Barley Traits Associated with Resistance to Fusarium Head Blight and Deoxynivalenol Accumulation

Abstract

Fusarium head blight (FHB) or scab is a destructive disease of barley in many countries. A better understanding of the interrelationships between plant traits and FHB resistance should help in the development of effective and efficient breeding strategies for FHB-resistant cultivars. Recent mapping studies indicate that many of the quantitative trait loci (QTL) for FHB resistance coincide with the QTL for plant height, heading date, and spike characteristics. Therefore, a study was conducted to investigate the relationship of morphological and physiological traits to FHB infection and deoxynivalenol (DON) accumulation in a barley doubled-haploid (DH) population derived from a Léger x CI9831 cross. Approximately 190 DH lines were grown at Ottawa (Ontario) for 2 years, Charlottetown (Prince Edward Island) for 1 year, and Hangzhou (Zhejiang) for 2 years. The field plots were inoculated with Fusarium graminearum at each location. FHB incidence was positively correlated with DON content. Resistance to FHB was associated with two-row spike, purple lemma, long glume awn, tall stature, and resistance to lodging, but it was not associated with long rachilla hairs, rough lemma awn, or heading date. Two-row spike was associated with tall stature and resistance to lodging. These associations as well as its spike characteristics helped reduce FHB infection and DON accumulation in two-row lines compared with six-row lines. The association between long glume awn and FHB resistance could be due to genetic linkages. Therefore, trait associations should be taken into consideration when breeding for FHB resistance and interpreting data from FHB experiments.

Evaluation of Canadian barley breeding lines for Fusarium head blight resistance

“…A similar correlation has also been reported in barley studies (de la Pena et al 1999;Zhu et al 1999;Ma et al 2000;Choo et al 2004), including the present research, in which PH was significantly negatively correlated with all FHB parameters except DON2013. Nevertheless, it may not be difficult to select short resistant lines, considering the moderate to low correlation coefficients (Table 3).…”

Resistance against Fusarium graminearum and the relationship to β-glucan content in barley grains

“…Negative correlations between spike resistance and toxin accumulation have also been reported by other authors (e.g. Tekauz et al 2000;Choo et al 2004;Berger et al 2014;He et al 2015). Yet, the present results show that DON content is not linked with the colonization of the grain by FG.…”

“…BWaxyma^was the most resistant variety with respect to DON accumulation and second to BCassia^in all other categories. In contrast to six-row varieties, two-row spikes may impede the external propagation of the pathogen from one spikelet to the other (Choo et al 2004;Langevin et al 2004), Even though in BCassia^and BWaxyma^both spike and grain resistances are present, results of the less resistant genotypes show that the two resistance types are acting independently. The degree of colonisation of the grain was linked to the reduction of grain filling but not linked with accumulation of DON.…”

Development and Genetic Characterization of an Advanced Backcross-Nested Association Mapping (AB-NAM) Population of Wild × Cultivated Barley

“…This selection will limit our ability to map loci on chromosome 2H, but it will also minimize the confounding effects of phenotyping a population that is segregating for a major morphological trait. This is especially true for assessment of Fusarium head-blight resistance and malting quality, which can be markedly affected by row type (Marquez-Cedillo et al 2000;Choo et al 2004). No other regions of the genome show reduced introgression frequency, but regions on chromosomes 1H and 6H show an overrepresentation of wild barley introgression across the population.…”