烤烟不同基因型钾营养特性研究

为深入了解烤烟钾营养特性，选择烟叶钾含量具有差异的品种，在正常供钾和无外源钾条件下，研究了烤烟不同基因型对矿物钾活化、吸收、转运和积累的特性。结果表明:在供钾充足条件下，高钾基因型烤烟干物质积累、各部位钾含量和体外钾吸收效率显著高于低钾基因型，根系吸收钾素能力、向叶片中转运钾素能力较强。在无外源钾条件下，高钾基因型烤烟烟叶钾含量和整株钾积累量显著低于低钾基因型，耐低钾能力和根系吸钾能力显著低于低钾基因型。高钾基因型烤烟在缺钾时，会通过增大根系量，提高根冠比，增强对生长介质中矿物钾的活化来提高烟株根际钾含量，但是由于根系吸钾能力较弱，对活化出的钾素未能充分利用。高钾基因型具有对钾素敏感，吸收、转运和积累钾素能力强，钾响应度高，但是不耐低钾的特点，这对于高钾烤烟品种选育和营养施肥具有指导意义。 

Study on potassium nutrient characteristics of flue-cured tobacco of different genotypes

Tobacco (Nicotiana tabacum L.) has a relatively high requirement for potassium(K). In order to study K nutrient characteristics of flue-cured tobacco in depth, characteristics of mineral K activation, absorption, transport and accumulation of different flue-cured tobacco genotypes were studied under normal potassium supply(K+) and non-potassium supply(K-) conditions. Results showed that, the efficiency of K absorption, K responsivity and K content of high K genotypes were higher than those in low K genotypes. Absorbing ability of root, potassium content and dry matter accumulation of high K genotypes were significantly reduced under K-condition. Low K tolerance ability of high K genotypes was lower than that of low K genotypes. High K genotypes would increase activation of mineral K in growth medium to meet their own needs by increasing root volume and root-shoot ratio under K-condition, but the K content of plant was significantly reduced because the lowest K absorption concentration was higher. High K genotypes is sensitive to K, ability of absorption, transport and accumulation of K and the utilization ratio of K fertilizer are high, but low K tolerance ability is low, which has a guiding significance for high K flue-cured tobacco variety breeding and fertilization.