Photoperiod 1 (Ppd-H1) affects leaf size and phyllochron in barley

Abstract -  Barley (Hordeum vulgare) ranks fourth among the world's cereal crops and thanks to its wide range of genetic diversity it is often grown in areas that are less favourable to the cultivation of other cereals. The exploitation of germplasm collections and genetic stocks, coupled with high-throughput genotyping platforms has enhanced our ability to identify the genetic determinants of complex traits of agricultural importance. Through a genome wide association scan (GWAS) in a diverse panel of 138 European winter barley cultivars grown in the field and genotyped with the Illumina iSelect 9k SNP chip, we were able to identify the photoperiod-responsive gene Ppd-H1 as a candidate for the major QTL for leaf size. Phenotyping of three independent introgression lines (ILs) confirmed that natural variation at Ppd-H1 affects barley leaf size by influencing the rate of age-dependent progression of leaf development. The coordination of leaf growth with flowering may be part of a reproductive strategy to optimize resource allocation to the developing inflorescences and seeds.

 Host: Lenka Havlickova