Author
URREA, CARLOS - University Of Nebraska | |
Porch, Timothy - Tim |
Submitted to: Bean Improvement Cooperative Annual Report
Publication Type: Research Notes Publication Acceptance Date: 3/15/2010 Publication Date: 3/15/2010 Citation: Urrea, C., Porch Clay, T.G. 2010. Phenotypic evaluation of a subset of the Phaseolus vulgaris core collection, the P. acutifolius germplasm collection and cultivars for drought tolerance in Nebraska and Puerto Rico. Annual Report of the Bean Improvement Cooperative. 53:164-165. Interpretive Summary: Drought stress is an important constraint to common bean production worldwide and is an increasing constraint on US production. In this study, exotic common bean (Phaseolus vulgaris) and tepary bean (Phaseolus acutifolius) germplasm from the NPGS and CIAT collections and from US and international breeding programs were evaluated for their response to drought stress. A total of 277 entries, 128 cultivars and elite lines and 149 accessions of P. vulgaris and P. acutifolius from the NPGS and CIAT core collections, were evaluated under drought stress conditions at Mitchell, NE and at Fortuna, PR. To evaluate plant response to water stress, yield and plant development data were collected. The drought intensity of the trials was moderate based on the reduction in yield in the drought stressed trials. The yield of the accessions from the germplasm collections were lower than the common bean cultivars and germplasm tested, with the exception of PI 476751. The results illustrate that progress has been made in breeding for improved adaptation and drought tolerance in breeding programs. Technical Abstract: Drought stress is an important constraint to common bean production worldwide and is an increasing constraint on US production. In this study, exotic common bean (Phaseolus vulgaris) and tepary bean (Phaseolus acutifolius) germplasm from the NPGS and CIAT collections and from US and international breeding programs were evaluated for their response to drought stress. A total of 277 entries, 128 cultivars and elite lines and 149 accessions of P. vulgaris and P. acutifolius from the NPGS and CIAT core collections were screened under terminal drought stress conditions at Mitchell, NE and at Fortuna, PR. To evaluate plant response to water stress, yield (kg/ha), 100-seed weight (g), and the number of days to flowering and to maturity were determined and the drought intensity index (DII), geometric mean (GM), drought susceptibility index (DSI), and percent yield reduction (PR) were calculated. In the combined analysis, drought intensity index (DII) was moderate (0.34), while yield under non-stress and drought stress ranged from 800 to 2510 kg/ha, and from 596 to 2516 kg/ha, respectively. The yield of the PI accessions (P. vulgaris and P. acutifolius) were lower than the common bean cultivars and germplasm tested, with the exception of PI 476751. The results illustrate that progress has been made in breeding for improved adaptation and drought tolerance in breeding programs. |