Comparison of five puroindoline alleles on grain hardness and flour properties using near isogenic wheat lines

Grain texture is one of the most important characteristics that affect the end-use quality of wheat (Triticum aestivum L.). Mutations in the puroindoline-a and puroindoline-b genes are associated with hard grain texture. The expression patterns of the PINA and PINB proteins differ among Pin alleles. We studied the effect of Pin alleles on grain hardness, and milling flour properties using near isogenic lines grown at two different locations. The genotype was found to significantly affect quality parameters related to grain hardness. Grain hardness, flour particle size, damaged starch content were significantly low in Pinb-D1b as compared to Pinb-D1c, Pinb-D1p, Pina-D1b, and Pina-D1k. Grain hardness of Pina-D1k, lacking both PINA and PINB, were the highest, followed by Pina-D1b lacking PINA. Pina-D1k and Pina-D1b showed high damaged starch contents and CO2 production. Damaged starch is associated with water absorption of flour and CO2 production during dough fermentation, an important characteristic in bread-making. The alleles might be useful for improving bread-making quality. These results indicate that the grain texture of hard wheat is affected by the amount of PINs each allele.