抄録
In addition to the common cultivated rice, O. sativa L., there occurs in Western Africa lanother cultivated rice species, O. glaberrima STEUD. They have the same chromosome number and the pairing of chromosomes in their F1 hybrids is normal. For looking into problerns relative to the phylogenetic make-up of these rice species, variations and correlations in various characters observed in O. glaberrima were compared with those in O. sativa, using a nurnber of varieties of both. It was found that O. glaberrima forms a distinct group represented by a short and tough ligule, death after maturity, pronounced seed dormancy, and weakness to drought, though in other characters, the two species Observing showed overlapping variation ranges and similar patterns of correlations. pollen fertilities of many F1 hybrids, it was found that the two species were almost completely separated by hybrid sterility. The writers have looked for intermediate plants
