Genetic markers associated to arbuscular mycorrhizal colonization in durum wheat

Pasquale De Vita,Anna M Mastrangelo,Luigi Cattivelli,Cristiana Sbrana,Luciano Avio,Giovanni Laidò,Manuela Giovannetti,Daniela Marone

doi:10.1038/s41598-018-29020-6

Abstract

In this work we investigated the variability and the genetic basis of susceptibility to arbuscular mycorrhizal (AM) colonization of wheat roots. The mycorrhizal status of wild, domesticated and cultivated tetraploid wheat accessions, inoculated with the AM species Funneliformis mosseae, was evaluated. In addition, to detect genetic markers in linkage with chromosome regions involved in AM root colonization, a genome wide association analysis was carried out on 108 durum wheat varieties and two AM fungal species (F. mosseae and Rhizoglomus irregulare). Our findings showed that a century of breeding on durum wheat and the introgression of Reduced height (Rht) genes associated with increased grain yields did not select against AM symbiosis in durum wheat. Seven putative Quantitative Trait Loci (QTLs) linked with durum wheat mycorrhizal susceptibility in both experiments, located on chromosomes 1A, 2B, 5A, 6A, 7A and 7B, were detected. The individual QTL effects (r2) ranged from 7 to 16%, suggesting a genetic basis for this trait. Marker functional analysis identified predicted proteins with potential roles in host-parasite interactions, degradation of cellular proteins, homeostasis regulation, plant growth and disease/defence. The results of this work emphasize the potential for further enhancement of root colonization exploiting the genetic variability present in wheat.

Highlights

Arbuscular mycorrhizal fungi (AMF) establish mutualistic symbiotic associations with the roots of most land plants[1] and provide many different agroecosystem services, such as an efficient use of fertilizers and soil nutrients, protection against biotic and abiotic stresses, increased N2 fixation in legume crops and improved soil aggregation[2]
The breeding of crop genotypes able to benefit from AMF could be greatly enhanced by information on susceptibility of cultivated varieties to mycorrhizal colonization, scanty information is available on the influence of host genotype on the establishment of mycorrhizal symbiosis, and in particular on the putative loss of susceptibility of modern vs. old varieties to AMF13,16,17,19,20
We report on a study designed (i) to evaluate the mycorrhizal status of 108 lines of T. turgidum ssp. durum, differing for origin and year of release, using two arbuscular mycorrhizal (AM) fungal species (Funneliformis mosseae and Rhizoglomus irregulare) and (ii) to detect genetic markers in linkage with chromosome regions involved in AM fungal root colonization through genome wide association analyses

Summary

Introduction

Arbuscular mycorrhizal fungi (AMF) establish mutualistic symbiotic associations with the roots of most land plants[1] and provide many different agroecosystem services, such as an efficient use of fertilizers and soil nutrients, protection against biotic and abiotic stresses, increased N2 fixation in legume crops and improved soil aggregation[2]. They enhance plant nutrition by means of extensive mycelial networks which spread from colonized roots and efficiently absorb and translocate mineral nutrients, such as phosphorus (P) and nitrogen (N) from the soil to the host plants[3,4]. We report on a study designed (i) to evaluate the mycorrhizal status of 108 lines of T. turgidum ssp. durum, differing for origin and year of release, using two AM fungal species (Funneliformis mosseae and Rhizoglomus irregulare) and (ii) to detect genetic markers in linkage with chromosome regions involved in AM fungal root colonization through genome wide association analyses

Methods

Results

Conclusion