江苏淮北地区不同类型晚播稻茬小麦产量形成特点

半冬性小麦品种淮麦28和淮麦20在较晚的水稻茬口种植时,干物质积累量低,在基本苗270万/hm2时穗数不足,且每穗粒数比适期播种显著减少,产量较低;在基本苗360万/hm2时穗数较多,产量三因素较协调,产量显著提高。而偏春性小麦品种淮麦30和郑麦9023在同样晚播条件下,冬前单株干物质积累量与淮麦28和淮麦20差异不显著,但在270万/hm2基本苗时抽穗～成熟期群体干物质积累量和产量均显著高于淮麦28和淮麦20;在360万/hm2基本苗时抽穗～成熟期群体干物质积累量与产量淮麦30显著高于淮麦28和淮麦20,郑麦9023与淮麦28差异不显著。

Characteristics of Yield Formation of Late - sown Wheat after Rice in Huaibei Area of Jiangsu Province

For semi-winter wheat cultivars Huaimai 28 and Huaimai 20,when their planting density was 2.7 million basic seedlings per hectare,their yields were lower because of low dry matter accumulation,insufficient spikes and significantly lower grains per spike;when their planting density was 3.6 million basic seedlings per hectare,their yields were obviously increased due to more spikes and more harmonious yield components.As for weak-spring wheat cultivars Huaimai 30 and Zhengmai 9023,their dry matter accumulations per plant before overwintering were not significantly different from those of Huaimai 28 and Huaimai 20,but their mass dry matter accumulations from heading to maturity and yields were significantly higher than those of Huaimai 28 and Huaimai 20 under the condition of low planting density(2.7 million basic seedlings per hectare).When the planting density of wheat was 3.6 million basic seedlings per hectare,the mass dry matter accumulation from heading to maturity and yield of Huaimai 30 were significantly higher than those of Huaimai 28 and Huaimai 20,while those of Zhengmai 9023 were not significantly different from those of Huaimai 28.