• Asian-Australasian Journal of Animal Sciences
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• v.13 no.4
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• pp.431-434
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• 2000

Maintaining maximum genetic variability is of critical importance with in-situ conservation of animal species in small populations. Marker-assisted mating (MAM) was suggested to achieve maximum heterozygosity in offspring populations. The aims of this research was to investigate and decide the effectiveness and promising types of MAM to achieve this goal. Analysis of variance with simulation data revealed that the heterozygosity in offspring populations was significantly determined by sire heterozygosity from mating of non-inbred parent animals, and significantly by sire heterozygosity and percent parental difference in offspring reproduced by inbred parents. Seven types of marker-assisted mating schemes were examined, in which offspring exhibited heterozygosity that was -0.01 to 7.37% below or above that from random mating of non-inbred parent animals, and 0.00 to 16.39% above that from random mating of inbred parent animals. The great increase in offspring heterozygosity was observed with mating by tandem maximizing sire heterozygosity, percent parental difference, and dam heterozygosity. Random mating resulted in fluctuation of offspring heterozygosity. These results suggested that MAM was a promising method for maintaining maximum offspring variability in in-situ conservation of animal species in small populations.

• Journal of Life Science
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• v.7 no.4
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• pp.358-360
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• 1997

Soybean [Glycine max (L.) Merr.] seed size is a important yield component and is a primary consideration in the development of cultivars for specialty markets. Our objective was to examine the consistency of QTLs for seed size across generations. A 68-plant F$_{2} segregation population derived from a mating between Marcury (small seed) and PI 467.468 (large seed) was evaluated with RAPD markers. In the F$_{2} plant generation (i.e. F$_{3} seed), three markers, OPL09a, OPM)7a, and OPAC12 were significantly (P<0.01) associated with seed size QTLs. In the F$_{2} ; F$_{3} generation (i.e., F$_{4} seed), four markers, OPA092, OPG19, OPL09b, and OPP11 were significantly (P<0.01) associated with seed size QTLs. Just two markers, OPL09a, and OPL09b were significantly (P<0.05) associated with seed size QTLs in both generations. The consistency of QTLs across generations indicates that marker-assisted selection for seed size is possible in a soybean breeding program.