Segregation for performance in recombinant inbred populations resulting from inter-gene pool crosses of common bean ( Phaseolus vulgaris L.) |
| |
Authors: | William C Johnson Paul Gepts |
| |
Institution: | (1) Department of Agronomy and Range Science, University of California, One Shields Avenue, Davis, CA, 95616-8515, U.S.A. |
| |
Abstract: | The germplasm of cultivated common bean exhibits a lower level of genetic diversity within each geographical gene pools (Mesoamerican
and Andean) compared to that of the respective wild ancestors. Crosses between these two gene pools potentially provide a
source of additional genetic diversity but their progenies have been characterized by phenotypic abnormalities and reduced
productivity. In order to gain additional insights into this problem, we examined the segregation for performance in two recombinant
inbred populations (RIPs) resulting from Mesoamerican × Andean crosses in three contrasting environments and two years. The
two RIPs – ‘California Dark Red Kidney’ (of Andean origin) × ‘Yolano’ (Mesoamerican), n = 150, and A55 (Mesoamerican) × G122
(Andean), n = 67 – were grown in replicated field tests to assess the agronomic performance of each recombinant inbred line.
Both populations exhibited, on average, greater days to maturity (DTM), lower biomass growth rate (above-ground dry weight/DTM),
lower economic growth rate (seed yield/DTM), and lesser harvest index. In contrast with the conclusions of earlier experiments,
there was no evidence from the field trials for a genetic association (due to linkage or pleiotropy) between seed weight and
economic growth rate, but there may be a genetic association between seed weight and life cycle length. We compare the results
of these studies with earlier experiments on inter-gene pool recombinant populations of common beans and relate our observations
of diminished performance to models of speciation mechanisms.
This revised version was published online in July 2006 with corrections to the Cover Date. |
| |
Keywords: | exotic germplasm growth rate introgression seed weight speciation yield |
本文献已被 SpringerLink 等数据库收录! |
|