稻草中非结构性碳水化合物不同组分的含量与分布

Content and distribution of nonstructural carbohydrates compositions in different parts of rice(Oryza sativa L.)straw

稻草中非结构性碳水化合物(NSC)是影响稻草青贮品质的重要性状。本研究利用籼稻黄华占和粳稻南粳9108研究稻草不同部位NSC不同组分的含量与分布,为改善稻草青贮品质提供依据。结果表明:南粳9108稻草中NSC含量极显著高于黄华占(P<0.01);黄华占基部茎秆、中部叶鞘和上部叶片,南粳9108基部茎秆、叶鞘和叶片是NSC在植株中的主要贮存部位。黄华占倒1节叶鞘和倒2节茎秆NSC组分中淀粉占比较高,而南粳9108倒3节茎秆淀粉含量显著高于其他部位(P<0.05)。稻草中可溶性淀粉含量占淀粉含量的比例均较低,这意味着稻草中大部分淀粉在青贮过程中难以被水解为发酵底物。在兼顾稻谷生产的前提下,调控稻草中NSC的组分是改善稻草青贮品质的可行手段。

The nonstructural carbohydrates(NSC)are important for the fermentation quality of rice(Oryza sativa L.)straw silage.In this study,the contents and distributions of NSC compositions in different parts of rice straw were studied by using indica variety Huanghuazhan and japonica variety Nanjing 9108,so as to provide the basis for improving the silage quality of rice straw.The results showed that the content of NSC in Nanjing 9108 rice straw was significantly higher than that in Huanghuazhan(P<0.01).The basal stem,middle leaf sheath and upper leaf of Huanghuazhan,and the stem,leaf sheath and leaf at the basic node of Nanjing 9108 were the main parts for NSC storage in plant.For Huanghuazhan,the ratios of starch in NSC compositions in the top 1^(st) sheath and the top 2^(nd) stem were relatively high,while the starch content in the top 3^(rd) stem was significantly higher than that in other parts of Nanjing 9108(P<0.05).In the rice straw of Huanghuazhan and Nanjing 9108,the proportion of soluble starch content in total starch content was low.Those results suggested that most part of starch in rice straw was difficult to be hydrolyzed into fermentation substrate during ensiling.Therefore,under the premise of cansidering rice production,regulating the NSC compositions in rice straw is a feasible means to improve its silage quality.