施钾水平对甘肃烤烟钾含量及经济效益的影响

Effects of potassium fertiliser on potassium content in flue-cured tobacco leaves and the economic benefits in Gansu province

针对甘肃烤烟生产中存在的烟叶钾含量低和种植效益不高等问题,于2007年在庆阳市正宁县布置大田试验,在等氮磷用量基础上,研究了施钾水平(0,90,180,270 K2Okg/hm2)对烤烟钾含量及经济效益的影响。结果表明,烟叶钾含量随施钾水平的提高而增加,以施钾量为270 K2Okg/hm2时最高,中部叶片钾含量可达2.11%,接近云南和贵州烟区的烟叶钾含量;不同叶位叶片钾含量对施钾水平的反应不同,以中部叶最为敏感;施用钾肥后,烟株上、中、下部叶片钾含量的高低顺序发生改变。烟叶产量、均价、中上等烟比例和产值等经济效益参数均随施钾水平的提高而持续增加,说明增施钾肥可通过提高产量和改善品质提高烤烟种植的经济效益。在本试验条件下,最佳施钾量可能在270 K2Okg/hm2以上。

Low potassium（K）content in flue-cured tobacco leaves and the low economic benefits of flue-cured tobacco have been a big problem in tobacco production because of inadequate fertilization in Gansu province. The effects of different K rates on K content in flue-cured tobacco leaves and the subsequent economic benefits were studied in a field trial in Zhengning county,Qingyang city,Gansu province in 2007.The four K rates were 0,90,180,and 270K2O kg/ha（treatments K0,K1,K2and K3）.The K content in flue-cured tobacco leaves increased with K fertilization rates and reached a peak at the rate of 270K2O kg/ha.The response of K content in leaves to K application differed with leaf position,and the most sensitive response was in the middle leaves.K fertilizer application had significant effects on the order of K content in upper,middle,and bottom leaves,which changed in K1,K2,and K3treatments compared with K0.The flue-cured tobacco yield,average price,ratio of mid-high grade leaves,output value,and other economic benefit parameters were all increased with increased K fertilizer rate.Therefore increased K fertilizer application could increase economic benefits of flue-cured tobacco by enhancing yield and improving quality.In this field trial,the best K application rate was at least 270K2O kg/ha.