窄行匀播对晚播冬小麦群体环境、个体性状和物质生产的影响

为了明确行距和行内种子分布形式对华北平原晚播冬小麦群体生长的影响,以济麦22为试验材料,在晚播条件下设置3种行距(10、15、20 cm)和2种行内种子分布形式[随机分布(R)和均匀分布(A)]处理,考察了不同处理冬小麦的冠层结构与环境特征、个体性状、生物量累积及产量性能。结果表明:在相同播种量下较小行距比较大行距、种子均匀分布比非均匀分布群体叶面积较大,冠层下部漏光较少,温度较低且相对湿度较高;缩小行距或增加行内种子分布均匀度使群体内个体间植株性状差异缩小,穗层分布趋向均匀,花后物质积累量增加,穗粒重增加,最终产量提高。10 cm行距的产量高于15 cm行距、显著高于20 cm行距;在15 cm和20 cm行距下植株均匀分布处理产量显著高于非均匀分布处理的产量。综合研究认为,窄行匀播是华北平原干旱缺水地区提高晚播小麦群体产量的有效措施。

Effects of narrow row spacing and uniform sowing on canopy environment,individual plant traits, and biomass production in late-sowing winter wheat

In order to investigate the effect of row spacing and seed distribution patterns on canopy environment and biomass production of late-sowing winter wheat in the North China Plain, the high-yield cultivar, Jimai 22, was sown in late October 2011-2012 and 2012-2013,with three row spacings (10, 15, and 20 cm) and two seed distribution patterns (random and uniform distribution) within the row. Canopy structure and environment, individual plant traits, biomass accumulation, and yield components were measured. The results showed higher total leaf area and canopy relative humidity, lower canopy temperature, and canopy light leakage in narrow row spacing and uniform seed distribution than in wide row spacing and random seed distribution respectively, under the same sowing rates. With reducing row spacing or improving seed uniformity within the rows, individual plant trait variability decreased, ear distribution uniformity, post-anthesis biomass accumulation, grain weight per ear, and finally grain yield increased. Grain yield in 10-cm row spacing was higher than that in 15-cm row spacing and significantly higher than that in 20-cm row spacing; the yield in uniform seed distribution was significantly higher than that in random seed distribution in 15-cm or 20-cm row spacing. Based on the comprehensive study, it is concluded that combining narrow row spacing and uniform sowing is an effective approach to increase grain yield of late-sowing winter wheat in North China Plain.