玉溪烟区烟叶镁含量分布特征及影响因素

Distribution and Influencing Factors of Magnesium Content in Flue-cured Tobacco Leaves in Yuxi City,Yunnan

为研究玉溪烟区烟叶镁含量的分布状况和影响因素,采集玉溪烟区烟叶和土壤样品,通过描述性统计、方差分析、相关性分析及回归分析的方法,明确了烟叶镁含量的整体分布状况及在不同海拔高度和坡度区间的分布特征,分析了其与土壤全氮、全磷、速效钾、有效镁、有效硼和氯离子之间的关系。结果表明:玉溪烟区烟叶镁平均含量为4.28 g/kg,变幅为0.94~9.17 g/kg,41.2%的烟叶镁含量处于适宜范围(4.0~15 g/kg)。除1700~1900 m海拔区间的烟叶镁含量均值(4.67 g/kg和5.57 g/kg)处于适宜范围外,<1700、1900~2000 m和>2000 m海拔区间的烟叶存在轻度缺镁(2.0~4.0 g/kg)状况。除5°~10°坡度区间的烟叶存在缺镁状况外,<5°和>10°坡度区间的烟叶镁含量(4.55 g/kg和4.34 g/kg)处于适宜范围。烟叶镁含量与土壤全磷和有效镁含量呈极显著线性正相关(P<0.01),与速效钾、有效硼和氯离子含量呈显著线性正相关(P<0.05)。在玉溪烟区需要适当增施磷、钾、镁和硼肥,进一步调控氮肥和氯肥的施用。

In order to study the distribution of Mg content in flue-cured tobacco leaves in Yuxi City,Yunnan,we collected tobacco leaves and soil samples,and clarified the overall distribution of Mg content in flue-cured tobacco leaves,its distribution at different altitudes and slopes and its relationship with soil total N,total P,rapidly available K,available Mg,available B and Cl-by means of descriptive statistics,ANOVA,correlation analysis and regression analysis.The results showed that the average Mg content of flue-cured tobacco leaves was 4.28 g/kg with a variation of 0.94-9.17 g/kg and 41.2%of leaves was in the suitable range(4.0-15 g/kg)of Mg.Except for the 1700-1900 m altitude zone where the mean Mg content of leaves(4.67 g/kg and 5.57 g/kg)was in the suitable range,mild Mg deficiency(2.0-4.0 g/kg)was found in the<1700 m,1900-2000 m and>2000 m altitude zones.Mg content of leaves was in the appropriate range in the<5°and>10°slope zones(4.55 g/kg and 4.34 g/kg)while deficient in the 5°-10°slope zone.Mg content of leaves showed a significant linear correlation with the contents of total soil phosphorus and effective Mg(P<0.01),and a significant linear correlation with the contents of soil rapidly available K,available B and Cl-(P<0.05).In Yuxi tobacco region,appropriate applications of P,K,Mg and B fertilizers are needed to further regulate the application of N and Cl fertilizers.