Abstract
This study was conducted to clarify the effects of leaf blade or top (containing leaf blade and leaf sheath) pruning in 6 leaf aged rice seedlings on transplanting injury, rooting and early growth after transplanting in comparison with the effects of root pruning. Pruning of whole leaf blade or top less than 50% in dry weight in seedling hardly affected transplanting injury as expressed by leaf emergence rate just after transplanting. However, in leaf-pruned seedlings, rooting or early growth after transplanting was inversely proportional to the extent of leaf pruning, because of the delayed development and growth of new roots and tillers caused by the lesser amount of carbohydrate in the top part of seedlings and the increase of its distribution to leaf blade. These results was striking contrast to those of root-pruned seedlings. Consequently, there was no parallel relationship between transplanting injury and rooting or early growth after transplanting among the seedlings damaged at different parts. Seedlings with completely pruned leaf blade and root exhibited lesser transplanting injury as compared with the seedlings with pruned roots, and took roots faster than leaf blade-pruned seedlings just after transplanting.
