播期与地点对不同生态类型粳稻淀粉RVA谱特性的影响

Effects of sowing dates and sites on starch RVA profile characteristics of different ecological types of rice( Oryza sativa L. japonica)

为探讨不同地点和播期对稻米淀粉RVA谱特性的影响,以不同生态类型的5个粳稻品种为材料,在江苏省选择4个不同纬度地点,通过分7期播种试验研究稻米淀粉RVA谱特征值的差异。结果表明,8个特征值中除峰值时间在地点间差异未达到显著水平外,其他特征值在地点、播期和品种间的差异均达到显著或极显著水平,多数特征值以品种对其影响最大。不同生态条件间淀粉RVA谱特性差异明显,但随纬度的变化趋势不明显。其中,峰值黏度、热浆黏度和崩解值等特征值由大到小均依次为淮安点>苏州点>连云港点>扬州点。冷胶黏度和回复值呈现北高南低的趋势,连云港点和淮安点显著高于扬州点和苏州点。消减值随纬度的升高呈增加趋势,其中苏州点的消减值显著低于其他3个地点。糊化温度和峰值时间在不同纬度间变化较小。随播期的推迟,峰值黏度、热浆黏度、冷胶黏度和峰值时间4个特征值呈减小趋势,而消减值和回复值呈增加趋势,崩解值呈先升后降的趋势,糊化温度表现为先降后升的趋势。RVA谱特征值在不同地点随播期的变化趋势基本一致,均以早播为佳,同时RVA谱特征值在江苏省北部地区受播期的影响较大。8个RVA谱特征值以消减值的变异系数最大,峰值时间的变异系数最小。5个品种中以南粳46的峰值黏度和崩解值最高,而消减值和回复值最低,其RVA谱特性最优,蒸煮食味品质最好。连粳4号的峰值黏度和崩解值较高,消减值和回复值较低,其RVA谱特性也较好。说明不同播期和地点对不同生态类型粳稻淀粉RVA谱具有较大影响,不同地点间淀粉RVA谱特性差异明显,但随纬度的变化无明显趋势,不同播期间RVA谱特性的差异显著,同一品种在适宜种植区域内要获得较优的RVA谱特性应尽可能早播。

In order to elucidate the effect of differ-ent sites and sowing dates on RVA profile characteristics,the rice starch RVA profile characteristics in Jiangsu prov-ince were studied in four rice planting regions with five ja-ponica varieties as materials under seven sowing date treat-ments. The results showed the effects of site, sowing date and cultivars on RVA profile characteristics were significant ex-cept for peak time in different sites. The varieties had the greatest effect on most RVA profile characteristics. RVA profilecharacteristics showed obvious difference under different ecological conditions. The highest peak viscosity, hot paste viscos-ity and breakdown viscosity was seen in Huaian, followed by Suzhou, and the lowest was in Yangzhou. Cool paste viscosityand consistence viscosity performed higher in the north than in the south. Setback viscosity showed an increasing responseto latitude rising. Pasting temperature and peak time changed slightly with latitudes. Along with the delayed sowing date,peak viscosity, hot paste viscosity, cool paste viscosity and peak time decreased whereas setback viscosity and consistenceviscosity increased, and breakdown viscosity increased first and then decreased whereas pasting temperature decreased firstand then increased. The RVA profile characteristics were in favor of early sowing at various sites, and were affected by so-wing date in the north of Jiangsu province. The variation coefficient of setback viscosity was the largest while peak time wasthe smallest among eight RVA profile characteristics. RVA profile characteristics of Nanjing 46 were the best with the high-est peak viscosity and breakdown viscosity, and the lowest setback viscosity and consistence viscosity among five varieties.It is recommended that early sowing is beneficial for better starch RVA profile characteristics of the same rice variety.