不同钾用量对烟草光合速率和烟株钾含量的影响

研究了不同高效钾用量下,烟草现蕾期光合速率的日变化、生长发育过程中各部位烟叶钾含量的变化,结果表明:对照和K2SO4处理都有"午睡"现象,与K2SO4相比,高效钾肥能更好地改善烤烟光合性能。移栽后60 d前,烟叶钾含量随钾肥施用量的增加而增加,此后,钾肥用量增至一定量后继续增施烟叶钾含量不增反而下降,这种现象先从K2SO4处理中出现,烟叶部位先从中、上部叶开始;烟株根、茎钾含量在移栽30 d时随施钾量的增加而增加,其他测定时期均为先增后降。在整个生育期中,除对照在第60 d、75 d时钾含量表现为根>茎,其他处理在所有测定时期中均表现为茎>根。

Effects of Different Potassium Application Rates on Photosynthetic Rate and Potassium Content of Tobacco Plants

Under the condition of applying different quantities of high-efficient potassium,the daily changes in the photosynthetic rate of tobacco plants at bud stage,and the changes in the potassium content in various parts of tobacco leaves during the growth and development of tobacco were studied.The results showed that both the control(CK) and K2SO4 treatment had a nap phenomenon.The application of high-efficient potassium could better improve the photosynthetic performance of tobacco plants than K2SO4 treatment.Within 60 days after transplanting,the potassium content in tobacco leaf increased with the increase in the application rate of potassium fertilizer.After this,the potassium content in tobacco leaf deceased when the application rate of potassium fertilizer increased to a certain limit,and this phenomenon appeared firstly in K2SO4 treatment and in the middle or upper leaves.On the 30th day after transplanting,the potassium contents in the root and stem of tobacco plants increased with the increase in potassium application rate.While they first increased and then decreased in other testing periods.Throughout the whole growth period(except for the 60th day and 75th day after transplanting in CK),the potassium content in the stem was higher than that in the root in all treatments.