施肥位点调控对植烟土壤及烤烟钾含量的影响

Effects of Fertilization Site Regulation on Potassium Content of Tobacco Planting Soil and Flue-cured Tobacco

烟叶钾含量作为评价烟叶品质的重要指标,如何进一步提升烟叶钾含量是本研究的主要目的。选取四川米易、仁和、河口及内东4个试验区,采用大田微区试验方式,设置4个施肥方式(CK不施钾、T1常规环施、T2底施、T3环施+洞施),研究施肥位点对植烟土壤及烤烟钾含量的影响。结果表明:与常规环施相比,米易、仁和及河口地区,环施+洞施可使烟叶吸钾量提升31%、7%和25%,使烤烟产量提升22%、9%、18%;内东地区,底施可使烟叶吸钾量、烤烟产量分别提升6%、11%。不同的施肥方式决定着钾素在土壤中的分布特征,常规环施使得肥料钾主要分布在烟株根区顶部,而底施则是在较深的部位,只有环施+洞施使得烟株的大部分根系被钾肥所包围,此种施肥方式可有效提升土壤供钾能力,进而促进烟叶钾含量的提升。综合不同施肥方式对植烟土壤及烤烟钾含量的影响得出:环施+洞施施肥方式在米易、仁和、河口地区施肥效果最优,底施施肥方式在内东地区施肥效果最优。

As a crucial index to evaluate the quality of tobacco,how to improve the potassium content of tobacco is the main purpose of this study.4 experimental areas were selected in Miyi,Renhe,Hekou and Neidong of Sichuan Province,and 4 fertilization modes(CK no potassium application,T1 conventional circulating application,T2 bottom application and T3 circulating+hole application)were adopted to study the effect of fertilization sites on the potassium content of tobacco planting soil and flue-cured tobacco.The results show that compared with conventional circulating fertilization,the circulating+hole application increases the leaf potassium uptake by 31%,7%and 25%and the flue-cured tobacco yield by 22%,9%and 18%in Miyi,Renhe and Hekou,respectively.In Neidong,the bottom application increases the leaf potassium uptake and flue-cured tobacco yield by 6%and 11%,respectively.The distribution characteristics of potassium in soil are determined by different fertilization modes.Conventional circulating application distributes potassium fertilizer mainly at the top of the root zone of tobacco,while the bottom application reaches the deeper zone.Only the circulating+hole application could make most of the roots be surrounded by potassium fertilizer,indicating that this fertilization mode could effectively improve the potassium supply capacity of soil and increase potassium content in tobacco.In conclusion,the fertilization effect of circulating+hole application is the optimum in Miyi,Renhe and Hekou,while that of the bottom application is the optimum in Neidong area.