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In order to understand the genetic diversity of southwest China waxy corn resources, and waxy maize origin of evolutionary lines eventually reveal the accumulation of experimental data, provide useful clues. In this study comes from the Southwest China, Guizhou and Yunnan 9 waxy corn and normal corn compared the genetic differences between these two subspecies materials, from the level of morphology, biochemistry and molecular biology. 1. From the results of morphological studies, waxy and common corn growth period traits and plant traits there are large differences compared to normal corn, waxy corn whole growth period is longer, larger plant type , AIS longer; clustering analysis based on principal component values ??show that these two differences is to determine the waxy corn species and Jade Mia interspecific genetic distance of the main factors, despite the waxy corn also exist between the reproductive traits of genetic differentiation, but showed a waxy variation between corn is less than the trend of variability between waxy and common corn, waxy corn little difference in yield and corn; due to the larger artificial selection pressure. 2. In this study, 14 tested materials young leaves the Isoperoxidases research results show that: the POD Isozyme in waxy corn species, jade Mia species, waxy corn, corn sub there are differences within species, variability in the performance of the enzyme number of bands, the band mobility of the enzyme, the enzyme band tinctorial strength. Most waxy corn peroxidase enzyme spectrum with all 14 material having a fifth band, which is consistent with the results of previous studies, the fifth with corn type originated in China has a sign with a type. 3. 79 SSR primer pairs were detected in 330 alleles, allelic variants on the average per locus was 4.18, primers and variable sites can cover the entire genome of the Institute of synthesis primer polymorphism. the primer bnlg1292 can be used as specific SSR markers to distinguish between waxy and common corn. SSR markers genetic distance between the 14 tested materials found genetic differences between various materials, within the range of 0.535-0.695, with an average of 0.602, indicating that the genetic basis of different materials, which is wider various groups that exist within the cumulative genetic variation and genetic variation between groups. Cluster analysis based on a two-state data show that at the molecular level, waxy corn indeed exist with Normal Corn larger genetic differences, such differences not only in with the the wax gene and its related sites, but also throughout the entire genome: 4. Waxy corn maize genetic differences, can not say waxy maize originated by normal corn by single-gene mutations. The origin of the waxy corn pathway, the need for waxy corn with Italy Zhuo, wild relatives is a material of waxy corn and corn and waxy corn and cultivation jade Mia kinds of comparative genomics research, also need to use the plant system taxonomic research tools, chloroplast DNA rbcL gene sequence comparison and nuclear DNA ITS sequence analysis, bifurcation analysis and reconstruction corn is the origin of evolutionary relationships; 5. Genetic differences compared on the basis of this study, a brief discussion of the classification of cultivated corn, waxy corn and normal corn that is divided into two subspecies is reasonable. It was also found that individual due to the new type of hybrid introgression, and thus that geographic isolation, natural selection, artificial selection and introgression is the main reason for the evolution of the southwest of waxy corn and corn. Based on the above findings, waxy and common corn material that has a large genetic differences, genetic diversity is rich, with great theoretical research and breeding practical value.
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