【作者】 朱金城；

【导师】 王璞；

【作者基本信息】 中国农业大学 ， 作物栽培学与耕作学， 2013， 博士

【摘要】 华北平原面临严重的水资源危机,而该区域的主要种植制度—一年两熟(冬小麦-夏玉米)的耗水量过大,因而有必要在水资源严重缺乏的区域适当缩减高耗水的冬小麦种植面积,而以两年三熟(冬小麦-夏玉米-玉米)种植制度适度替代一年两熟种植制度,种植制度改变后两年总产量下降幅度较大,主要原因是玉米单产低于产量目标未能弥补减少一季作物的产量损失,因此,本研究着重从玉米季增产角度考虑,在两年产量稳定的基础上大幅度降低种植体系的水分消耗。通过3年田间试验,研究了2个玉米品种在各自适宜密度下调整播期对生育进程、群体结构、源库关系、碳氮代谢及产量形成的影响,以期通过改善气象条件实现玉米高产稳产,以确立可持续发展的高产种植制度。主要研究结果如下：1.玉米总生育期随播期推迟呈缩短趋势,主要缩短时期在播种至8叶展,随着生育期推进,后期各阶段的生长天数差异不大,郑单958与中农大4号的生长天数无明显差距。影响生育进程的最主要因素是平均最高温度(r=0.87),相关极显著；平均气温日较差与生育期天数相关极显著(r=0.70)；平均温度与生育期显著相关(r=0.65)。2.播期推迟玉米株高、穗位高随之增加,茎粗变化不大。冠层透光率随叶面积指数的增加而呈现降低的趋势。随播期推迟吐丝期底层冠层透光率呈现先增加后降低的趋势,穗位层冠层透光率与底层表现类似。3.播期调整对玉米源性能有一定影响。总体而言,最大LAI在2009年随播期推迟先升高后降低,2010及2012年随播期推迟升高。LAD随播期推迟呈现先升高后降低的趋势。从吐丝期至灌浆中期不同层次SPAD值出现穗上层升高而穗下层下降的趋势。群体生长速率(CGR)并未按照播期推迟呈现规律性变化。花前与花后干物重累积量在2009年表现为随播期推迟呈降低趋势,2010年表现为增加趋势,2012年各播期变化不大。播期调整对玉米库性能有一定影响。从穗粒数角度分析,2009>2012>2010年。穗粒数变化在播期间规律变化不一,两品种表现类似。2009年千粒重与2010及2012年相比较高。2009年随播期推迟千粒重呈降低趋势；2010年呈增加趋势；2012年各处理差异不显著。总体而言,随播期推迟粒叶比呈下降趋势。4.随着生育期推进,各器官全氮浓度呈下降趋势,全氮含量表现为叶片及茎鞘呈下降趋势,苞叶+穗轴先升高后降低,籽粒含量呈上升趋势。随生育期推进,总糖浓度表现为叶片先升高后降低,茎鞘呈增加趋势,苞轴呈下降趋势,籽粒呈增加趋势；总糖含量表现为叶片及苞轴先升高后降低,茎鞘及籽粒呈增加趋势。吐丝期随播期推迟各器官C/N呈现降低趋势。成熟期随播期推迟叶片及茎鞘呈现先增加后降低的趋势,以B4最大；苞轴呈现增加的趋势；籽粒呈现持续增加趋势。5.产量表现为2009>2012>2010年。影响产量的最主要构成因素是千粒重,其次是穗粒数。12叶展至吐丝期干物质积累与产量及产量构成因素的关系最密切。有效积温、日照时数及全生育期降水量与两品种产量达到显著正相关；水分利用效率总体表现为2009>2010>2012年。两年三熟种植制度在耗水量上与一年两熟种植制度明显降低。更多还原

【Abstract】 Due to water resources serious shortage in North China plain, the winter wheat and summer maize cropping system consumed too large water and the status quo of unsustainable development. By reducing winter wheat planting area, with winter wheat-summer maize and spring maize cropping system instead of winter wheat and summer maize cropping system. Water consumption reduced but the new problems is grain yield declines. This study focus on grain yield increase in maize season, final realize the grain yield decrease was not significant in three harvests in two years with four harvests in two years, but water consumption significantly reduced.3years field experiment were conducted in Wuqiao experimental station of Hebei province, two maize varieties were used, there are6sowing dates in2009, there are3sowing dates in2010and2012. To research the sowing date change on birth process, population structure, source-sink relationship and yield formation. By improving the ecological conditions achieve stable yield of corn. The main results were as follows:Total growth period showed a trend of shortening with the delayed sowing date. Mainly shorten period in planting to jointing stage. ZD958and ZND4have no obvious difference. The most important factor is Tmax(r=0.87**), followed is daily range of temperature (r=0.70**), followed is mean temperature (r=0.65*).3years experiment results showed that different sowing date has certain influence of agronomic traits in maize plant, with the sowing date delaying the plant height, ear high increased, stem diameter between the interannual have different performance. In general, spring maize and summer maize plant height and ear height have significant difference. Canopy light transmittance increased with the increase of leaf area index shows the tendency of decrease. Bottom light transmittance in2009showed a trend of decrease after the first increase, ear layer of light transmittance and the underlying performance similar to that in2010and2012and2009.Source properties of maize have different performance with delayed sowing date. In general, the leaf area index (LAI) increased first then decreased with delayed sowing date in2009, LAI increased in2010and2012. The group photosynthetic potential firstly increased then decreased with delayed sowing date. From silking stage to mid grouting SPAD values of different levels of head rise upper and lower level decline trend. Population growth rate (CGR) CGR have not obvious rule. Before and after silking dry matter weight have decrease trend along with the sowing date delaying in2009, but it has reverse trend in2010. Sink properties of maize have different performance with delayed sowing date. Kernels per spike performance is2009>2012>2010. It has not significant difference following sowing date change. Thousand kernel weigh has not similar performance. It decreased follow sowing date postpone in2009, but it increased in2010. Kernel/leaf ratio decreased follow sowing date postpone.As the growth period advance, each organ total nitrogen concentration is on the decline, Total nitrogen content of leaf and stem sheath is on the decline, bracts and cob increased first then decreased, total nitrogen content of grain is on the rise. Along with the growth period, the concentration of total sugar of leaf increase first then decrease. Sheaths and grain showed a trend of increase, bracts and cob showed a trend of increase. Total sugar content of leaf and bract-cob increase first then decrease, sheaths and grain showed a trend of increase. Silking stage with the sowing date delaying each organ C/N showed a trend of decrease. Mature period with the sowing date delaying leaf and stem sheath showed a trend of increase first then decrease, bract-cob and grain showed a trend of increase.Grain yield have differences in3years. Thousand kernel weigh is the most important factors to grain yield, followed kernels per spike, harvest ears has less effect on grain yield. From various periods in dry matter weight and yield of correlation analysis showed that the12-leaf period to silking period have the most closely relationship. Effective accumulated temperature, sunshine hours and rainfall in the whole stages was significant positive correlation with grain yield. Water use efficiency (WUE) of overall performance is2009>2010>2012. Water consumption is decreased obviously of three harvests in two years with two harvests in one year.更多还原