Effect Of High Oil Corn Pollinator On Kernel Quality Of Common Corn And Their Physiological And Biochemical Basis

High oil corn (HOC) is a value-added cultivar's type corn, which contains more oil and higher quality protein than normal corn (NC). HOC has not been widely planted because its grain yield is lower than NC, thus its fine properties is hard to utilize. The technique of producing high oil grain with normal hybrid settles this problem successfully: it uses pollen of HOC to pollinate to NC, thus improves quality of kernel and guarantees equivalent yield of grain. In this research we compared the kernel's quality of NC pollinated with HOC's pollen with that of self-fertilized corn. The main results are as follows.1 The embryo weight, weight ratio and volume ratio of embryo to kernel and the content of kernel oil were significantly higher in NC pollinated with HOC's pollen than that of self-fertilized corn. The average oil content of all cross-fertilized kernel was about 35.41% higher than that of self-fertilized kernel. In the 9 crosses (which were 3 NC pollinated by 3 HOC), there were 5 treatments whose yield was higher than that of the maternal parent, with the ranges of 0.34% to 10.70%, but it was not significant. The results confirmed that the effect of xenia did not appear to increase or decrease the yield of seed parent, but did improved the grain quality.2 The xenia of high oil corn pollen significantly effected the component of fatty acids of NC kernel. Compared with self-fertilized of NC, the content of oleic acid increased significantly, whereas the content of stearic acid, palmitic acid and linoenic acid declined. The content of total unsaturated acid of all cross-fertilized kernel was higher than that of self-fertilized kernel of NC. In different periods of the maturing process of corn seeds, there was a similar trend of change in the content of fatty acids between different treatments. During the maturing process of corn kernel, the content of saturated acid and linolenic acid declined while the content of oleic acid and total unsaturated acid increased. In the course of the shaping of corn kernel, there was a positive relationship between the contents of palmitic acid and stearic acid, palmitic acid and linoleic acid, stearic acid and linolenic acid, and there was a negative relationship between the contents of palmitic acid and oleic acid, stearic acid and oleic acid, oleic acid and linolenic acid, oleic acid and linoleic acid. And the degree of correlation between the contents of palmitic acid and linolenic acid, palmitic acid and oleic acid, oleic acid and linolenic acid reached a highly significant level. The correlation between other fatty acids of different treatments disaccorded.3 The content of protein was higher in NC pollinated with HOC's pollen than that of self-fertilized kernel. The xenia effect of HOC did improve the NR activity in the ear leaves and GDH activity in NC kernel, and has an influence on the activities of GS and GOGAT to some degree, thus resulted in the difference of the competence of protein synthesizing between NC pollinated with HOC's pollen and the corresponding NC self-fertilized.4 Compared with self-fertilized of NC, the activity of SOD in grain of NC pollinated with HOC's pollen decreased, and the activity of CAT increased. The content of MDA in cross-fertilized kernel of HOC and NC was lower than that of self-fertilized kernel of NC while the soluble protein content increased. The results showed that the xenia effect of HOC influenced the activity of protective enzyme in kernel, reduced the damage to cell membrane lipid to some degree while enhanced the competence of metabolizability.5 The difference between NC pollinated with HOC's pollen and self-fertilized of NC was analyzed basing on their soluble protein and isozyme profiles obtained through vertical slab polyacrylamide gel electrophoresis (PAGE)in order to explore the physiological mechanism of differentiation between the treatments at protein or isozyme level. A significant diversity of cross-fertilized seed and their parents was found in terms of spectrum change of soluble protein and esterase isozymes among those strains, and the obvious difference in the number of bands and activity of bands with the same Rf value was also detected. There were new bands in cross-fertilized seed except all bands included in their parents. The results reflected that there was profound change in genetic and physiological characteristics of NC pollinated with HOC's pollen.