| 摘要: |
| 【目的】研究种植密度和水氮互作对南疆棉花生长、产量和水氮利用效率的影响，为棉田合理密植和水氮优化调控提供技术支撑。【方法】在新疆库尔勒市尉犁县31团进行大田棉花滴灌试验，采用裂区设计，设置种植密度、灌水量和施肥量3个因素，其中种植密度设置2个水平：26万株/hm2(D1，当地种植密度，株距10 cm)和32万株/hm2(D2，株距8 cm);灌水量设置2个水平：80% ETC(W1，ETC为作物蒸发蒸腾量)和100% ETC(W2)；施氮量设置3个水平：200 kg/hm2(N1)、300 kg/hm2(N2)和400 kg/hm2(N3)。在生育期（苗期、蕾期、花期、铃期和吐絮期）测定棉花生长指标，收获时统计产量及产量构成要素。【结果】种植密度和水氮交互对棉花生长、干物质累积、产量和水氮利用效率有显著影响，在高种植密度（D2）下，棉花株高、茎粗、叶面积指数和干物质累积量均随灌水量和施氮量的增加而增加;在低种植密度（D1）下，各指标随施氮量的增加呈先增后减的趋势。吐絮期棉花株高和茎粗均在低密度高水中氮(D1W2N2)处理下达到最大值，分别为105.33 cm和11.16 mm，较D1W2N1、D1W2N3处理分别提高了10.10%，6.40%和6.69%，3.65%；全生育期内各处理棉花叶面积指数（LAI）和干物质增长量均于铃期达到最大值，D1W2N2和D2W2N3处理的最终干物质累积量较大，但二者之间并无显著差异（P<0.05）。籽棉产量、水分利用效率均以D1W2N2处理较大，分别为7 421.0 kg/hm2和1.50 kg/m3。在相同种植密度和灌水量下，氮素利用效率（NUE）、氮素吸收效率（UPE）和氮肥偏生产力（NPFP）均随施氮量增加呈降低趋势，以D2W2N1处理的氮素吸收效率最高，为0.77 kg/kg,较产量最高的D1W2N2处理高4.05%，但其产量较D1W2N2下降约7.0%。【结论】综合高产、节肥和水氮利用效率等因素，种植密度26万株/hm2、生育期灌水100% ETC（311.98 mm）和施氮量300 kg/hm2是南疆棉花膜下滴灌施肥管理的最优栽培方式组合。 |
| 关键词: 棉花栽培 膜下滴灌 水氮耦合 种植密度 水氮利用效率 南疆 |
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| 基金项目:国家重点研发计划项目（2017YFC0403303）；国家自然科学基金项目（51979231） |
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| Effects of planting density and water-nitrogen interaction on cotton growth and water-nitrogen utilization in southern Xinjiang |
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LI Yuepeng,ZHANG Fucang,HOU Xianghao,et al
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| Abstract: |
| 【Objective】This study investigated the effects of planting density and water nitrogen interaction on cotton growth,yield and water and nitrogen use efficiency in southern Xinjiang to provide support for reasonable dense planting and optimal regulation of water and nitrogen in cotton fields.【Method】A field cotton drip irrigation experiment was conducted in the 31st regiment of Yuli,Korla of Xinjiang.Two planting densities of 260 000 plants/hm2(D1,local planting density,plant spacing 10 cm) and 320 000 plants/hm2(D2,plant spacing 8 cm),2 irrigation levels of 80% ETC (W1，ETC is crop evapotranspiration) and 100% ETC (W2),and 3 nitrogen application levels of 200 kg/hm2(N1),300 kg/hm2(N2) and 400 kg/hm2(N3) were set to determine cotton growth indexes during growth as well as yield and yield components at harvest.【Result】Planting density and water nitrogen interaction had significant effects on cotton growth,dry matter accumulation,yield and water-nitrogen use efficiency.Under high planting density (D2),cotton plant height,stem diameter,leaf area index,and dry matter accumulation increased with the increase of irrigation amount and nitrogen application rate.Under low planting density (D1),all indexes showed a trend of first increase followed by decrease with the increase of nitrogen application rate.At harvest,the maximum plant height and stem thickness of 105.33 cm and 11.16 mm were reached in the low density and high water nitrogen (D1W2N2) treatment,which were increased by 10.10% and 6.69% in comparison to D1W2N1 and 6.40% and 3.65% in comparison to D1W2N3.Leaf area index (LAI) and dry matter increase of each treatment during the whole growth period reached the maximum in boll stage.Final dry matter accumulation of D1W2N2 and D2W2N3 treatments was larger without significant difference (P<0.05).Yield and water use efficiency of seed cotton achieved 7 421.0 kg/hm2 and 1.50 kg/m3 in D1W2N2 treatment.Under same planting density and irrigation amount,nitrogen use efficiency (NUE),nitrogen absorption efficiency (UPE) and nitrogen partial productivity (NPFP) all decreased with the increase of nitrogen application rate.The highest nitrogen absorption efficiency of 0.77 kg/kg in D2W2N1 treatment was 4.05% higher,while the yield was about 7.0% lower in comparison with D1W2N2.【Conclusion】Comprehensively considering factors of high yield,fertilizer saving and water nitrogen use efficiency,planting density of 260 000 plants/hm2,100% ETC irrigation during growth period (311.98 mm) and nitrogen application rate of 300 kg/hm2 were the best cultivation methods for drip irrigation and fertilization management of cotton under mulch in southern Xinjiang. |
| Key words: cotton culture drip irrigation under mulch water-nitrogen coupling planting density water and nitrogen use efficiency southern Xinjiang |
