ABSTRACT
Milling and breadbaking quality of hard-textured wheat may be influenced by alternative alleles at the Wx loci controlling percent amylose in the endosperm, and the puroindoline (pin) loci controlling grain hardness. For this experiment, we developed recombinant inbred lines (RIL) from a cross between Choteau spring wheat cultivar and experimental line MTHW9904. Choteau has the PinB-D1b mutation conferring grain hardness and the Wx-B1a allele at the Wx-B1 locus conferring wild-type amylose content. MTHW9904 has the PinA-D1b allele conferring grain hardness and the Wx-B1b allele conferring lower amylose content, causing a partial waxy phenotype. RIL with the PinB-D1b mutation (n = 49) had significantly softer kernels, higher break flour yield, and higher loaf volume than lines with the PinA-D1b mutation (n = 38). Lines with partial waxy phenotype due to Wx-B1b (n = 43) had significantly lower kernel weight, lower amylose content, and higher flour swelling power than lines with wild-type starch due to Wx-B1a (n = 51). These results provide additional evidence for the positive effect of PinB-D1b on bread quality in hard wheats, while genotype at Wx-B1 was generally neutral for bread quality in this population. Interactions between the Pin and Wx loci were minimal.
