Author
POSA-MACALINCAG, M - MICHIGAN ST UNIVERSITY | |
Hosfield, George | |
GRAFTON, KENNETH - NORTH DAKOT ST UNIVERSITY |
Submitted to: American Society for Horticultural Science
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 4/8/2002 Publication Date: N/A Citation: N/A Interpretive Summary: Canning quality in dry bean is a complex trait and is made up of a number of individual components. The component properties of canning quality are inherited quantitatively, i.e., the measurements do not fall into discrete groupings but are continuous along a scale. In quantitative trait analysis, the use of markers and genetic maps permit the breeder to identify regions of an organism's DNA that contain genes influencing a particular trait. The discovery of DNA markers called RAPDs associated with component properties of canning quality will be useful as an aid to selection in a bean breeding program. Accordingly, an experiment was conducted to find RAPD markers linked to the major genes (QTL) affecting the expression of split beans (SPLT) and visual appeal (APP) after canning. Two populations consisting of kidney bean breeding lines were evaluated for SPLT and APP in six year-location combinations in Michigan, Minnesota, and North Dakota over four years. Population 1 was from a cross between 'Montcalm', a dark red kidney bean with excellent canning quality, and 'California Dark Red Kidney', a variety with unremarkable canning quality. Population 2 was derived from 'Montcalm' and 'California Early Light Red Kidney' a variety with poor canning quality. The RAPDs were screened against each line in Population 1 and markers linked to QTL influencing canning quality were tested for their utility in population 2. In population 1, seven RAPDs were linked to a QTL associated with a low number of SPLT and a high APP score. The QTL region associated with these markers mapped to the B8 linkage group of the core bean linkage map. Desirable canning quality of the QTL in Population 1 was derived from 'Montcalm', but interestingly, desirable canning quality in Population 2 was derived from 'California Early Light Red Kidney' kidney bean. Since the DNA used to screen for RAPD markers is taken from the leaves of seedling plants and not the seeds, a breeder can screen for canning quality without ever having to can the beans. The canning process is energy consumptive and requires large quantities of water for soaking and blanching beans before they are put into cans. Thus, the use of RAPD markers in breeding for canning quality saves time and money and protects the environment because of the elimination of water that would be used if the beans were canned. Technical Abstract: Canning quality of dry bean (Phaseolus vulgaris L.), of which the degree of splitting (SPLT) and overall appearance (APP) if canned beans are major components, is a complex trait that exhibits quantitative. The objectives of this study were to identify major genes that affect APP and SPLT in kidney bean, and map the location of these loci to the integrated core map of common bean. The analysis was performed using random amplified polymorphic DNA (RAPD) markers and two populations of kidney bean, consisting of 75 and 73 recombinant inbred lies (RILs), respectively. The two populations-'Montcalm' x 'California Dark Red Kidney 82' and 'Montcalm' x 'California Early Light Red Kidney'-were planted in six year-location combinations in Michigan, Minnesota, and North Dakota from 1996 to 1999. Correlations between APP and SPLT were high (0.91 to 0.97). Heritability estimates for APP and SPLT ranged from 0.83 to 0.85 in the two populations. Major genes for these traits were identified on two linkage groups. The first QTL, associated with seven RAPD markers, was putatively mapped to the B8 linkage group of the core bean linkage map. Desirable canning quality appeared to be derived from Montcalm at this locus. The second QTL, associated with four markers, appeared to be derived from the California parents. The second linkage group was not assigned to a linkage group in the core map. Population and environment-specificity were observed for the markers identified. |