干旱胁迫下枸溶性钾肥配施对烤烟土壤理化性质、微生物数量及根系生长的影响

为探明枸溶性钾肥与硫酸钾肥配施对土壤改良和烤烟生长的影响,通过盆栽烟株进行干旱处理,研究枸溶性钾肥不同配施比例在干旱胁迫条件下对土壤理化性质(土壤容重、土壤孔隙度、土壤钾含量),土壤微生物(真菌、细菌、放线菌)活性以及根系生长(根系生物量、根系构型参数、根系活力)的影响。结果表明,施加枸溶性钾肥可使土壤容重降低、孔隙度增大、速效钾和缓效钾含量增加、微生物数量提高,促进烤烟根系生长。在正常水分调控下,以75%枸溶性钾肥+25%的硫酸钾肥的处理最佳;在干旱胁迫条件下,以50%枸溶性钾肥+50%硫酸钾的处理最佳。在烤烟实际生产中,建议在保水能力差的土壤或降雨量少的烟区配施枸溶性钾肥。本研究对改善植烟土壤和提高烟叶品质具有指导意义。

Effects of Citrate Soluble Potassium Fertilizer on Soil Physicochemical Properties of Flue-cured Tobacco,Microbial Quantity and Root Growth Under Drought Stress

In order to investigate the effects of citrate soluble potash and potassium fertilizers on soil improvement and the growth of flue-cured tobacco,potted tobacco was employed to research the influence of citrate soluble potassium fertilizer with different proportions on soil physical and chemical properties (soil bulk density,soil porosity,soil potassium content),soil microbes (fungi,bacteria,and actinomycetes) activity and root growth (root biomass,root configuration parameters,root activity) under drought stress.The results showed that applying citrate soluble potassium fertilizer can reduce soil bulk density,increase soil porosity and the content of available potassium and slowly available potassium,improve microbial quantity,and promote the growth of tobacco roots.Under normal moisture regulation,the treatment of 75％ citrate soluble potassium fertilizer and 25％ potassium sulfate fertilizer was the best.Under drought stress condition,the best treatment was 50％ citrate soluble potassium fertilizer and 50％ potassium sulfate fertilizer.In actual production of flue-cured tobacco,it was recommended that tobacco growing areas of poor water retention or low rainfall should apply citrate soluble potassium fertilizer.This study showed significance for improving tobacco planting soils and promoting the quality of tobacco leaves.