Abstract:To understand the effects of nitrogen top-dressing amounts on starch gelatinization and retrogradation properties of spring and autumn sown waxy maize at the jointing stage, a study was carried out at the Experiment Farm of Yangzhou University in 2008. There were three cultivars (Suyunuo 5, Kennian 1 and Suyunuo 1) and three nitrogen top-dressing amounts (0, 150 and 300 kg/ha) in the study. The results show the main waxy maize starch gelatinization and retrogradation properties are significantly affected by the single factor and interactions between the nitrogen top-dressing amount at the jointing stage, sowing date and cultivar. In general, the gelatinization and retrogradation characteristics are better under the N 150 kg/ha nitrogen top-dressing amount and the autumn-sowing condition, especially for the cultivar Kennian 1, that is the raw starch has a lower peak temperature (Tp), higher enthalpy of gelatinization (ΔHgel) and low percentage of retrogradation (%R). Results of the correlation analysis indicate that the percentage of retrogradation is positively correlated with enthalpy of retrogradation (ΔHret) (r= 0.82, P< 0.01) and Tc (r= 0.47, P< 0.05), and ΔHgel is positively correlated with peak height index (PHI)(r= 0.53, P< 0.05) and is negatively correlated with Tp (r= -0.53, P< 0.05) and Tc of retrograded starch(r= -0.52, P< 0.05). ΔHret is positively correlated with though onset temperature (To) of retrograded starch (r= 0.46, P< 0.05) and PHI of retrograded starch (r= 0.66, P<0.01). Considering the starch gelatinization and retrogradation properties in different treatments, the autumn sowing waxy maize cultivars and the N 150 kg/ha nitrogen top-dressing amount at jointing stage are suitable to get better starch.
全 文 :PDF 文件使用 "pdfFactory Pro" 试用版本创建 www.fineprint.cn PDF 文件使用 "pdfFactory Pro" 试用版本创建 www.fineprint.cn PDF 文件使用 "pdfFactory Pro" 试用版本创建 www.fineprint.cn PDF 文件使用 "pdfFactory Pro" 试用版本创建 www.fineprint.cn PDF 文件使用 "pdfFactory Pro" 试用版本创建 www.fineprint.cn PDF 文件使用 "pdfFactory Pro" 试用版本创建 www.fineprint.cn PDF 文件使用 "pdfFactory Pro" 试用版本创建 www.fineprint.cn PDF 文件使用 "pdfFactory Pro" 试用版本创建 www.fineprint.cn PDF 文件使用 "pdfFactory Pro" 试用版本创建 www.fineprint.cn