水稻苗期氮素吸收利用效率的遗传分析

Genetic Analyses on Nitrogen-Absorbing Ability and Nitrogen-Utilizing Efficiency of Rice at the Seedling Stage

利用主基因-多基因混合遗传模型,对由韭菜青×IR26杂交和自交构建的一个由220个家系组成的重组自交系群体(F8)的苗期吸氮能力和氮素生理利用率进行了遗传分析。水稻苗期硝态氮吸收能力、铵态氮吸收能力和氮素生理利用率均由两对主基因+多基因模式控制。硝态氮吸收能力的主基因遗传率为63.20%,多基因遗传率为20.64%,两对主基因之间有加性和上位性效应;铵态氮吸收能力的主基因遗传率为55.67%,多基因遗传率为0.03%,两对主基因之间具有显性上位性效应;氮素生理利用率的主基因遗传率仅为19.47%,多基因遗传率达67.46%,两对基因之间具有重叠效应。对水稻氮高效利用品种的选育策略进行了讨论。

A RILs population consisting of 220 lines （Fs） derived from the cross between rice variety Jiucaiqing （japonica） and IR26 （indica） was evaluated to analyze inheritance of nitrogen-absorbing （NA） ability and physiological use efficiency （NUE） at the seedling stage by using the major gene plus polygene mixed inheritance model. The NO3^- absorbency, NH4^＋ absorbency and NUE of rice seedlings were genetically controlled by genetic mode of two major genes plus polygenes. The heritability values of major genes for NO3^- absorbency, NH4^＋ absorbency and NUE were 63.20%, 55.67% and 19.47%, respectively, and the values of polygene for the three traits were 20.64 %, 0.03 % and 67.46 %. There were additive and epistasis effects for the NO3^- absorbency, epistasis effect for the NH4^＋ absorbency and cumulative effect for the NUE respectively between each two major genes. The strategy to breed new rice variety with high absorbing ability and use efficiency of nitrogen was discussed.