Effect On Yield And Quality In High Starch Corn (DK1)and High Oil Corn(HO907) Under Different Nitrogen Rates And Densities

DK1 is a high starch corn specie from Monsanto, which starch content is 75.06% .The high oil corn is a new type corn specie that contain higher oil in grain, high additional worth corn in quality. Because both are high-quality corn species that, their cultivation technique hasn't modeled, causing its low yield and hardly expanded in production, and affecting its high-quality characteristic developed. In order to find the best cultivation mode that sieving both DK1 and HO907, this study adopt 4 N rates and 3 density rates to compare and study their effect on yield and quality. Then study the effect of different N rate on yield, quality and carbon and nitrogen metabolism of DK1.Main result as follows: 1 The best cultivation mode of DK1 and HO907 sieving 1.1The best cultivation mode sieving of high starch corn DK1 1.1.1The yield of DK1 The grain yield of DK1 increased significantly with N rate increasing. The grain yield in high nitrogen 300kg·ha^-1 was the highest. In density handle, the grain yield in D2 was the highest and was higher than other handles significantly. 1.1.2 The quality character of DK1 The starch and protein content of DK1 increased with N rate increasing. The average content in high nitrogen 300kg·ha^-1 was the highest. But the starch and protein content decreased with the density rate increasing. The starch and protein content in D1 was the highest. But the difference of the protein between D2 and D1 was not significant. The fat content in grain of DK1 decreased with N rate increasing. The fat content in N4 handles was lowest. In density handles, the fat content of D2 was lowest, and the difference between handles was significant. 1.2 The best cultivation mode of high oil corn 907 sieving 1.2.1 The yield of HO907 The yield of HO907 increased with N rate increasing. The yield in 300kg·ha-1 was highest. With the increasing of the density, the yield increased. In density handles, the yield in D3 was highest. 1.2.2 The quality character of HO907 The oil content and fat content in grain of HO907 increased with N rate increasing. Both of them in D1 were the highest. With the increasing of the density, both of them decreased. The content in D1 was the highest. But the difference of protein content between D2 and D1 was not significant. The starch content in grain of HO907 decreased with N rate increasing. The starch content in 300kg·ha-1 was lowest. In density handles, the starch content in D2 was lowest, and was lower than other handles significantly. Considering yield character and quality character, DK1 in 300kg·ha-1and 57000 plants·ha-1was best, HO907 in 300kg·ha-1 and 52500 plants·ha-1 was best. 2 Physiological basis of yield and quality in DK1 under different N rates With the N rate increasing, accumulation of dry matter and grain yield increased immediately; and the difference between different N rates was significant. LAI also increased immediately. With the N rate increasing, starch content and protein content of grain in DK1 increased immediately; but fattiness content decreased significantly. With the N rate increasing, the dissoluble sugar content of the DK1 decreased, decreased in the progress of growth, too. The amino acids content increased, but decreased in the progress of growth. With the N rate increasing, the chlorophyll content, Pn and Fluorescence parameters of ear leaf in DK1 increased immediately. The NR activity and dissoluble protein content increased immediately. But decreased in the progress of growth. SOD and CAT activity of ear leaf increased immediately With the N rate increasing, but decreased in the progress of growth. POD activity of ear leaf increased with N increased, which increased but decreased later in the progress of growth. The MDA...