Abstract
To compare the growth, yielding ability and water consumption in the two cultivated rice specks, Oryza sativa L. and O. glaberrima Steud., the respective six strains of O. sativa and O. glaberrima collected in West Africa were examined. O. glaberrima tended to be larger in leaf area at heading time than O. sativa. In some strains of O. glaberrima, the vegetative growth was expanded notably under manuring, and also the panicle number per hill was significantly larger and the one-grain weight significantly smaller than in O. sativa. These two significant differences are correlated with the fact that many strains of O. sativa had long culm and that all strains of O. sativa belong to the javanica type with a large grain. No difference was observed in the grain number per head and the percentage of ripened grains between the two species. The grain yield tended to be larger in O. glaberrima than in O. sativa. On the other hand, O. glaberrima was found to have smaller water use efficiency with greater water consumption.
