西南烟区氮素供应与烤烟氮素吸收的关系  

Relationship between nitrogen supply and nitrogen absorption of flue-cured tobacco in southwest China

作　　者：刘青丽[1] 张云贵[1] 焦永鸽[1] 谷海红[1] 夏昊[1] 李志宏[1] 

机构地区：[1]中国农业科学院农业资源与农业区划研究所/烟草行业生态环境与烟叶质量重点实验室,北京100081

出　　处：《植物营养与肥料学报》2017年第3期757-764,共8页Journal of Plant Nutrition and Fertilizers

基　　金：国家烟草专卖局科技项目(110200601014)资助

摘　　要：【目的】氮是影响烤烟产量和品质的最重要元素,本研究旨在探索氮素供应与烤烟氮素吸收的关系,为提升西南烟区烤烟氮素营养管理水平奠定理论基础。【方法】在云南、贵州设置多点施肥试验,采用田间原位培养试验、^(15)N同位素示踪方法,研究烤烟对土壤及肥料氮的吸收。【结果】烤烟氮素累积量与土壤基础供氮量呈线性正相关,土壤基础供氮量分别解释了烤烟氮素累积量和烤烟土壤氮素累积量82.6%和84.8%的变异,是烤烟氮素累积量的决定性因素;土壤基础供氮量与土壤有机质含量密切相关,在土壤有机质含量0~35 g/kg范围内,土壤基础供氮能力随着有机质含量的增加而增加;鉴于烤烟对氮素的需求,土壤基础供氮量在60 kg/hm^2、土壤有机质含量20 g/kg左右较为适宜烟叶品质的形成。烤烟氮素来源主要包括土壤矿化氮、土壤起始无机氮及肥料氮,西南烟区在烤烟大田期土壤氮矿化量为19.9~38.9 mg/kg,大田期土壤矿化氮量与烤烟氮素累积量呈非线性相关,当土壤矿化氮量增加至30 mg/kg以上时,烤烟氮素累积量不再增加;单位土壤有机质大田期矿化氮量与有机质含量的关系可以用对数方程来表达,通过此方程可初步预测土壤矿化氮供应量。西南烟区土壤起始无机氮(0—30 cm)和肥料氮输入量为14.1~237.7 kg/hm^2,两者输入量与烤烟氮素累积量呈显著正相关,当土壤起始无机氮和肥料氮输入量超过150 kg/hm^2时,烤烟氮素的累积量趋于稳定;烤烟氮素累积量随无机氮素供应的增加而增加,烤烟生长季氮供应量超过300 kg/hm^2时烤烟氮素累积量增加趋势变缓,此时烤烟氮素累积量达到了100 kg/hm^2。西南烟区氮肥利用率为25.4%~37.1%,土壤有机质与肥料氮利用率的相关系数达到了0.783(P<0.01),肥料利用率随土壤有机质含量以对数函数方式增长。【结论】在西南烟区烤烟农田生态系统中,烤烟种�[ Objectives ] Nitrogen is the most important element affecting the growth, development and quality of flue cured tobacco. Nitrogen deficiency or excess can greatly affect the yield and quality of flue-cured tobacco. This paper aimed to understand the relation between nitrogen supply and nitrogen uptake of flue-cured tobacco, which can provide a theoretical basis for improving management level of nitrogen nutrition of tobacco grown in southwest China. [ Methods ] Several fertilization experiments were carried out in Yunnan and Guizhou Provinces. The in situ incubation and N isotope tracing method were used to study nitrogen absorption of tobacco from soils and fertilizers. [ Results ] The results showed that the N amount in flue-cured tobacco was positively correlated with the soil basic N supply. Soil basic nitrogen supply （SBNS） explained the variation of nitrogen in flue-cured tobacco and soil nitrogen for 82.6% and 84.8%, respectively, which was decisive factor for nitrogen accumulation in tobacco. SBNS was closely related to the content of soil organic matter. When the soil organic matter contents were within the range of 0-35 g/kg, the SBNS increased with the increase of organic matter content. In view of the requirement of flue cured tobacco to nitrogen, SBNS with 60 kg/hm2 and SOM with 20 g/kg were more suitable for the formation of tobacco leaf quality. The sources of nitrogen in flue- cured tobacco mainly included the mineralized nitrogen, initial inorganic nitrogen in soil and nitrogen fertilizers. The amounts of soil mineralized nitrogen were 19.9-38.9 mg/kg during the growing season. There was a nonlinear correlation between soil mineralized N and N in flue-cured tobacco. The N amount in flue- cured tobacco was not increased when the content of mineralized N increased to 30 mg/kg. The relationship between mineralized N and SOM can be expressed by a logarithmic equation which can predict the supply of mineralized N. The input of soil initial inorganic nitrogen and fertilizer nitrogen was 14.1-237.

关 键 词：起始无机氮 矿化氮 肥料氮 烤烟 

分 类 号：S572[农业科学—烟草工业]