GENETIC-ANALYSIS OF FERTILITY RESTORATION IN WHEAT USING RESTRICTION-FRAGMENT-LENGTH-POLYMORPHISMS

Fertility restoration for Triticum timopheevi Zhuk. cytoplasmic male sterility in wheat (Triticum aestivum L.) is controlled by both major fertility restorer (Rf) genes and modifier genes together with environment effects. Therefore, the breeding of efficient and stable male-fertility restorer lines (R-lines) should be facilitated by marker-assisted selection. This study was conducted to identify restriction fragment length polymorphism (RFLP) markers for the Rf genes, Rf1 and Rf4 in restorer line R113, and Rf3 and a Rf gene on 5D in cultivar Primepi. Polymorphic markers were mapped in testcross F-1 populations and their association with fertility restoration was analyzed by analysis of variance. Tbe results indicated that Rf4 was linked to Xksug48 located on 6BS in R113, Rf3 was linked to Xbcd249 and Xcdo442 on IBS, and Xcdo786 may be associated with the 5D Rf gene in Primepi. In addition, in R113 two other chromosome regions with fertility restoration-associated loci were detected by CD0786 and H1 on 5AL and CDO1189 on 7BS. A locus on 5DS, detected by BCD1871, showed significant epistatic effect on the expression of Rf genes. In Primepi, a locus on 5AL, detected by Xbcd183 and Xbcd876, had effects similar to Xcdo786. Two loci in 'Qu Xian Early A', identified by Xbcd871 and Xwg1026, may be associated with genes controlling ease of restoration in this male-sterile line (A-line). Except for Xbcd1871 and Xwg1026, the effects of other significant RFLP loci were additive in both populations.