早稻苗期耐冷性的品种间差异及其评价

Varietal Difference and Evaluation on Seedling Cold Tolerance of Early Season Rice

为了筛选适宜于早稻机插秧栽培的苗期耐冷性品种,2012年以19个早稻品种为材料,采用3种人工低温(6.0、8.0、10.0℃)和常温(CK)处理,测定了与幼苗耐冷性相关的6项生理生化指标。结果表明:(1)在3种低温处理条件下,幼苗电导率、含水量、叶绿素含量、MDA含量、可溶性糖含量、POD活性均与常温条件下(CK)的差异显著,可作为苗期耐冷性鉴定的评价指标。(2)除了幼苗叶绿素含量外,其他5项指标的品种间变异系数均以10.0℃处理最大,是苗期耐冷性鉴定的最适宜低温处理。(3)根据所测定的上述5项生理生化指标,利用隶属函数法和聚类分析将19个早稻品种分为3个耐冷性等级:强耐冷性品种(株两优505等6个品种),中耐冷性品种(中优1号等8个品种),冷敏感性品种(株两优06等5个品种)。

To select cold tolerance rice varieties at seedling stage to be suitable for machine transplanting cultiva- tion in early season, pot experiment with 19 early rice varieties was conducted under differently artificial low tem- perature （6.0∽C ,8.0∽C and 10.0∽（2 ） and normal temperature condition. Six physiological and biochemical inde- xes related to the seedling cold tolerance were analyzed. Result showed that ： （ 1 ） under three low temperature con- dition,seedling electrolyte leakage, MDA content, soluble sugar content, chlorophyll content, water content and POD activity were significantly different from those under the normal temperature （CK） ,which could be suitable for the physiological indexes of seedling cold tolerance identification ; （ 2 ） besides seedling chlorophyll content, the variation coefficients of the other five physiology indexes among tested varieties were the largest under 10.0∽C temperature condition, which could be suitable for the low temperature indicator of cold tolerance identification ; （3） based on the above five physiological and biochemical indexes, 19 tested varieties were grouped into 3 levels of the cold tolerance by using the subordinate function and the cluster analysis：strong cold tolerance varieties （Zhuliang- youS05, Tyou167, Jinyou706, TyoulS, Tanliangyou921, Zhuliangyoul20 ）, intermediate cold tolerance varieties （ Zhongyoul hao, Jinyou268, Zhongyou463, Zhongzao35, Tanliangyou83, Baliangyoul8, Zhongzao39, Tyou987 ）, cold sensitive varieties （Zhuliangyou06,Xiangzaoxian42.Zhuliana∽coul12_Zhuli∽,∽,,,∽,,TNfi 7h,,1; ∽10∽