播期、种植密度及追肥对渝青青贮1号的综合影响

Comprehensive effects of sowing date,planting density and topdressing on silage maize Yuqingqingzhu 1

【目的】研究不同播期、种植密度和追肥等因素对青贮玉米生物学性状的影响,为其适宜配套栽培技术措施提供参考。【方法】以青贮玉米品种渝青青贮1号为试验材料,采用L16（43）混合正交试验设计,分播期A1（3月18日）、A2（3月25日）、A3（4月1日）、A4（4月6日）,种植密度B1（株距24.7 cm、67500株/ha）、B2（株距22.2 cm、75000株/ha）、B3（株距20.2 cm、82500株/ha）、B4（株距18.5 cm、90000株/ha）和追肥C1（N 68.25 kg/ha）、C2（N 96.75 kg/ha）、C3（N 125.25 kg/ha）、C4（N 153.75 kg/ha）3因素4水平进行试验,观察记载苗期、抽雄吐丝期、收刈期,株高、茎粗、穗位高、收获期绿叶数、生物产量等指标。【结果】不同种植密度、追肥水平和播期对青贮玉米生物学性状均有不同程度的影响,3因素中种植密度的极差R居首位,是影响青贮玉米生物产量的关键因子,其次是追肥用量和播期。3因素各水平间以3月25日播种、种植密度为75000株/ha、施N量为153.75 kg/ha的生物产量最高（74475 kg/ha）。在栽培技术上采取适时播种（3月25~31日）、合理密植（75000~80000株/ha）、适当增加追肥用量（N 130~150 kg/ha）,能获得最佳的生物产量和理想的株型。【结论】不同种植密度、追肥水平和播期对玉米生物产量均有不同程度的影响,其中种植密度因素对生物产量的影响最大,其次是追肥用量和播期因素。

[Objective]The effects of sowing date ,density and topdressing on biological traits of silage maize were studied to propose appropriate technical cultivation measures for large-scale production. [Method]Taking silage maize Yuqingqingzhu 1 as experimental material, L16（43） mixed orthogonal test was designed. Three faetors and four levels of the experiments were sowing periods： AI （March 18）,A2 （March 25）,A3 （April 1）,A4 （April 6）; densities： BI （24.7 cm spacing, 67500 plants/ha）, B2 （22.2 cm spacing, 75000 plants/ha, B3 （20.2 cm spacing, 82500 plants/ha）, B4 （ 18.5 cm spacing,90000 plants/ha）; topdressings： C1 （68.25 kg/ha of pure nitrogen）,C2 （96.75 kg/ha of pure nitrogen）, C3 （ 125.25 kg/ha of pure nitrogen ）, C4 （ 153.75 kg/ha of pure nitrogen）. Seedling stage, tasseling silking stage, maturity period, plant height, stem diameter, ear height, green leaf number in harvest period, and biological traits were recorded in details. [ Result ] Different densities, fertilizer levels and sowing dates all had different degrees of influence on bio- logical traits of silage maize. Among the three factors, R＇ （density range ）was a key factor affecting silage maize biomass, which was followed by the amount of topdressing and sowing date. The highest yield （74475 kg/ha ） was achieved under the conditions of sowing date of March 25, planting density of 75000 per ha and pure nitrogen amount of 153.75 kg per ha. The best yield and ideal plant type could be obtained by cultivation technology of timely sowing （March 25-31 ）, suitable close planting （75000-80000 plants/ha） and appropriate increase in the amount of fertilizer （pure nitrogen 130-150 kg/ha）. [Conclusion]Different densities,topdressing levels and sowing dates have different effects on biological traits of silage maize. The factor sequence affecting the biological yield is density, topdressing amount and sowing date. Timely sowing, rational close planting and increased dosage of fertilizer are beneficial for im- proving the biological yield of silage maize.