This study was carried out to investigate the relationship between resistance to brown planthopper (Bph) and some agronomic characters of rice using two japonica RIL_s (F₄) of Milyang 95/Milyang 64 and Milyang 165/Milyang 64. Culm len

Two rice varieties, 'Oochikara' with large grain and 'Hwayeongbyeo' and their progenies (F1 , F2 , B1 and B2 ) were tested to understand gene action of morphological traits of rice grain and their relationships. The evaluated traits were 1,000-grain weight, grain length, width, thickness, length-width ratio and chalkiness of brown rice. Correlation between grain weight and chalkiness was highly significant in the all progenies, and grain length were not associated with width and thickness in an F2 population. Scaling test and jonit scaling test revealed that inheritance of grain traits were fitted to additive-dominance model without epistasis. Additive effects for the traits were much greater than the dominance effects.