Abstract: Plant height of the rice infected with rice black-streaked dwarf virus （RBSDV） varied significantly in different developing periods of black-streaked dwarf disease. Based on the correlation， five types of diseased plants were divided according to the different levels of plant height. Production per plant， effective tiller number， spike length， empty grains rate and thousand kernel weights of diseased rice plants were determined. Using the DPS software， the correlations between each value of parameters above and the type were analyzed; and values between different types were compared. The results showed that production per plant， effective tiller number， spike length and thousand kernel weights reduced as the dwarf increased while empty grains rate increased. Furthermore， significant differences were showed among different types of diseased rice.

Key words: RBSDV, type, dwarf level, effective tiller, thousand kernel weight