with the lowest gelatinization temperature was Dongnong303×H7. Dongnong303×Kexin16, Dongnong 303×Huangmazi, Dongnong 303×Yukon Gold and Dongnong 303×H7 were the crosses of low starch viscosity temperature. Dongnong 303×Kexin 16, Dongnong 303×Huangmazi, Dongnong 303×Yukon Gold and Dongnong 303×H7 were considered as the crosses with higher starch viscosity.