水钾耦合对烤烟吸收利用钾素的影响OA

To make reasonable use of water and potassium resources,the Qiandongnan Miao and Dong Autonomous Prefecture of Gui-zhou Province was selected as a study area to explore the effects of different water-potassium coupling modes on the absorption and uti-lization of potassium nutrients in flue-cured tobacco.A field plot experiment was conducted with three irrigation levels(0.50,1.00,and 2.00 L per plant)and three potassium application levels(K2O application rates of 135,270,and 405 kg/hm2).The effects of po-tassium application rate and irrigation amount on the absorption and utilization of potassium nutrients in flue-cured tobacco were inves-tigated.The results showed that the accumulation of potassium in various organs,whole plant and stage of tobacco plants increased with the increase of the potassium application rate and irrigation amount.The absorption of potassium by different organs and its distri-bution proportion among organs followed the order:leaves>stems>roots.The absorption and accumulation intensity of potassium in tobacco plants were different at different growth stages,mainly concentrated in the vigorous growth period,and tobacco leaves were the main absorption and accumulation organs of potassium.The partial productivity of potassium fertilizer decreased with the increase in potassium application rate,while the potassium harvest index was better under medium-high irrigation and potassium application levels.The irrigation water use efficiency decreased with the increase in potassium application rate and irrigation amount.From the per-spective of saving water and fertilizer and potassium absorption by tobacco plants,the coupling treatments of a potassium application rate of 270 kg/hm2 with irrigation amounts of 1.00 L/plant or 2.00 L/plant were more conducive to enhancing the absorption and utiliza-tion of potassium by flue-cured tobacco in the study area.