A Survey of Hybrid Sterility Relationships in the Asian Forms of Oryza perennis and O. sativa

Publisher Website
Google Scholar
Abstract
Study on the sterility relationships in Asian wild rice, Oryza perennis, which could be the progenitor of cultivated rice. The wild strains were mostly inter-fertile and gave fertile F1 hybrids with sativa varieties which were partly inter-sterile. The data for F1 pollen fertility obtained with 5 test-strains were studied by using the technique of principal component analysis: the Asian wild-rice forms have a potentiality to differentiate into Indica and Japonica types, and the differentiation might advance with the approach to the cultivated type. The sterility frequently found in the populations of perennis type was considered to be due to genetic factors with diplontic or zygotic effect. The populations were also found to contain factors responsible for the gametic sterility of F1l hybrids. It was inferred that wild rice carries double-dominant combinations of those duplicate genes, so that it produces fertile F1 hybrids with sativa varieties of different types, which might have become inter-sterile after recessive mutations or deficiencies had taken place at one or the other of those loci. Variations of those genes within populations indicated the potentiality of wild rice to form partly inter-sterile groups.