| Several variant offspring with different seed colors such as white, black and purple, composed of mauve, carmine and coffee, were selected from introducing Chinese sorghum DNA into common wheat Jihe916 through pollen-tube pathway. In this study, nutrition quality of offspring and dynamic of pigment contents at different seed development stages were analyzed, Jihe916 used as white kernel CK and black wheat Hedong wumai526 as black kernel CK. At the same time, insertion of exogenous DNA was validated at molecular and protein levels, as well as in plant morphologic characters. The main results were as follows:1 The result of nutrition qualitative analysis indicated that the contents of protein, total amino acids, essential amino acids, healthy mineral elements and solute sugar in white, black, mauve kernel variant offspring were higher than in the receptor Jihe916. Therefore it could be concluded that they had special nutritious value and benefited to health. The utilization of variant offspring in the process of black foods was wide.2 The study on the dynamic research of pigment contents at different seed development stages showed that contents of chlorophyll, carotinoid in seeds of four different seed-color variant offspring all reduced gradually along with the increase of development days, the same as white kernel CK. It was also indicated that contents of chlorophyll and carotinoid in mauve, carmine and coffee kernel were related with the colors of seeds, e.g. the deeper colors, the less content. There was obvious difference of anthocyanidin change current between purple and black kernel. The former was a curve with only an apex but the latter was with two. But anthocyanidin was not detected in white kernel CK all the time. It was confirmed that the apex stage was the best time to utilize the anthocyanidin. And we deduced that the components of seed anthocyanidin of different color kernel were different.3 60 random primers were used for RAPD verification, and the steady specific bands could be amplified in the donor, receptor and three variant offspring by 11 of them. The polymorphism proved that the fragments of exogenous DNA were inserted into the genome of receptor. Because of the random insertion, the different variation of characteristics took place in various offspring.4 The results of POD and EST electrophoresis showed that there were only differences in the activity of isozymes between white, black, mauve kernel variant offspring' patterns and the receptor Jihe916 when leaves at the seedling of single-leaf were used as material. But there were lots of differences, which were appearance of new bands and disappearance of the receptor's when seeds at the milky stage as material. This proved that the genome structure of the receptor had changed due to the insertion of Chinese sorghum DNA fragments. So new enzymes had formed and apparent characteristics had variated at some corresponding stages of individual development.5 The result of seed gliadin electrophoresis showed that there were marked differences in the atlas between white, black, mauve kernel variant offspring' patterns and the receptor Jihe916, which were appearance of new bands and disappearance of the receptor's. It was also showed that the atlas of different offspring was not the same. Thus it was further verified that the insertion of exogenous DNA lead to the silence of intrinsic coding genes and the expression of new genes. This brought to variant offspring the components of gliadin different from the receptor.6 The main variations of offspring in the plant morphologic characters were special seed-color, tall plant height, fat leaves and thick stalk. It was more important that some special variation phenomena took place at the developmental stages of purple kernel variant offspring' plant. These variations proved that the DNA fragments of Chinese sorghum had inserted into the genome of receptor from another side, which lead to the expression of some donor's characters in variant offspring to some extent.7 Based on the... |
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