两系亚种间杂交早稻干物质积累分配特性研究

Studies on Accumulation and Distribution of Dry Matter of Two-line Intersubspecific Hybrid Rice

根据测定分析，初步表明两系法亚种间杂交早稻组合干物质积累量大，且具有明显的中、后期优势，尤以生育后期优势显著。干物质的分配较合理，根系和穗部干物质量显著高于常规稻。叶面积适中。

Using Anxiang S/Zhuxuan 173, an early two-line intersubspecific rice hybrid and Xiangzhaoxiang 20 (CK), an early conventional rice variety, as the materials the characterstics of dry matter accumalation and distribution of two-line intersubspecific hybrid rice was studied. The results showed that the dry matter of early two-line intersubspecific hybrid rice accumulated much more with its total dry matter weight tested on the 3rd day before maturity at 13.51 t/hm 2, 20.8% higher than that of the conventional rice variety with the same maturity, the dry matter accumulation of the hybrid combination was obviously superior to that of the conventional variety in the middle and late growth stages, the distribution of dry matter of different organs in hybrid rice was more rational and its panicle dry matter weight increased quickly and up to 8.13 t/hm 2 before maturity, 25% more than that of the conventional rice. Futhermore, the development of root system and the leaf area of hybrid rice were better, and the photosynthetic efficiency in the late growing period was higher. Therefore, the theoretical grain yield of rice hybrid was 20% higher than that of the conventional variety.