超级杂交稻持续增产的茎秆维管束结构基础研究

Study on the Characterization of Stem Vascular Bundles in Super Hybrid Rice with Yield Potential Continuous Increase

为探究不同产量潜力超级杂交稻持续增产的茎秆维管束结构基础,以具有不同产量潜力的4期超级杂交稻代表性品种两优培九、Y两优1号、Y两优2号和Y两优900为材料,在大田栽培条件下,研究了4期超级杂交稻茎秆维管束结构的差异及其与产量和产量构成因素间的关系。结果表明:随产量潜力的提高,4期超级杂交稻各节间大、小维管束数目均表现出不断增加的变化趋势,除倒5节小维管束面积和总面积表现为先升高后降低、倒2节和倒3节大维管束面积和总面积表现为先降低后升高外,其他节间大、小维管束面积和总面积均表现为不断增加的变化趋势。随着产量潜力的增加,4期超级杂交稻的实际产量、穗粒数均表现出不断增加的趋势,第4期超级杂交稻(Y两优900)较第1期超级杂交稻(两优培九)增产68. 83%,穗粒数增加87. 42%,而有效穗数呈逐渐减少的变化趋势,千粒质量和结实率则表现为先升高后降低的趋势。相关分析表明,茎秆维管束结构特征与穗粒数、结实率以及产量存在正相关,而与千粒质量存在负相关,特别是上部茎节间小维管束和基部茎节间大维管束结构特征显著影响超级杂交稻产量及产量构成要素。因此,4期超级杂交稻上部茎节间小维管束结构特征以及基部节间大维管束结构特征的改善是保证超级杂交稻产量潜力不断提高、穗大粒多和结实率正常的前提。

In order to explore the stem vascular bundle structure of different yield potential super hybrid rice,the four-stage super hybrid rice representative varieties: Liangyoupei 9,Y Liangyou 1,Y Liangyou 2,and Y Liangyou 900 were used to study the differences of stem vascular bundle structure and its relationship with yield and its competent factors under field cultivation conditions. The results showed that: the number of small and large vascular bundles in each internode increased with the increased of yield potential of the four-stage super hybrid rice. The area and total area of small and large vascular bundle showed an increasing trend,except for the fifth internode small vascular bundle showed increased firstly and then decreased and the second and third internode large vascular bundle showed decreased firstly and then increased with the increased of yield potential. Furthermore,the yield and spikelets per panicle were increased with the yield potential increased of the four-stage super hybrid rice. Compared with Liangyoupei 9,yield and spikelets per panicle of Y Liangyou 900 increased 68. 83% and 87. 42%,respectively.Whereas the effective panicles showed a reverse trend,the 1000-grain weight and seed setting rate showed a trend of increased firstly and then decreased with the increased of yield potential. Correlation analysis showed that the characterization of stem vascular bundles not only positive correlated with the number of grains per panicle,seed setting rate and yield,but also negative correlated with 1000-grain weight,especially for the characterization of small stem vascular bundles at the top part and large stem vascular bundles at the basal part showed significantly correlated with the yield and its competent factors in super hybrid rice. Therefore,the yield potential increased,bigger panicle with more spikelets,and normal seed setting rate of the four-stage super hybrid rice might result from the improvement of the small stem vascular bundles at the top part and large stem vascular bundles at the basal part of the stem.