南方稻区杂交中籼稻高产品种的库源结构及其优化调控规律研究进展

Research progresses and prospects of sink-source structures and optimal regulation of high-yield varieties of hybrid rice in China

  • 摘要: 探明水稻高产品种的库源结构, 对指导育种实践具有普遍意义。在大面积水稻生产中, 利用品种自身的库源特征及种植地的生态和土壤肥力关键指标及其与高产栽培技术的相关性, 确定品种高产优质高效栽培模式, 不仅可节省因种栽培所需的人力、财力, 还可加快新品种示范、推广进程。本文根据已报道资料, 结合笔者20余年的研究结果, 综合分析了杂交水稻高产品种的库源特征及其因种优化调控规律的研究进展。主要内容包括: (1)水稻高产品种的穗粒数以160~220粒为佳, 这类品种在协调了“库”与“源”矛盾的同时, 还较好地利用了基部绿叶的光合生产能力; 大穗型品则应通过适当增施粒肥, 充分发挥下部叶片的光合功能以提高结实率和千粒重。(2)采用扩“库”增“源”的高产栽培策略, 增施氮肥以补充光合源, 从而保证在高粒叶比情况下有较好的籽粒充实度。旱育秧比当地湿润育秧的增产量与海拔高度呈极显著正相关, 与当地湿润育秧的产量水平呈极显著负相关; 水稻高产高效氮肥施用量与地理位置和土壤肥力呈极显著线性关系。氮后移的增产效果与稻田地力呈显著负相关关系, 并通过提高穗粒数和千粒重而增产。建立了以齐穗期剑叶SPAD值(X)预测粒肥高效施用量(Y)的简便适用新方法, Y=30.798X+1 340.9, r=0.954 7**。形成了水稻高产与蓄水相结合的水分管理技术。(3)水稻高产栽插密度分别与施氮量和不同品种之间的穗粒数呈极显著负相关关系; 每穗粒数偏少的品种更适宜强化栽培, 生产上以选择传统栽培条件下的穗粒数不超过170粒的中小穗型品种为宜。前氮后移增产量(Y)与杂交组合穗粒数(X)的关系可表述为: Y=2 607.911.02X (R2=0.630 8), 穗粒数≤237粒可作为采用前氮后移施肥法的杂交品种的选择指标。有待进一步补充和完善的研究内容主要有: 适应机插、机收的杂交水稻品种“库”“源”结构, 杂交水稻前期苗情诊断与高产高效施肥技术, 杂交水稻倒伏的早期监测与预防技术, 和杂交水稻减氮增产高效技术。

     

    Abstract: Exploring sink-source structures of high-yield rice varieties is generally significant for breeding practices. High- yield cultivation mode of large-scale rice production was determined based on sink-source characteristics of high-yield rice varieties, key indicators of ecological conditions, soil fertility of planted areas and high-yield cultivation techniques. As a result, it was not only saved manual labor and financial resources needed for the study of cultivation techniques of new varieties, but also accelerated the processes of demonstration and promotion of new varieties. In view of the reported data and research results of decades (over 20 years) of studies, sink-source structures of hybrid rice for high-yield varieties and the research progress on optimal control were summarized in this paper. The main results included: (1) High-yield rice varieties with 160–220 grains per panicle not only had coordinated contradictions between sinks and sources, but also improved photosynthetic efficiency. For big-panicle rice varieties, special attention was needed for the proper fertilizer application to increase grain filling and full use of the photosynthetic function of lower leaves in order to improve seed setting rate and 1000-grain weight. (2) A high-yield cultivation strategy of hybrid mid-rice with sparse cultivation was adopted with increased nitrogen application and photosynthetic source replenished so as to maintain normal grain filling under high grain-leaf ratio conditions. Increase in grain yield of upland rice seedlings over wet rice seedlings was significantly positively correlated with altitude, while it was significantly negatively correlated with yield of wet rice seedlings. Optimized application of nitrogen in hybrid rice was significantly influenced by ecological site conditions and soil nutrient states. Yield-increasing effects of the postponed nitrogen application and optimized application of nitrogen were strongly negatively correlated with soil fertility. Increase in grain yield was due to increased effective panicle number and 1000-grain weight. Highly significant negative correlations were noted between efficient nitrogen application (Y, kghm-2) for grain filling and SPAD value (X) of the first leaf from top at full panicle stage, Y = 30.798X + 1 340.9 and R2 = 0.911 4. A management technique of high-yield, water-saving rice was developed. (3) Transplanting density had significant negative correlation separately with grains number per panicle and applied N amount for varieties. There was significant effect of intensive cultivation system on yield increase, compared with traditional cultivation. A negative correlation was also noted between increased yield and grains number per panicle among varieties. Hybrid rice with less than 170 grains per panicle in traditional cultivation was suitable for intensive cultivation. Grain yield differences were caused by 2 different fertilization modes: nitrogen fertilizer shifted from basal tillering to panicle initiation (PBSP) stage and heavy basal N plus top-dressing at early tillering stage. Negative correlation was also observed between grain yield increase due to postponed nitrogen application difference (Y) and grains number per panicle (X), i.e., Y = 2 607.9 11.02X (R2 = 0.630 8). Hybrid rice cultivars with grains number per panicle less than 237 were suitable for PBSP fertilization. This research focused mainly on the theory and technique of optimal control of hybrid rice and then pointed out future research directions. The future researches should focuse on sink-source structures of hybrid rice varieties adaptable to mechanical transplanting and harvesting, early diagnosis and optimal fertilization techniques needed for high yields. Also early detection and prevention mechanisms of lodging and cultivation technique of hybrid rice were needed for reduced nitrogen use, increased yield and high-production efficiency.

     

/

返回文章
返回