ANALYSIS OF THE RELATIONSHIP BETWEEN LEAF-EMERGENCE DATE AND LENGTH OF ORGANS ON THE MAIN CULM IN RICE PLANT UNDER A GIVEN ENVIRONMENTAL-CONDITION

In order to examine the regularity of shoot development in rice plants , we determined the relationship between leaf-emergence date and the l ength of various organs on the main culm of cv. Koshihikari and Nippon bare under given culturing conditions. (1) The emergence date of the 1 4th leaf correlated in a highly negative manner with the 15th and 16th laminae lengths and the 14th and 15th sheath lengths, however it corr elated in a highly positive manner with the IV and V internode lengths . (2) The plants having 17 leaves on the main culm showed an earlier e mergence of the 14th leaf, longer laminae at the upper position and sh orter internodes at the lower position than those having 16 leaves. (3 ) When the total leaf number was the same, the plants having the longe st laminae at the upper position on the main culm indicated earlier em ergence dates of the 14th leaf, longer laminae at the upper position a nd shorter internodes at the lower position. Even when the emergence d ate of the 14th leaf was the same, longer laminae at the upper positio n and shorter internodes at the lower position were observed on planes having the longest laminae at the upper position.