Genetic control of common bean (Phaseolus vulgaris) resistance to powdery mildew (Erysiphe polygoni)

Abstract

Genetic control of common bean (Phaseolus vulgaris) resistance to powdery mildew (Erysiphe polygoni) was studied using segregating populations from the bean variety crosses Jalo x ESAL 686 and ESAL 550 x ESAL 686. F2 plants, together with the parents, were inoculated and evaluated using a scale of values from one (plant without symptoms) to nine (completely infected plant). F2 plants were harvested individually, and F2:3 families were obtained. These families were evaluated in an 11 x 11 and 12 x 12 simple lattice statistical design for the Jalo x ESAL 686 and ESAL 550 x ESAL 686 crosses, respectively, using the same value scale as the F2 generation. The segregation observed in F2 plants and F2:3 families indicated that two genes are involved in genetic control, due to a double recessive epistasis. The high linear regression coefficient (b) between F2 plants and their F2:3 family, 0.66 for ESAL 550 x ESAL 686 cross, and 0.71 for Jalo x ESAL 686 cross, showed that the trait is highly heritable.<br>Para estudar o controle genético da resistência ao oídio (Erysiphe polygoni) no feijoeiro foram utilizadas as populações segregantes dos cruzamentos Jalo x ESAL 686 e ESAL 550 x ESAL 686. As plantas F2 desses cruzamentos, juntamente com os parentais, foram inoculadas e avaliadas utilizando-se uma escala de notas de 1 (planta sem sintoma) a 9 (planta completamente infectada). As plantas F2 foram colhidas individualmente e obtidas as famílias F2:3. Essas famílias foram avaliadas nos delineamentos látice simples 11 x 11 e 12 x 12 para os cruzamentos Jalo x ESAL 686 e ESAL 550 x ESAL 686, respectivamente, utilizando-se a mesma escala de notas da geração F2. As segregações observadas nas plantas F2 e nas famílias F2:3 indicam que no controle genético estão envolvidos dois genes, sendo este um caso de epistasia recessiva dupla. O coeficiente de regressão linear (b) entre a planta F2 e sua família F2:3 mostrou que o caráter possui alta herdabilidade

Genome-wide Identification of Powdery Mildew Resistance in Common Bean

“…Disease severity was higher in 2018 with maximum disease severity score of 9 compared to 2017 with a maximum disease severity score of 6 among 206 genotypes (5 genotypes were lost during experiments) ( Table 2). However, based on analysis of variance (ANOVA), the heritability of PM resistant trait was 0.69 in this collection, which is consistent with the result of 0.66 and 0.71 in two F 2 populations reported by [28]. Disease severity of PM under natural infection was negatively correlated with yield at r=-0.24 (data not shown), indicating that PM had a signi cant effect on yield of common bean.…”

Identification of resistance to rust (Uromyces appendiculatus) and powdery mildew (Erysiphe diffusa) in Portuguese common bean germplasm

“…For powdery mildew, unlike rust, very few sources of resistance have been described so far, and only qualitative resistance governed by single genes was reported (Zaumeyer and Meiners , Rezende et al. , Trabanco et al. ).…”

“…(Rezende et al. ), but recent studies suggest that it is closer to Erysiphe diffusa (Cooke & Peck) U. Braun & S. Takam, formerly Microsphaera diffusa Cooke & Peck. (Almeida et al.…”

Genome-wide Identification of Powdery Mildew Resistance in Common Bean

“…Powdery mildew (PM) is one of the most ubiquitous plant diseases and it infects a variety of legumes, including green, runner, long and Italian beans, and snow pea in tropical and subtropical regions. PM disease in common bean caused by pathogen Erysiphe polygoni DC [2] accounts for extensive damage and signi cant yield losses 69% prior to owering [3]. Warm temperatures (20-24℃), low humidity and shade.…”