小麦磷素利用效率的基因位点及其交互作用

利用小麦W7984和Opata85作亲本 ,通过一粒传而获得F7重组近交系 (RIL)群体。对该群体的 114个株系分别在正常供磷和低磷胁迫下探讨小麦地上部磷素利用效率 (SPUE)和全株磷素利用效率 (WPUE) ;并根据该群体而构建的遗传图谱包括覆盖整个染色体组的 918个RFLP标记 ,研究 2种供磷情况下小麦磷素利用效率的基因位点及基因间互作。结果表明 ,正常供磷 ,有 2个与SPUE有关的QTL ,分别位于染色体 1B和 5A上 ,变异解释率分别为 6.55 %和 1 1.61 % ;与WPUE有关的QTL有位于染色体 2B、5A和 7A上的 3个 ;SPUE和WPUE还分别受一对互作位点的影响。在磷胁迫下 ,有 3个QTL与SPUE有关 ,分别位于染色体 2D、3B和6D上 ,变异解释率分别为 14.2 %、7.73%和 6.58% ;与WPUE相关的 2个QTL分别位于染色体 2D、7A上 ,变异解释率分别为 18.01 %和 10.73 % ;SPUE受上位效应的影响。 7A染色体对于小麦的磷素利用效率有着重要的作用 ,位于该染色体上的片段Xfba354 Xfba69在 2种供磷情况下都显著影响WPUE ,同时此片段在正常供磷下还与其它基因互作而影响WPUE。此外 ,5A染色体在正常供磷、2D染色体在低磷胁迫下分别对磷素利用效率 (PUE)有较强的作用。

Identification and interaction analysis of QTL for phosphorus use efficiency in wheat

An F 7 recombinant inbred line (RIL) population consisting 114 lines, derived from 2 varieties, W7984 and Opata85, were used in a hydroponic experiment with phosphorus (P) sufficient(0 25mmol/L) and deficient(0 025mmol/L) treatments After culture for 4 weeks, P concentration was measured in shoot and in root separately P use efficiency (PUE) for shoot (SPUE), or whole plant (WPUE) was defined as shoot or whole plant biomass production per mg of absorbed P by the whole plant 918 RFLP markers mapped on all genome were used for analysis of QTL for these parameters The results showed that, under P sufficient conditions, 2 QTL were identified for SPUE on chromosome 1B and 5A, respectively; 3 QTL were detected on chromosome 2B, 5A and 7A, respectively, influencing WPUE Under P deficient conditions, 3 QTL on chromosome 2D, 3B, and 6D were detected for SPUE, and 2 QTL on chromosome 2D and 7A for WPUE Epistatic interaction analysis indicated that there were 1 digenic interactions influencing SPUE and WPUE under P sufficient environment, only 1 digenic interaction was found controlling WPUE at P deficient level Among of the QTL detected, the locus on chromosome 7A influenced WPUE at both of the two P levels, and this interval also involved in the epistasis influencing WPUE under P sufficient environment, the genomic region containing this locus should be important for PUE in wheat Additionally, the results indicated that chromosome 5A was important for PUE under P sufficient environment, while chromosome 2D was important at P deficient level This research may be helpful to understand the genetic background in wheat for phosphorus utilization