枸溶性钾肥对油菜生长及土壤钾素的影响

Effect of citrate acid-soluble potassium fertilizer application rate on rapeseed growth and soil potassium content

采用盆栽试验方法,研究枸溶性钾肥不同用量对油菜生长及土壤钾素的影响。结果表明：枸溶性钾肥能够明显促进油菜的生长并增加土壤钾素含量。施钾量（K2O）为0.75~3.00g/盆（0.075~0.300g/kg）时油菜生物量与钾素积累量随着施钾量的增加呈先上升后下降的趋势,在施钾量为2.25g/盆时达到最高,分别较对照处理增加70.6%和3.08倍。油菜钾素含量随着施钾量的增加而升高,而钾肥利用率则相反。油菜收获后的土壤速效钾和缓效钾含量随施钾量的增加而增加。枸溶性钾肥的适宜用量为1.50~2.25g/盆。在试验条件下,等量钾养分投入时,枸溶性钾肥处理的油菜生物量、钾素含量、钾素积累量、肥料利用率及土壤钾素含量均略高于水溶性钾肥处理。从钾的养分供应角度考虑,枸溶性钾肥可以替代水溶性钾肥。

The effects of citrate acid-soluble potassium fertilizer on rapeseed growth and soil potas- sium were studied with the pots experiment. The results showed that the citrate acid-soluble potassium fertilizer could promote the growth of rapeseed and increased the content of soil potassium. The biomass and potassium accumulation of rapeseed were increased and then decreased with the increase of applica- tion rate of potassium-silicon mineral fertilizer when the potassium rates was 0. 75-3. 00 g K2 O/pot （0. 075-0. 300 g/kg）. The biomass and potassium accumulation of rapeseed were the highest with potas- sium rates of 2. 25 g/pot. Compared with treatment of no potassium,rapeseed biomass was 70. 6% and the total potassium accumulation increased by 3.08 times. The potassium content of rapeseed was in- creased with the increase of application rate of potassium fertilizer, nevertheless, the nutrient utilization efficiency was opposite. The content of soil available K and slowly available K was increased with the in- crease of application rate of potassium fertilizer. Comprehensive results showed that the optimum citrate acid-soluble potassium fertilizer application was 1.50-2.25 g/pot. Under the condition of this experiment and the same potassium nutrient supply, the biomass, potassium nutrient content, potassium accumula- tion nutrient fertilizer utilization and soil potassium content of citrate acid-soluble potassium fertilizer of rapeseed was higher than water-soluble potassium fertilizer, indicating that citrate acid-soluble potassium fertilizer can replace water-soluble potassium fertilizer from the perspective of potassium nutrient sup- ply.