The Quality Of Jiangsu Early Maturing Late Japonica Rice Varieties And Its Nitrogen Regulatory Effect

The test carried out in2011-2012in the experimental farm of Yangzhou University, following wheat stubble.23early maturing late japonica rice which suitable for planting in Jiangsu Province were used as the tested materials, to study the response of rice quality especially the nutritional quality to seven nitrogen levels(0,10,12.5,15,17.5,20,22.5kg/667m2). The main findings are as follows:(1) Nitrogen levels significantly affect the quality of the tested varieties of rice processing, and there is a big difference between cultivars. The brown rice rate, milled rice rate, head rice rate were increasing as the nitrogen levels increased, head rice rate is the most obvious response to nitrogen levels, and the large differences between varieties.(2) There were significant differences of rice appearance between cultivars and nitrogen levels. The chalkiness rate significantly reduced with increasing nitrogen levels, the chalkiness size and the chalkiness degree were significantly increased with increasing nitrogen levels. The effect of varieties on rice appearance quality was significantly greater than the role of nitrogen levels, which makes the chalkiness degree among varieties biggest difference.(3) There were significant differences between gel consistency and amylose of the test material with increasing nitrogen levels, gel consistency gradually shorter while amylose content decreased, the difference between nitrogen treatments was significant. Pasting temperature less affected by nitrogen levels, there was no significant difference between the different nitrogen levels. Peak viscosity, hot viscosity, breakdown, final viscosity, setback as rice cooking and eating quality indicators, there is a difference between nitrogen levels, and various factors have reduced with increasing nitrogen levels except the setback, the impact of nitrogen levels on the setback was significantly greater than the other indicators. (4) There were differences in the test early maturing late japonica rice protein and its four components content in the nitrogen level, albumin, globulin, gliadin, gluten and total protein content was increasing with increasing nitrogen levels, but the variation of each index were different from each other between the nitrogen levels. The average content of protein and four components were8.15%,0.54%,0.68%,0.72%,6.21%. In the four components of the protein, the highest one is gluten content, the lowest is albumin content, and a considerable proportion of globulin and gliadin. In certain nitrogen level, albumin and globulin content increased with increasing nitrogen levels, but did not change significantly if over a certain range. Gliadin, gluten and protein content showed a significant increase in the trend of increasing nitrogen levels.(5) There were differences in the response of the nitrogen levels in different types of amino acids, and the different types of amino acids are also different between different species. A variety of amino acid content are all increased with increasing nitrogen levels. Serine, glutamic acid, alanine, valine, tyrosine, phenylalanine, histidine and arginine, etc.8kinds of amino acids content are significantly or extremely significant increase with the increase of nitrogen levels. Isoleucine showed that N treatment was significantly higher than the treatment without any nitrogen, while the amount of nitrogen fertilizer on their content is not significant. Aspartic acid, threonine, glycine, proline, leucine, methionine, lysine and other amino acids in the individual processing the difference was not significant, other treatment difference was significant. The determination of total16kinds of amino acids is higher in the selected representative varieties Thai japonica394.(6) Nitrogen levels has a significant effect on Cu, Fe, Mn, Zn, Ca, Mg content of rice. The content of each element have shown a decreasing trend after the first increase with increasing nitrogen levels. The average content of Cu, Fe, Mn, Zn, Ca, Mg in the nitrogen level is2.71mg/kg,9.22mg/kg,7.13mg/kg,10.64mg/kg,82.59mg/kg,218.49mg/kg.12.5N level is the most favorable for the accumulation of Cu and Fe in rice, Mn, Zn, Ca, Mg four elements get higher accumulation under10N.