Genetic variation and heritability of grain protein deviation in European wheat genotypes

Ellen F Mosleth,Malcolm J Hawkesford,Marie Lillehammer,Andrew B Riche,Abrar Hussain,Peter R Shewry,Till K Pellny,Simon Griffiths,Abigail J Wood

doi:10.1016/j.fcr.2020.107896

Abstract

There is a well-established negative relationship between the yield and the concentration of protein in the mature wheat grain. However, some wheat genotypes consistently deviate from this relationship, a phenomenon known as Grain Protein Deviation (GPD). Positive GPD is therefore of considerable interest in relation to reducing the requirement for nitrogen fertilization for producing wheat for breadmaking. We have carried out two sets of field experiments on multiple sites in South East England. The first set comprised 11 field trials of 6 cultivars grown over three years (2008-2011) and the second comprised 9 field trials of 40 genotypes grown over two years (2015-2017) and 5 field trials of 30 genotypes grown in a single year (2017-2018). All trials comprised three replicate randomized plots of each genotype and nutrient regime. These studies showed strong genetic variation in GPD, which also differed in stability between genotypes, with cultivars bred in the UK generally having higher GPD and higher stability than those bred in other European countries. The heritability of GPD was estimated as 0.44, based on data from the field trials of 30 and 40 genotypes. The largest component contributing to the genetic variance was genotype (0.30), with a smaller contribution of the interaction between genotype and year/site (0.11) and a small (but statistically significant) contribution of nitrogen level. These studies suggest that selection for GPD is a viable target for breeders.

Highlights

Wheat is the most important food grain in temperate countries, accounting for about 20–50% of the total intake of calories in humans
It has been estimated that globally only 33 % of the applied nitrogen fertilization is recovered in the harvested grain (Raun and Johnson, 1999), which has led to a focus on nitrogen use efficiency (NUE)
Some wheat genotypes consistently deviate from this relationship, a phenomenon known as Grain Protein Deviation (GPD) (Monaghan et al, 2001)

Summary

Introduction

Wheat is the most important food grain in temperate countries, accounting for about 20–50% of the total intake of calories in humans. It plays a crucial role in food security and increases in production are required to feed the growing global population. NUE is a product of the efficiency of N uptake (NUpE) multiplied by the utilisation efficiency (NUtE). The former is the entire above ground mass as a fraction of total

Methods

Results

Conclusion