高产味优粳稻分蘖特性及其与群体生产力的关系

以高产优质粳稻品种南粳5718和中产优质粳稻品种常农粳10号为参试材料，比较研究不同基因型品种分蘖发生与成穗特性的蘖位差异，明确高产味优基因型品种的优势叶位。结果表明，高产味优基因型与中产味优基因型在水稻分蘖发生与成穗特性上存在明显差异。与中产味优基因型相比，高产味优基因型一次和二次分蘖发生率与成穗率高，单株与群体成穗数多，花后各蘖位光合特性好，促进了库容充实，最终产量较高，南粳5718产量较常农粳10号显著提高7.7%，较多的有效穗数是其产量优势形成的重要基础。与常农粳10号相比，南粳5718拔节期群体穗数较低，但抽穗期和成熟期则较高。南粳5718和常农粳10号分蘖发生与成穗的优势叶位较为一致，一次分蘖中以4/0、5/0和6/0为主，二次分蘖则以1/4和1/5为主。南粳5718单株成穗数、一次和二次分蘖成穗个数显著高于常农粳10号。不同蘖位对单株成穗数和群体产量的贡献率均表现为一次分蘖>主茎>二次分蘖。南粳5718和常农粳10号产量差异主要体现在一次分蘖和二次分蘖上，南粳5718在花后30 d一次分蘖和二次分蘖剑叶的光合速率和叶绿素含量均显著高于常农粳10号。

Tillering Characteristics of High-yielding and High Japonica Rice and Its Relationship with Population Productivity

The high-yield and high-quality japonica rice variety Nangeng 5718 and the middle-yield and high-quality japonica rice variety Changnonggeng 10 were used as the test materials to compare and study the differences in tillering occurrence and panicle formation characteristics of different genotypes, and to clarify the dominant leaf position of the high-yield genotype varieties. The results showed that there were significant differences between the high-yield genotype and the middle-yield genotype in tillering occurrence and panicle formation characteristics. Compared with the middle-yield genotype, the high-yield genotype had higher primary and secondary tillering rates and panicle formation rates, more panicles per plant and group, and better photosynthetic characteristics of each tiller position after flowering, which promoted the enrichment of storage capacity and higher final yield. The yield of Nangeng 5718 was 7.7% higher than that of Changnonggeng 10, more effective panicles were the important basis for its yield advantage. Compared with Changnonggeng 10, the number of panicles of Nangeng 5718 was lower at jointing stage, but higher at heading stage and maturity stage. The occurrence of tiller in Nangeng 5718 and Changnonggeng 10 was more consistent with the dominant leaf position of panicle formation. The primary tiller was mainly 4/0, 5/0 and 6/0, and the secondary tiller is 1/4 and 1/5 was the main one. The number of panicles formed per plant, the number of panicles formed by the primary and secondary tillers in Nangeng 5718 were significantly higher than that of Changnonggeng 10. The contribution rates of different tiller positions to the number of panicles per plant and population yield were all in the following order: primary tiller >main stem>secondary tiller. The yield difference between Nangeng 5718 and Changnonggeng 10 was mainly reflected in the primary tiller and the secondary tiller. Compared with Changnonggeng 10, Nangeng 5718 had higher photosynthetic rate and chlorophyll content in flag leaves 30 days after heading, and the difference was mainly reflected in the first tiller and the second tiller. The photosynthetic rate and chlorophyll content of leaves were in the order of main stem>primary tiller>secondary tiller.