Correlation between hordatine accumulation, environmental factors and genetic diversity in wild barley (Hordeum spontaneum C. Koch) accessions from the Near East Fertile Crescent

Abstract

Wild barley shows a large morphological and phenotypic variation, which is associated with ecogeographical factors and correlates with genotypic differences. Diversity of defense related genes and their expression in wild barley has been recognized and has led to attempts to exploit genes from H. spontaneum in breeding programs. The aim of this study was to determine the variation in the accumulation of hordatines, which are Hordeum-specific preformed secondary metabolites with strong and broad antimicrobial activity in vitro, in 50 accessions of H. spontaneum from different habitats in Israel. Differences in the accumulation of hordatines in the seedling stage were significant between different H. spontaneum genotypes from different regional locations and micro-sites. Variation in the hordatine accumulation within genotypes was between 9% and 45%, between genotypes from the same location between 13% and 38%, and between genotypes from different locations up to 121%. Principal component analysis showed that water related factors explain 39%, temperature related factors explain 33% and edaphic factors account for 11% of the observed variation between the populations of H. spontaneum. Genetic analysis of the tested accessions with LP-PCR primers that are specific for genes involved in the biosynthetic pathway of hordatines showed tight correlations between hordatine abundance and genetic diversity of these markers. Multiple regression analyses indicated associations between genetic diversity of genes directly involved in hordatine biosynthesis, ecogeographical factors and the accumulation of hordatines.

Genomics of crop wild relatives: expanding the gene pool for crop improvement

“…the wild progenitor of cultivated barley is found in large populations in the wild (Figure a). Traits that have been identified in or sourced from wild barley ( H. spontaneum ) include Fusarium (crown rot) resistance (Chen et al ., ), selenium concentration (Jun et al ., ), grain hardness (Li et al ., ), sodium accumulation (Shavrukov et al ., ), leaf stripe resistance gene (Biselli et al ., ), stress environments (Ceccarelli, ; Lakew et al ., , ), resistance to powdery mildew and leaf rust (Schmalenbach et al ., ), agronomic traits under postanthesis drought (Kalladan et al ., ), resistance to leaf scald (Friedt et al ., ), salt tolerance (Pakniyat and Namayandeh, ), accumulation of hordatines (Batchu et al ., ) andexotic QTL alleles (Korff et al ., ). Another wild barley species ( Hordeum bulbosum ) has also been used for leaf rust and powdery mildew resistance (Pickering et al ., ), resistance to scald (Pickering et al ., ) and abiotic stress tolerances (Morrell and Clegg, ).…”

Ecologically diverse and distinct neighbourhoods trigger persistent phenotypic consequences, and amine metabolic profiling detects them

“…Hydroxycinnamoyl conjugates of agmatine are antifungal in several Poaceae (Batchu et al . ). The physiological roles of aromatic amines remain less well understood in plants; however, some play roles in plant development and growth (Christou & Barton ; Kulma & Szopa ; Pelagio‐Flores et al .…”

Geography of Genetic Structure in Barley Wild Relative Hordeum vulgare subsp. spontaneum in Jordan

“…Past studies have investigated the correlation between genetic diversity and environment in Spontaneum . They have documented an association between genetic diversity, at single loci, and geography, acrosstemperature or rainfall gradients [ 44 , 49 , 52 , 58 – 61 ]. Genetic differentiation has also been shown to occur, in sympatry, between opposing slopes in the Evolution Canyon in Israel.…”