不同播期早籼稻米质性状的变异及温度的影响效应分析

为揭示结实期温度对早灿稻米品质的影响，通过对全年8次分期播种的5个早灿稻品种的米质测定，结合结实期温度指标的相关性分析。结果表明：品种及米质性状对温度的反应有别，垩白和整精率的变幅最大，为温度反应敏感型性状；粒长和粒形及出糙率、精米率的变幅最小，为温度反应迟钝型性状；其它为温度反应中间型性状。因垩白基数的大小不同，导致米质优的品种播期间的变异系数大，米质劣的品种的变异系数小。结实期温度效应的诸因素协同影响米质，分3部分：含日均温、日均温差、日均最高、最低温的均温因子；含积温、天数、累计最高、最低温、累计温差的积温因子；全生育期天数作为影响最小的指标，对米质有一定影响。均温和积温因子对米质影响的方向和大小依品种而略有变化，两因子所含的各指标的影响力和影响效应一致。

Variation of Early Indica Rice Quality Traits in Eight Sowing-dates and Influence of Temperature on It

Variations or traits under different temperature are different. Chalkiness and ratio of head rice possessed the largest C.V ., be named sensitive trait for temperature. Length of grain, shape of rice, ratio of brown rice and milled rice rate possessed the minor C.V. , be named slow witted trait for temperature. Other traits were named middle trait. Superior rice variety possessed desirable C.V. because of little chalkiness. On the other hand, inferior rice variety possessed minor C.V. because of big chalkiness. All of the factors of temperature during ripening period taken great roles for rice quality, were divided into 3 parts. The first part includes daily average temperature, daily average highest temperature, daily average lowest temperature and daily average temperature variation, be called average temperature factor. The second part include days of ripening period, accumulate daily average temperature, accumulate daily highest temperature, accumulate daily lowest temperature and accumulate daily average temperature variation, be called accumulate temperature factor. The last is days of whole life, it takes the minor role. The influence of average temperature factor and accumulate temperature factor have a little change in view of different varieties. All of the traits in each factor have the same influence direction.