Abstract:

【Objective】The purpose of the present research was to develop functional markers of protein phosphatase 2A structural subunit gene PP2Aa in common wheat (Triticum aestivum L.) for marker assisted selection in breeding of drought tolerance. 【Method】Based on the single nucleotide polymorphism (SNP) in the sequences of PP2Aa gene in common wheat and its wild relative species, three genome-specific primer pairs and six allele-specific primer pairs were designed. The Chinese Spring nulli-tetrasomic lines, a recombinant inbred line (RIL) population (Opata 85 × W7984) and a doubled haploid (DH) population (Hanxuan 10 hao× Lumai 14) were used for genetic location and mapping of TaPP2Aa. 【Result】The TaPP2Aa gene was located on chromosomes 5A, 5B and 5D. TaPP2Aa-B was mapped in the intervals between markers Xwg909 and Xgwm67 on chromosome 5B in RIL population, 4.0 cM and 3.6 cM from the flanking markers, and between markers Xgwm234 and WMC363 on chromosome 5B in DH population, 7.5 cM from WMC363, 3.6 cM and 11.4 cM from the common marker Xgwm67 in two populations, respectively. TaPP2Aa-D was mapped in the interval between markers Xcmwg770 and Xbarc205 on chromosome 5D in RIL population, 9.8 cM and 10.0 cM from them. 【Conclusion】The present study mapped the TaPP2Aa on the homoeologous chromosomes 5A, 5B and 5D.Through comparative analysis with main effect QTLs for stress resistance in DH and RIL genetic populations, the genetic linkage between TaPP2Aa and stress-resistant QTLs was identified. The functional markers developed for TaPP2Aa-B and TaPP2Aa-D can be used for marker assisted selection to enhance the efficiency of wheat stress-tolerant improvement.