种植密度对不结球白菜叶面积指数动态变化及产量的影响

以不结球白菜"春油5号"为试材,设置不同种植密度(667m^2种植13 340、16 675、17 787、22 233株),研究了不同种植密度对不结球白菜叶面积指数动态变化及产量的影响,以期为不结球白菜的合理密植提供参考依据。结果表明:在整个生长季节供试的不同种植密度不结球白菜的叶面积指数、单株质量及产量的发展均呈"S"型变化,播种后41d各指标缓慢增加;播种后41～54d各指标呈指数型增长,各种植密度间差异显著;后期到达最高点后保持不变甚至出现下降,处理间差异消失。相关分析表明,种植密度与叶面积指数和产量呈正相关,与单株质量呈负相关,综合不结球白菜单株质量、产量考虑,适宜栽培株行距为20cm×20cm(667m^2种植16 675株),适宜的叶面积指数为3。

Effect of Density on Dynamic Change of Leaf Area Index and Yield of Brassica campestris

In order to provide a theoretical basis for the rational planting density of Brassica campestris,the effects of different planting densities,setting treatments between the density of13 340,16 675,17 787,22 233 plants per 667m^2,on dynamic change of leaf area index and yield of Brassica campestris were studied in this experiment.The results showed that the development trends of leaf area index,single plant weight and yield in different treatments all showed a typical‘S’curve.The growth increased slowly in the early stage,but it increased exponentially during 41 to 51days after sowing and showed a significant difference in various indicators.After reaching the highest point,it basically remained unchanged or even falls and the significant difference between its treatments disappeared.With the increase of planting density,the plant gained in yield and leaf area index,but the weight of individual plant decreased.Considering both single plant weight and yield,the suitable planting line of Brassica chinensis was 20cm×20cm(16 675 plant per 667m^2)and the optimum leaf area index was 3.