Author
LINARES, A. - North Dakota State University | |
URREA, C. - University Of Nebraska | |
Porch, Timothy - Tim | |
MAMIDI, SUJAN - North Dakota State University | |
MCCLEAN, P. - North Dakota State University | |
OSORNO, J. - North Dakota State University |
Submitted to: Bean Improvement Cooperative Annual Report
Publication Type: Research Notes Publication Acceptance Date: 7/1/2014 Publication Date: 4/1/2014 Citation: Linares, A.M., Urrea, C.A., Porch Clay, T.G., Mamidi, S., Mcclean, P.E., Osorno, J.M. 2014. QTL mapping for drought tolerance using a RIL population. Bean Improvement Cooperative Annual Report. p. 37-38. Interpretive Summary: The identification of loci associated with drought tolerance is an important strategy for implementing marker assisted selection. In this study, a population of 335 bean lines, derived from the cross between a drought-susceptible pinto cultivar, and a drought-tolerant small red germplasm line were evaluated in non-stress and drought stress trials in Nebraska and in Puerto Rico. The genetic map for the population was generated. Three quantitative trait loci (QTL) for seed yield were found, and additional QTL were identified for agronomic and physiological traits, including six for seed weight and ten for leaf temperature in five environments. With the results from this study, plant breeders will have a better understanding of the genetics and possible mechanisms behind drought tolerance, as well as the possibility of the use of these QTL for genetic improvement. Technical Abstract: The identification of loci associated with drought tolerance is an important strategy for implementing marker assisted selection. In this study, a population of 335 recombinant inbred lines was derived from the cross between ‘Buster’, a drought-susceptible pinto cultivar, and SER 22, a drought-tolerant small red germplasm line were evaluated. Evaluation in replicated non-stress and drought stress trials using an alpha design with commercial and local checks was performed at two locations, in Nebraska and in Puerto Rico. The linkage map comprised a total of 378 single nucleotide polymorphism markers for a total map distance of 778.4 cM divided across twelve linkage groups. Three QTL for seed yield were found on two linkage groups using composite interval mapping. Additional QTL were identified for agronomic and physiological traits, six for 100-seed weight and ten for leaf temperature in five environments. With the results from this study, plant breeders will have a better understanding of the genetics and possible mechanisms behind drought tolerance, as well as the possibility of the use of these QTL for genetic improvement. Validation studies are going to be performed using extreme phenotypes. |