施钾量对烤烟钾吸收利用的影响

目的]研究四川省凉山州主栽烤烟品种云烟85和云烟87对钾的吸收和积累特性,可为当地合理施用钾肥提供理论依据。方法]以云烟85和云烟87为材料进行土培盆栽试验,分析在不同施钾量下烤烟的生物量、含钾量及土壤速效钾和缓效钾含量,探讨施钾量对烤烟钾吸收利用的影响。结果]土壤速效钾和缓效钾的变化量随施钾量的增加而增加,当施钾量超过180 mg/kg时,在土壤供钾能力增强的同时导致大量的钾肥残留于土壤中,增加了经济投入。烟叶的生物量、含钾量和钾分配率在施钾0~180 mg/kg范围内均随施钾量的增加而增加。当施钾量超过180 mg/kg时,烟叶的含钾量增加缓慢,其生物量和钾分配率均降低。随着施钾量的增加,烤烟的钾肥利用率先增加后降低,施钾180 mg/kg时钾肥利用率最高,特别是云烟85的钾肥利用率,在烟叶的3个成熟期分别是施钾90 mg/kg的2.5、4.9和3.2倍。结论]本试验条件下,施钾180 mg/kg能保证烟叶的含钾量,其产量、钾分配率和烤烟的钾肥利用率均较高。这是种植烤烟较理想的施钾量。

Effects of Potassium Absorption and Utilization of Flue-cured Tobacco under Different Potassium Applications

Abstract objective] In order to provide a theoretical basis for rational fertiiization, the potassium abso~rption and accumulation characteristics of flue-cured tobacco Yunyan85 and Yunyan87 in Liangshan Prefecture, Sichuan Province were studied. Method ] Yunyan85 and Yunyan87 were used in the pot culture experiment. In this research, biomass and potassium content of flue-cured tobacco and the content of available potassium and slowly available potassium were analyzed, the effects of potassium absorption and utilization of flue-cured tobacco under different potassium applications were discussed. Result ] The variable quantity of available potassium and slowly available potassium in soil increase when adding po- tassium application. When the potassium application exceed 180 mg/kg, potassium supplying capacity enhanced while many potassium fertilizer residue in the soil. In the context of potassium application 0-180 mg/kg, the biomass, potassium content and potassium distribution rate of to- bacco leaves increase with the increase of potassium application. When the potassium application exceeds 180 mg/kg, the potassium content of to- bacco leaves increase slowly, and their biomass and potassium distribution rate of flue-cured tobacco all decrease. As potassium application im- prove, potassium using efficiency of flue-cured tobacco increase, and then reduce. Maximum appear at 180 mg/kg. Especially, the potassium u- sing efficiency of Yunyan85 at 180 mg/kg is 2.5 times, 4.9 times and 3.2 times at 90 mg/kg during maturity stages. ConclusionJ In this re- search, when the potassium application is 180 mg/kg, it can ensure the potassium content of tobacco leaves, their yield, potassium distribution rate and potassium using efficiency. It is the best potassium application for flue-cured tobacco.