|Porch, Timothy - Tim|
Submitted to: Journal of Agriculture of the University of Puerto Rico
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/27/2004
Publication Date: 12/20/2004
Citation: Porch, T.G., Dickson, M.H., Long, M.C., Viands, D.R., Jahn, M. 2004. GCA effects of reproductive heat tolerance in snap bean. Journal of Agriculture of the University of Puerto Rico. v. 88(3-4):161-164. Interpretive Summary: High temperatures during flowering reduce seed yield in common bean. Yield losses due to temperature stress are a growing concern in both tropical and temperate zones because of global climate change and the extension of agriculture to lower altitudes in the tropics. This study investigated snap bean varieties that respond differently to high temperature stress. The results indicate that there are significant genetic differences in how many pods each variety produces after experiencing heat stress. These differences between varieties are consistently inherited in their progeny and can, therefore, be used to select those progeny with the highest yields under heat stress. The genetically superior varieties from this study can be used for improving the tolerance of beans to high temperature stress by plant breeders. In addition, the knowledge about the genetics of heat tolerance gained from this study can be used in plant genetics anad molecular biology for the development of novel approaches to improve tolerance to high temperature stress.
Technical Abstract: High ambient temperatures are an increasingly important constraint to crop production in the lowland tropics due to global warming and the extension of the agricultural frontier to lower altitudes. The objective of this study was to determine genetic combining abilities for heat tolerance in common bean (Phaseolus vulgaris L.) germplasm. A fixed-effects 10-parent diallel analysis was conducted under high temperature conditions with Andean genotypes. The resulting data were analyzed using ordinary least squares equations. Positive general combining ability (GCA) effects were found for pod number and several lines previously selected for cold tolerance showed positive GCA effects for heat tolerance.