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Tetrasomic segregation for multiple alleles in alfalfa
1Department of Genetics, the University of Alberta, Edmonton, Alberta, Canada T6G 2E9.
Genetics
|May 1, 1982
Summary
This study provides evidence of tetrasomic inheritance in alfalfa (Medicago sativa L. and M. falcata L.) for multiple codominant alleles. Direct evidence of autotetraploidy and tetra-allelic loci in alfalfa was observed.
Area of Science:
- Plant Genetics
- Molecular Biology
- Agronomy
Background:
- Alfalfa (Medicago sativa L. and M. falcata L.) exhibits complex genetic inheritance patterns.
- Understanding the ploidy level and allelic diversity is crucial for alfalfa breeding and genetic studies.
Purpose of the Study:
- To investigate tetrasomic inheritance in alfalfa for codominant alleles at isozymic loci.
- To provide direct evidence for autotetraploidy and tetra-allelic loci in alfalfa.
- To assess the genetic relatedness of Medicago sativa and Medicago falcata.
Main Methods:
- Starch gel electrophoresis was used to analyze isozymes in seedling root tissue and seeds.
- Segregation of alleles at the Prx-1, Lap-1, and Lap-2 loci was studied in progenies of di-, tri-, and tetra-allelic plants.
- Analysis included crosses of Medicago sativa, Medicago falcata, and their hybrids.
Main Results:
- Tetrasomic inheritance and chromosomal-type segregation were consistently observed for the studied isozymic loci.
- Tetrasomic segregation, including potential double reduction, was noted in a progeny with four different alleles at the Lap-2 locus.
- Direct evidence supporting autotetraploidy and the presence of tetra-allelic loci in alfalfa was obtained.
Conclusions:
- The findings confirm tetrasomic inheritance in alfalfa, supporting its autotetraploid nature.
- The study demonstrates the existence of tetra-allelic loci, contributing to the genetic complexity of alfalfa.
- Genetic data suggest Medicago sativa and Medicago falcata are closely related, potentially representing biotypes of a single species.
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