种植方式对陆稻中旱3号和水稻武香粳99-8米质的影响

在大田试验条件下，以陆稻中旱3号和水稻武香粳99-8为材，设覆膜旱种和裸地旱种2种方式，以水层湿润灌溉为对照，研究了种植方式对米质的影响。结果表明，与水种(对照)相比，中旱3号覆膜旱种的产量显著降低，而武香粳99-8覆膜旱种的产量则无显著差异，裸地旱种的产量均较对照显著降低。旱种可降低垩白度、粒长/粒宽、直链淀粉含量、胶稠度、峰值黏度，提高蛋白质含量和糊化温度；中旱3号覆膜旱种和裸地旱种以及武香粳99-8裸地旱种的垩白粒率显著低于对照，而武香粳99-8覆膜旱种则无显著差异。三种种植方式中，两品种均以覆膜旱种的垩白度、直链淀粉含量、胶稠度、崩解值和灌浆期稻株含N率下降值最小，蛋白质含量和消减值最大，籽粒Q酶活性维持在较高的水平。与武香粳99-8相比，中旱3号的垩白粒率和胶稠度显著降低，垩白度没有显著差异，粒长/粒宽、直链淀粉含量、蛋白质含量、崩解值和糊化温度显著提高。Q酶活性、籽粒灌浆参数与米质指标关系密切。旱种有利于改善稻米的外观和营养品质，但蒸煮食味品质有所变劣。

Effects of Cultivation Methods on Grain Quality in Upland Rice cv. Zhonghan 3 and Paddy Rice cv. Wuxiangjing 99-8

Upland rice and dry-cultivated paddy rice have been attracted more and more attention because of limited water resources in China,however,there is little information available on effect of cultivation methods on grain quality of upland rice and paddy rice.The objective of this study was to evaluate the difference between upland rice cultivar Zhonghan 3(japonica) and paddy rice cultivar Wuxiangjing 99-8(japonica) under three cultivation methods of moist cultivation(MC,control),plastic film mulching cultivation(PFMC) and bare cultivation(BC).The results showed that,compared with the MC,the grain yield was significantly lower under PFMC for upland rice,but no significant difference between PFMC and MC for paddy rice,and significantly reduced under BC for both upland and paddy rice.The chalkiness,the ratio of kernel length to kernel width,amylose content,gel consistency,and peak viscosity were lower,whereas protein content and pasting temperature were higher for PFMC and BC rice compared with those of MC rice.The percentage of chalky grains was significantly decreased under PFMC and BC for upland rice and under BC for paddy rice,but no significant difference between PFMC and MC for paddy rice.Chalkiness,amylose content,gel consistency,breakdown viscosity,and the declining amount of nitrogen content in plants from heading to maturing stages were the least,and protein content and setback viscosity were the most,and Q-enzyme average activity remained the highest level for PFMC among the three cultivation methods.Compared with paddy rice,upland rice showed lower percentage of chalky grains and gel consistency,no difference in chalkiness,and higher levels in ratio of kernel length to kernel width,amylose content,protein content and pasting temperature.The relationship between Q-enzyme activity and grain quality was similar to that between the grain-filling parameters from Richards equation.The results suggest that the dry cultivation can improve appearance quality and nutrient quality,whereas has negative effects on cooking quality.