Assessing adaptive requirements and breeding potential of spelt under Mediterranean environment

Arie Y Curzon,Roi Ben-David,Ram Reifen,Asaf Avneri,Chandrasekhar Kottakota,Shimrit Bar-El,David J Bonfil,Kamal Nashef,Shahal Abbo,On Rabinovich

doi:10.1038/s41598-021-86276-1

Abstract

The rising demand for spelt wheat (Triticum aestivum ssp. spelta) as a high-value grain crop has raised interest in its introduction into non-traditional spelt growing areas. This study aimed to assess adaptive constrains of spelt under short Mediterranean season. At first screening of a wide spelt collection for phenology and allelic distribution at the photoperiod (PPD) and vernalization (VRN) loci was done. In addition an in-depth phenotypic evaluation of a selected panel (n = 20) was performed, including agronomically important traits and concentration of grain mineral (GMC) and grain protein (GPC) content. Results from both wide screening and in-depth in panel (group of 18 spelt lines and two bread wheat lines) evaluation shows that the major adaptive constraint for spelt under Mediterranean conditions is late heading, caused by day length sensitivity, as evident from phenology and allelic profile (PPD and VRN). All lines carrying the photoperiod-sensitive allele (PPD-D1b) were late flowering (> 120DH). Based on the panel field evaluations those consequently suffer from low grain yield and poor agronomic performances. As for minerals, GMC for all but Zn, significantly correlated with GPC. In general, GMC negatively correlated with yield which complicated the assessment of GMC per-se and challenge the claim for higher mineral content in spelt grains. The exceptions were, Fe and Zn, which did not correlate with yield. Spelt lines showing high Fe and Zn concentration in a high-yield background illustrate their potential for spelt wheat breeding. Improving spelt adaptation to Mediterranean environments could be mediated by introducing the insensitive-PPD-D1a allele to spelt wheat background. Following this breeding path spelt could better compete with bread wheat under short season with limited and fluctuating rain fall.

Highlights

The rising demand for spelt wheat (Triticum aestivum ssp. spelta) as a high-value grain crop has raised interest in its introduction into non-traditional spelt growing areas
Allelic profiles at the VRN1 and PPD1 genes of the germplasm lines showed that most genotyped spelt lines were spring types (Supplementary Table S2) but were photoperiod-sensitive (PPD-D1b), explaining the late heading of these lines in comparison to Israeli wheat checks (Supplementary Table S2)
PI 520066, TAS03, 109, carried a day length-insensitive (PPD-D1a) allele among those were the earliest spelt lines grown in this study

Summary

Introduction

The rising demand for spelt wheat (Triticum aestivum ssp. spelta) as a high-value grain crop has raised interest in its introduction into non-traditional spelt growing areas. In addition an in-depth phenotypic evaluation of a selected panel (n = 20) was performed, including agronomically important traits and concentration of grain mineral (GMC) and grain protein (GPC) content Results from both wide screening and in-depth in panel (group of 18 spelt lines and two bread wheat lines) evaluation shows that the major adaptive constraint for spelt under Mediterranean conditions is late heading, caused by day length sensitivity, as evident from phenology and allelic profile (PPD and VRN). Bread wheat is free-threshing, while spelt lines are hulled and the chaff is only released in an additional mechanical p rocess[7] These attributes and other spike characteristics are thought to be mainly controlled by a single pleiotropic gene (Q, chromosome 5A)[8,9]. A recent study suggested that the Q gene might influence the naked grain characteristics[11]

Objectives

Methods

Results

Discussion

Conclusion