水稻孕穗期抗冷鉴定指标选择

Identification index for cold resistance at the booting stage in rice

利用贵州地方抗冷品种与恢复系蜀恢527杂交所得的F2代20个单株为材料,在孕穗期经过人工气候箱17℃,5d处理后,测定植株的叶绿素、脯氨酸、电导率、包颈和结实率5个与抗寒有关的形态和生理指标,并进行主成分分析和通径分析。从相关系数矩阵可以看出,所有单项指标间都存在或大或小的相关性,使其信息发生重叠;主成分分析显示,按累计贡献率≥85%的标准,筛选出结实率因子(λ1=2.712)、电导率因子(λ2=0.86)和叶绿素因子(λ3=0.713)3个主成分,其对变异的累计贡献率达85.72%,可以概括绝大部分信息量。4个指标的通径系数从大到小的顺序依次为脯氨酸(0.26663)、叶绿素(0.22606)、包颈长度(-0.11041)和电导率(-0.33995),结实率的修正值可以有效地减少试验误差,增加结果的真实性和可靠性,同时也可以作为抗冷鉴定的指标。

Individual plants of 20 F2 crossed from Guizhou local cold-tolerant rice varieties and restorer line Shuhui 527. during the booting stage were treated at 17℃ for five days in the artificial climatic chamber to test chlorophyll, praline, electrical conductivity, panicle enclosure and seed setting rate, the five indexes correlated with cold resist- ance. Through principal component and path analysis. The correlation matrix indicated significant or specially significant correlation among all indexes. The results of principal component analysis showed that seed setting rate factor （λ1 = 2. 712）, conductivity factor （λ2 = 0. 86 ） and chlorophyll factor （λ3 = 0. 713 ）were selected, according to cumulative contribution standard t〉85%. These three principal components accounted for 85. 72% of total variations. Path coefficients of 4 indexes ranked as proline （ 0. 266 63 ）, chlorophyll （ 0. 226 06）, length of Panicle enclosure （ - 0. 110 41 ）, and conductivity （ -0. 339 95）. Correctional of seed setting rate may efficiently decrease experimental error, increase authenticity and veracity of results, and can be the indexs of cold resistance.