|Soltani, Ali - North Dakota State University|
|Bello, Marco - North Dakota State University|
|Mndolwa, Eninka - North Dakota State University|
|Schroder, Stephan - North Dakota State University|
|Moghaddam, Samira - North Dakota State University|
|Osorno, Juan - North Dakota State University|
|Miklas, Phillip - Phil|
|Mcclean, Phillip - North Dakota State University|
Submitted to: Crop Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/14/2016
Publication Date: 10/6/2016
Citation: Soltani, A., Bello, M., Mndolwa, E., Schroder, S., Moghaddam, S., Osorno, J., Miklas, P.N., McClean, P. 2016. Targeted analysis of dry bean growth habit: Interrelationship among architectural, phenological and yield components. Crop Science. 56:3005-3015.
Interpretive Summary: Dry bean breeding is useful for developing cultivars with improved traits desired by bean growers. One such trait desired by growers is upright architecture, with pods distributed throughout the plant canopy, and combined with high yield. This combination of traits is referred to as the ideotype. A major component of the dry bean ideotype is upright architecture that is resistant to lodging. Such plants are conducive to direct harvest vs the multistep harvesting process of cutting, windrowing, drying and then combining, and is the major direction the industry is moving toward. To facilitate ideotype breeding in common bean we characterized 192 breeding lines for traits associated with upright architecture, lodging resistance, and pod distribution (the ideotype). A major heritable component of ideotype was observed to be the simply measured main stem diameter at the soil surface. The stem diameter trait had a high correlation with upright architecture resistant to lodging and may facilitate selection in breeding programs for the grower preferred ideotype.
Technical Abstract: A targeted breeding strategy to improve an economically important trait is achievable if a subcomponent phenotype(s) most associated with the trait is the selection target. Dry bean (Phaseolus vulgaris L.) is an important staple crop, providing crucial nutritious food for direct human consumption. An enhancement in dry bean production was facilitated in the last 25 years by replacing Type III prostrate growth habit with Type II upright growth habit. Importantly this growth habit leads to disease avoidance and enables cost-effective management practices. We characterized sixteen traits at three locations using a panel consisting of 122 genotypes with different growth habits from race Durango of dry bean. An alpha design was used at all locations. Among the growth habit types, significant differences were detected for seven architectural traits, three seed yield traits, and one phenological trait. Genetic variance was greater in the Type III genotypes than the Type II genotypes for six of the significant traits. For Type II genotypes, moderate narrow sense heritability was detected for canopy height, lodging, plant length, and stem diameter suggesting positive gain can be made for growth habit from crosses between Type II genotypes. A network analysis of Type II genotypes revealed these four traits are highly correlated and suggests possible genetic relatedness among the traits. Breeders often use canopy height as a selection criterion, and the positive correlation between this trait and stem diameter suggests a possible anatomical mechanism responsible for the more upright plant types.