Effects Of Potash Fertilizer On Yield And Quality Of Tobacco In Fujian Nanping

Flue-cured tobacco is an important leaf economic crop in Fujian province,long-term application of chemical potash fertilizer causes soil acidification and compaction,and environmental pollution.In order to decrease fertilizer and increase effect,and also cultivate high-quality"Wuyi ecological,potassium-rich fragrance" tobacco leaves in Nanping.In the study,field experiments were set in Rendun village,Nanping city.There were 6 potassium treatments with randomized block for 3 duplications.Studied different potassium treatments on tobacco growth and development,quality and quantity as well as soil available nutrients.On the basis of this,soil available potassium absorption and utilization coefficient and utilization efficiency under different potassium treatments were calculated to provide scientific basis for balanced potash fertilizer application and knowing the potassium requirement of tobacco in Nanping.Results showed as below:1.In terms of effects of different potassium levels on economic character of tobacco,the tobacco leaf yield,average price,output value,medium-to-upper ratio of tobacco and economic benefit increased with the increasing of potash fertilizer application amount in the range of potassium(K2O)application rate from 10.52 kg per mu～15.77 kg per mu,which showed a downward trend when potash fertilizer was over 15.77 kg per mu.The output and average price of B treatment reached to 136.06 kg per mu and 21.30 yuan per kilogram,respectively.Though the proportion of finest tobacco was the highest in the E treatment,the ratio of the medium-to-upper tobacco in B treatment was still the highest(94.5%),and the cost of fertilizer increased by a gradient of 29.82 yuan per mu.In total,the best treatment for the economic traits of flue-cured tobacco was B treatment(N:P2O5:K2O 1:0.8:2.1)2.From the point of different potassium levels on tobacco quality,the nitrogen content of tobacco leaves in each treatment was appropriate.Potassium content of tobacco leaves in upper and middle leaves were low.With the increasing content of potash fertilizer,the potassium content in the upper leaves showed a significant upward trend,the content of potassium in the lower leaves was appropriate,resulting in low accumulation of reducing sugar in the middle and upper leaves,but the ratio of sugar to alkali remained in a suitable range,indicating that the potassium fertilizer was slightly insufficient in the late growth stage of tobacco.Therefore,it was beneficial to improve the quality of tobacco leaves after topping when potash fertilizer amount was 15.77 kg/mu.3.In terms of different potassium levels on soil nutrients,available nitrogen content of treatment B and C were significantly higher than other treatments in each growing stages.Microbial biomass nitrogen and microbial nitrogen of treatment B were significantly higher than other treatments in the vigorous stage.Solubilizing potassium bacteria were significant for soil potassium releasing in Nanping tobacco planting area.4.From the point of different potassium levels on potash fertilizer utilization rate,in the range of 10.52～26.27 kg per mu of potassium application.The potash fertilizer utilization rate is between 33.16%and 70.79%,soil available potassium and potassium in plants increased with the increasing proportion of potassium fertilizer.Potassium absorption coefficient of soil available potassium in two growing stages were 0.19 and 0.26,tobacco can absorb 19-26%of potassium in soil directly.The utilization rate of treatment A and B were significantly higher than other treatments,reaching 70.79%and 53.43%.However,proportion of medium-to-upper class tobacco of treatment A was significantly lower than that of treatment B.Therefore,proportion of potash fertilizer of treatment B(potash fertilizer amount 15.77 kg/mu)is more suitable.According to the cost and potassium utilization rate,12.02-15.77 kg per hectare of potash fertilizer is recommended.