水、旱稻RIL系抽穗期根系性状的相关及通径分析

以水稻越富与旱稻IRAT109杂交获得的120个粳-粳重组自交系为材料，旱田种植在自建的根管中，考察抽穗期的根数、根基粗等6个性状，同时计算根茎比（地下部分鲜重／地上部分鲜重）。计算各性状间及其与根茎比之间的相关系数并进一步进行根系性状和地上部分生物重的通径分析。结果表明：根数与根茎比无相关性，根基粗与根茎比之间达极显著正相关，相关系数为0．317；根长与根茎比达到显著相关，相关系数为0．227；根鲜重、根干重和根体积与根茎比亦达到显著正相关，相关系数分别为0．631，0．447和0．488。对高根茎比和低根茎比株系根系进行比较，除根数外，其他性状的均值均为根茎比大的株系大于根茎比小的株系，说明根茎比可以作为作物根系抗旱性的一个指标；根鲜重、根干重和根长对地上部分生物重贡献较大。

Correlation and Path Analysis of Root Traits Using RIL Populations Derived from Japonica Lowland and Upland Rice Cross in Heading Stage

A Recombinant Inbred Line(RIL) population including 120 lines derived from the cross between Japonica upland rice IRAT109 and paddy rice Yuefu was used in this study.The data of RIL population and the parents were obtained under PVP pipe cultivated conditions in 2004.The data of root traits including root number,basal root thickness,maximum root length,root fresh weigh,root dry weight and root volume were obtained during heading stage in 2004,and the weight of shoot also was obtained to calculate the R/S(Ratio of Root to Shoot).Using R/S as the criteria of drought resistance,correlation analysis between root traits and R/S were conducted.The results showed that basal root thickness,root fresh weight, root dry weight and root volume had significantly positive correlation with R/S,while root number had no correlation with R/S;High R/S lines had thicker basal root,longer maximum root length and less root number,more root fresh weight and root dry weight than low R/S lines;and path analysis showed that root fresh weight,root dry weight and maximum root length made obvious contribution to shoot dry weight.