Abstract:

【Objective】 The root characteristics of C Liangyou rice combinations and the correlation between root characteristics and yield were studied. 【Method】 The root morphology, root physiology as well as the correlation between root characteristics and yield were studied by using seven C Liangyou rice combinations as experimental materials and Shanyou 63 as a control. 【Result】 The results showed that root dry weight, number of adventitious root , total length of adventitious root, total root volume, root growth abilities, total root absorption area,root active absorption area and root oxidation ability of the combination were significantly higher than those of the control Shanyou 63. Root dry weight, number of adventitious root , total length of adventitious root, total root absorption area,and root oxidation ability at the heading stage, and root growth abilities at the grain filling stage and the milking stage had a significant positive correlation with yield per plant. Stepwise regression indicated that the number of adventitious root and root oxidation ability at the heading stage were the main influencing factors of high yield of rice and could be regarded as reliable indicators for cultivation and management and genetic inprovement of rice. 【Conclusion】 It is concluded that root morphology is good and the root is vigorous in C Liangyou rice combinations at all stages, its morphological and physiological characteristics ensure the efficient absorption of nutrient and water in the whole growing period, which is the base leading to high yield of C Liangyou rice combinations. Strong root vigor at the late growing stage, and proper ratio of root to shoot and the harmonious growth of root and shoot are also the main causes leading to high yield of C Liangyou rice combinations.

Key words: hybrid rice (Oryza sativa L.), root morphology, root physiology, yield, correlation