Distribution of grain hardness and puroindoline alleles in landraces, historical and current wheats in Shandong province

Abstract

Studies on the grain hardness and puroindolines alleles in wheat cultivars released in different historical periods, are helpful for breeding wheat cultivar with optimal endosperm texture. In the present study, 523 accessions from Shandong Province including 431 landraces, 63 historical cultivars and 29 current cultivars were used to evaluate the SKCS hardness and distribution of puroindoline alleles (Pins). Distribution of grain hardness differed in landraces, historical cultivars and current wheats, with 75.6%, 20.4%, and 3.9% of hard texture, and 20.4%, 19.0%, and 13.8% of mixed wheats, and 3.9%, 68.3%, and 58.6% of soft grains, respectively. Six genotypes of Pina and Pinb were present in landraces, in which Pina-D1a/Pinb-D1p and Pina-D1b/Pinb-D1b were the dominant genotypes, accounting for 38.0% and 59.6% of hard wheat, respectively. Compared with landraces, the polymorphism of Pina and Pinb was decreased in historical cultivars. Pina-D1b/Pinb-D1a, Pina-D1a/Pinb-D1b, and Pina-D1a/Pinb-D1p accounted for 37.5%, 37.5%, and 25.0% of hard wheat, respectively, whereas, Pina-D1a/Pinb-D1b was the only genotype presented in hard genotype of current cultivars surveyed. A novel Pinb allele with double mutations at the positions of 96th (C to A) and 265th (deletion of A) was found in three landraces, and was designated as Pinb-D1aa.