Abstract
In order to get the basic informations regarding the rice breeding materials which are suitable at the whole parts in Korea, eighteen varieties which composed by 4 Indica cultivars, 2 upland rice varieties, 2 waxy Japonica cultivars, 2 direct seeding cultivars, 2 coloured rice cultivars, 5 native rice varieties and standard variety were grown at the Sangji University from May 1998 to October 1998. Yield and yield component's elements. harvest index and productivity score were investigated at the maturity stage and post harvest. Grain yield, straw yield and number of spikelets per panicle which had a great variance by the variance analysis were anticipated for the impact of selection and the possibility of character improving, and these characters had a great heritability, more than 90%. Ripened grain ratio and 1000 grain weight which had a low heritability, less than 42%, affected so much by the environmental elements such as temperature and solar radiation etc. The genetic correlation coefficient showed greater than phenotypic correlation coefficient in all investigated characters. The ripened grain ratio which had great environmental correlation than genetic and phenotypic correlation much effected by the environmental elements. Grain yield showed a great positive significant genetic and phenotypic correlations with the number of panicles per hill, number of spikelets per panide. harvest index and productivity score. In case of harvest index and productivity score at the environmental correlation coefficients showed highly positive correlation with grain yield.