不同施肥位点对烤烟钾积累及土壤有效钾含量的影响

Effects of root zone fertilization on soil effective potassium and potassium absorption of flue cured tobacco

为探明不同施肥位点对植烟土壤有效钾含量和烤烟钾素积累的影响,试验采用大田垄栽的方式,设置T1(对照)、T2(直径15 cm)、T3(直径20 cm)、T4(直径25 cm)4种施肥方法,对成熟期植烟根区不同土层有效钾含量和各个生育期植株根、茎和叶中全钾含量进行测定。试验结果表明,T2、T3和T4处理土壤有效钾含量总体上随着距离植株的宽度的增大而减小,近根区土壤有效钾含量高于远根区,不同施肥位点会改变土壤中有效钾的含量,T4处理土壤有效钾含量低于其它处理。烤烟移栽后第5～9周T4处理根部钾积累量高于其它处理;移栽后第11～15周,T4处理植株钾积累量明显高于其他处理,T4处理钾积累量分别高于对照26.84、21.24和6.88 kg/hm^2;同一施肥处理相同生育期钾素在烟株不同器官中的积累量大小为叶>茎>根。综上,T4处理的施肥位点利于提高烤烟对土壤中钾的吸收和植株钾素的积累。因此,可以考虑在烤烟生产地区采用直径为25 cm,深度20 cm施肥管施肥试行推广。

In order to explore the effect of different fertilization on the content of effective potassium in soil and the accumulation of potassium in flue-cured tobacco,4 kinds of fertilization methods,T1(control),T2(diameter 15 cm),T3(diameter 20 cm)and T4(diameter 25 cm),were used to determine the effective potassium content of different soil layers in the mature tobacco root zone.And the contents of total potassium in roots,stems and leaves of a plant at different growth stages were determined.The results showed that the content of available K in T2,T3 and T4 decreased with the increase of the width of the plant.The content of available K in the soil near the root region was higher than that in the far root zone.The content of effective potassium in soil could be changed by different spatial fertilization,and the content of available K in the treatment of T4 was lower than that of other treatments.After 5~9 weeks of transplanting,the accumulation of potassium in the root of T4 treatment was higher than that of other treatments.After 11~15 weeks after transplanting,the accumulation of potassium in T4 treated plants was significantly higher than that of other treatments.The accumulation of potassium in T4 treatment was higher than that of the control 26.84,21.24 and 6.88 kg/hm^2;The accumulation of potassium in different organs of tobacco plants during the same fertilizer treatment stage was leaf>stem>root.In conclusion,the spatial fertilization by T4 could improve potassium uptake and potassium accumulation in flue-cured tobacco.Therefore,it could be considered that in the area of flue-cured tobacco production,the diameter of 25 cm and the depth of 20 cm fertilization should be popularized.