Genetic changes accompanying the domestication of Pisum sativum: is there a common genetic basis to the 'domestication syndrome' for legumes?
OBJECTIVE
The changes that occur during the domestication of crops such as maize and common bean appear to be controlled by relatively few genes. This study investigates the genetic basis of domestication in pea (Pisum sativum) and compares the genes involved with those determined to be important in common bean domestication.


METHODS
Quantitative trait loci and classical genetic analysis are used to investigate and identify the genes modified at three stages of the domestication process. Five recombinant inbred populations involving crosses between different lines representing different stages are examined.


RESULTS
A minimum of 15 known genes, in addition to a relatively few major quantitative trait loci, are identified as being critical to the domestication process. These genes control traits such as pod dehiscence, seed dormancy, seed size and other seed quality characters, stem height, root mass, and harvest index. Several of the genes have pleiotropic effects that in species possessing a more rudimentary genetic characterization might have been interpreted as clusters of genes. Very little evidence for gene clustering was found in pea. When compared with common bean, pea has used a different set of genes to produce the same or similar phenotypic changes.


CONCLUSIONS
Similar to results for common bean, relatively few genes appear to have been modified during the domestication of pea. However, the genes involved are different, and there does not appear to be a common genetic basis to 'domestication syndrome' in the Fabaceae.
Department of Plant Sciences and Plant Pathology, Montana State University, Bozeman, MT, USA. nweeden@montana.edu
Norman F
NF
Weeden
D000383:Agriculture; D001947:Breeding; D002874:Chromosome Mapping; D018556:Crops, Agricultural / Q000235:genetics*; D017343:Genes, Plant; D009154:Mutation; D018532:Pisum sativum / Q000235:genetics*; D027805:Phaseolus / Q000235:genetics; D040641:Quantitative Trait Loci; D012641:Selection, Genetic