Abstract: By setting up five seeding-time treatments at five different latitude zones in four Jiangsu rice growing regions(the latitude ranges from 31.3° N to 34.7° N), the RVA profile variation characteristic of the middle maturity two-line hybrid rice Liangyoupeijiu with good quality and high yield was studied. The RVA profile of Liangyoupeijiu was easily influenced by environmental factors. It was noted that at a latitude less than 32.4°, the variety possesed the best RVA profile, such as higher peak viscosity and lower setback value and pasting temperature. Moreover, from the seeding-time experiments, it was found that the RVA profile of Liangyoupeijiu worsened as the seeding was postponed, and the peaking viscosity would markedly increase and setback value would decrease with the increase of average temperature during the seeding period. Therefore, Liangyoupeijiu should be planted as early as possible for improving its grain quality.

Key words: rice, starch viscosity characteristics, latitude, seeding time, productive phase, average temperature

摘要： 在江苏4个稻作区的5个不同纬度点（纬度范围为31.3°N~34.7°N），设置了5个播期处理，研究了优质高产的两系杂交中籼稻两优培九的稻米RVA谱变化特征。 两优培九稻米RVA谱易受环境影响，该品种最佳的稻米RVA谱主要出现在纬度点32.4°N及以南地区，北移种植则导致RVA谱品质下降，即峰值黏度下降，消减值、糊化温度增加。RVA谱随播期的推迟呈变劣的趋势。结实期较高的平均温度可显著增加峰值黏度、降低消减值，因此两优培九以早播栽培为佳。

关键词: 稻米, 淀粉黏滞性, 纬度, 播种期, 结实期, 平均温度