Genetic Diversity Of Colored-Grain Wheat And Genetic Analysis Of Pigment Content

The colored-grain wheat contains a great quantity of natural pigment. The differenceswere existed among the different color or varieties grain wheat. In this experiment, we used18varieties （lines） colored-grain wheat to reveal the relationship and genetic diversity. Andwe used six generations from the cross of Jihe916（ordinary color grain wheat） and D4hong（red grain wheat） for material to investigate the genetic model about the pigment content ofred grain wheat. The main results were as follows:1The aim of this experiment is to provide a kind of nondestructive measuring to test thecolor pigment content in colored-grain wheat. We may measure grey value of colored-grainwheat directly, and then calculated the pigment content through the mathematical model. Thegray value of colored-grain wheat was measured through the scanning images. And then thecolor pigment content of grain wheat was measured in each single kernel. The significantnegative correlation was existed between gray value and pigment contents. The correlationcoefficient is-0.540. Thereby the mathematical model between the purple-grain wheat greyvalue and pigment content which is Eg=0.2072-0.0015Xg was established.2Six generations of P₁P₂F₁BC₁BC₂and F₂from the cross of Jihe916（ordinary colorgrain wheat） and D4hong （red grain wheat） were obtained to analyze the genetic effects of thecolor pigment content by major gene-polygene mixed inheritance model. Results indicatedthat the heredity model of the color pigment content could be explained by mixed two majorgenes plus polygenes inheritance model（E model）. The two gene additive allelic effect valuewere-0.023. For the first gene of dominant effect （ha） and dominant degrees （ha/da）-0.012and0.514respectively, and the second genes of dominant effect （hb） and dominant degrees（hb/db） points to0.045and-1.97. The major genetic rate of the color pigment content inBC₁,BC2and F₂generations is59.26%,96.52%and96.52%respectively. The highest value isin F2and BC₂. Whereas, genetic rate of polygenes in BC1is the lowest.3To reveal the relationship and genetic diversity of colored-grain wheat, we analyzed18varieties （lines） with red, purple, blue, and black seed coats using305polymorphic SSRmarkers. A total of1084alleles were detected with3.6alleles per locus. The allele numbers inseven homoeologous groups （HG） were aligned as HG3>HG2>HG1>HG4>HG5>HG7>HG6 in red and purple wheat and HG3>HG2>HG1and HG4>HG5>HG7>HG6in black and bluewheat. The polymorphic information content （PIC） values in the seven homoeologous groupswere similar, which were0.525-0.543in red and purple wheat and0.517-0.545in black andblue wheat. Among the18colored-grain varieties （lines）, genetic difference was significant （P=0.0001）, and the genetic similarity coefficients ranged from0.41to0.76. According toUPGMA analysis, the18varieties （lines） were classified into six groups, which were inrelation to variety kindred and geographic distance.