两系杂交水稻C两优系列组合的高产根系特征

Root Characteristics of High-Yield C Liangyou Rice Combinations of Two-Line Hybrid Rice

【目的】揭示两系杂交水稻C两优系列组合的高产根系特征及根系与产量之间的关系。【方法】用两用核不育系C815S配制7个杂交组合,以汕优63为对照,对其根系形态和生理特性及其与产量的关系进行了研究。【结果】C两优系列组合的根系干重、不定根条数、不定根总长、根系总体积、发根力、根系总吸收面积、根系活跃吸收面积和根系a-NA氧化量显著高于对照汕优63。相关分析表明,抽穗期根系干重、不定根条数、不定根总长、根系总吸收面积、根系a-NA氧化量及灌浆期和乳熟期的发根力与单株产量呈极显著或显著正相关。逐步回归表明,抽穗期的不定根数量和根系a-NA氧化量是影响水稻高产的主要因素,可作为水稻高产栽培和水稻品种遗传改良的可靠指标。【结论】C两优系列杂交组合在整个生育期内比汕优63具有发达的根系和较强的根系活力,保证了其营养元素和水分的吸收,从而为高产奠定了基础。尤其是在生育后期仍保持较强的根系活力及地下部与地上部的和谐关系是其高产的重要原因。

【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.