两个不同适应性冬小麦品种的竞争能力

Competitive Ability of Two Winter Wheat Cultivars with Different Adaptability

采用生态学中的 de Wit替代系列法研究了当前山东省高产广适性冬小麦品种鲁麦 2 1和仅适应局部地区种植的冬小麦品种烟农 15在混播条件下的竞争结局 ,并对其生长特性、资源分配模式及相关性状的差异进行了比较研究。在混播条件下鲁麦 2 1较烟农 15具有明显的竞争优势 ,具有更强的占有和利用共同资源的能力。分蘖数、单位面积穗数、穗粒数、穗粒重、不孕小穗数等对竞争反映敏感 ,而千粒重、每穗小穗数则表现稳定。鲁麦 2 1花后的相对生长率(RGR)和作物生长率 (CGR)在混播时远远大于烟农 15 ,绿色叶面积持续时间长 ,故花后积累的干物质多 ,向穗部分配的物质多 ,有利于提高收获指数和后期抗逆性。竞争能力与适应性之间存在着密切关系 ,而竞争能力强、资源分配合理是冬小麦品种高产广适性协调统一的重要原因。对选育高产和广适性冬小麦品种的设想及相关问题进行了讨论。

Lumai 21 and Yannong 15 are two current winter wheat cultivars in Shandong province with different adaptability. Lumai 21 adapts in the wide area of Shandong province, while Yannong 15 is only suited to specific region. The competitive ability, growth characteristics and dry matter distribution of the two cultivars were investigated via de Wit replacement series. It was shown that Lumai 21 was a superior competitor in mixture, which had higher ability to acquire and utilize the same resources compared with that of Yannong 15. Tiller number, spikes per unit area, kernels per spike, grain weight per spike and sterile spikelets were more sensitive to the competition, while 1000 kernel weight and spikelets per spike was stable in mixture. Since Lumai 21 had a higher relative growth rate (RGR) and crop growth rate (CGR) and longer green leaf area duration after anthesis than Yannong 15 in mixture, it produced and distributed more dry matter to spike, resulted in higher harvest index. The high competitive ability and reasonable partition of dry matter were important factors for integration of high production and adaptability. Some aspects concerned with high-yield and wide-adaptability winter wheat breeding were discussed.