我国南北烟区烤烟产量和营养特性研究

Yield and Nutrition of Flue-Cured Tobacco in Different Tobacco-Growing Regions of China

试验连续3年在我国南北烟区7省10县,选择代表性植烟土壤,采用规范化栽培技术,研究了烤烟生长、氮、磷、钾、钙、镁、硫、氯的营养特性.结果表明,烟株生长和养分吸收速率前期缓慢,中期最快,后期降低.北方烟株后期的生长、氮、磷、钾吸收速率显著高于南方.养分吸收速率的变异系数氮≈钾>磷,中微量元素表现出多样性.在烟株各器官中,营养元素的分配比例叶>茎≥根.叶片养分含量南北差异最大,根系次之,茎南北相似,说明前者易受环境条件的影响,但后者比较稳定,对外界环境不敏感.从总体上看,养分吸收速率、分配比例及叶片含量因养分种类和南北地域不同而异,估计与土壤气候等生态环境有关,这可能是我国烤烟质量风各异的原因之一.值得注意的是,北方烤烟含氯量高而稳定,含氮量北方高于南方,可能导致北方烟叶蛋白质和烟碱含量增加.

A series of field experiments were carried out to investigate growth and nutrition of flue-cured tobacco seedlings grown in typical and representative soils in 10 counties of 7 provinces in north and south China in three consecutive years. The nutrients studied in the experiment included nitrogen, phosphorus, potassium, calcium, magnesium, sulfur and chlorine. The results indicated that growth of and nutrient absorption by tobacco seedlings was slow in the early and late growing periods but fast in the middle growing period and that plant growth and nutrient absorption were greater in north China than in south China in the late growing period. The variation coefficients of nitrogen and potassium absorption were found to be similar but higher than that of phosphorus, while micronutrient absorption varied quite complicatedly in variation coefficients. Nutrients absorbed by the tobacco seedlings were mainly concentrated in leaves and their distribution was in the order of leaf〉stem〉roots. The biggest differences of nutrients between the north and south regions were found in the leaves, less in roots and smallest in stems of tobacco seedlings, indicating the stability of nutrients in stems but sensitivity in leaves to the environment. The rate of nutrient absorption, distribution in organs and concentrations in leaves changed generally with ecosystem envi- ronments including soils and climates. This could be the reasons why the quality of tobacco leaves is so diverse in various tobacco-producing regions of China. What is note-worthy is the fact that chlorine content is stably high in tobacco leaves of north China and nitrogen content is also high, which may lead to high concentrations of protein and nicotine in tobacco leaves.