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