In order to study the effects of row spacing on population dynamic changes, leaf area index (LAI),dry matter accumulation ( DMA) and grain yield of Xinmai-26, a compact multi-spike winter wheat cultivar, a two-year field experiment with randomized block design was conducted. The results showed that all the parameters tested had significant difference among the three row spacing treatments, and were consistent between the two growing seasons. The population and LAI increased with the decrease of row spacing. The maximum population,earbearing tiller ratio and maximum LAI were the highest in the treatment of 15 cm. The decline of LAI in treatment 15 cm was the slowest after anthesis. Taking effective accumulated temperature as independent variable, three equations were established by Richards growth curve to simulate the dynamic of DMA,the R2 of which were more than 0. 996. The initial rate,average rate and final amount of DMA in treatment 15 cm were also the highest. Narrowing row spacing could de-crease the grain number per spike,but increase the spike number per hectare,1 000-kernel weight and grain yield. The average yield of treatment 15 cm in two years was 4. 8% and 9. 5% higher than that of treatment 20 cm and 25 cm, respectively. Therefore, the optimum row spacing for compact multi-spike wheat variety Xinmai-26 was 15 cm.%在大田条件下,连续2 a以紧凑多穗型冬小麦品种新麦26为试验材料,采用随机区组设计,研究了3种行距对其群体动态变化、叶面积指数、干物质积累动态和产量的影响。结果表明,行距对上述指标有明显影响,2 a结果一致。随行距变窄,相同时期群体数和叶面积指数呈增加趋势,15 cm行距的最高群体、成穗率和最高叶面积指数均最高,花后叶面积指数下降较缓慢。使用Rich-ards 生长曲线,以有效积温为自变量对冬小麦干物质积累动态进行拟合,R2在0.996以上。干物质积累初始速率、平均速率和最终干物质质量均以15 cm行距最高,并随行距变宽而变小。缩小行距能降低冬小麦的穗粒数,提高成穗数、千粒质量和籽粒产量。15 cm行距2 a产量平均比20 cm和25 cm行距分别高出4.8%和9.5%。紧凑多穗型小麦品种新麦26的最佳行距为15 cm。
展开▼
