Abstract: The root developmental morphology of Teyou 63 with different yield levels was studied to probe ideal root type of super high yielding rice Results showed that:The amount of rice root system decreased as negative exponential curve with the deepening of soil layers at ripen stage and the curve was asympotic to x-axis;The rice plants with 12 t·hm^-2 super high grain yield possessed larger root,dry matter weight (DMW), root volume, total root length and much more developed branch roots in each soil layer within 20cm,the roots densely distributed in soil;Shoot and root DMW increased with the growth of grain yield, but the growth rate of root DMW was lower than that of shoot,and this led to enlarged rate of top to root (T/R) and root activity, therefore,this maintained overall balance of the morphology and function of rice shoot and root;The contribution rate of the upper layer root (0-5cm) to the formation of super high yielding amounted to 65% and that of the lower layer root (5-20cm) to 35%.

Key words: Rice, Super high yielding, Root system, Morphological development