Preliminary Report on the Effect of Using Humic Acid on Flue-cured Tobacco in Henan

[Objective]The aim was to provide basis for the application of humic acid in flue-cured tobacco in large area.[Method] The influences of fertilizing humic acid at 225 kg/hm2 in the flue-cured tobacco on the yield and quality of tobacco leaf in Henan were studied by the comparative method in multi-site tests.[Result] The plant height and leaf area of flue-cured tobacco in the 2 sites of Linying county and Luoshan county where the humic acid was fertilized were significantly higher than that of CK,and that in the site of Fangcheng county showed some dominance.The plant height and leaf number increased by 2.4～6.0 cm and 0.1～1.3 than CK respctively.Compared with CK,the tobacco yield in 3 sites fertilized humic acid all increased,averagely by 12.7% and the yield value averagely increased 1 666.5 yuan/hm2.Compared with CK,there was no great difference on the average price of flue-cured tobacco,and the proportions of superior and middle tobacco in the sites of Linying county and Fangcheng county were higher than that of CK,that of Luoshan county was lower than that of CK;the total sugar content in tobacco leaf decreased,protein and nicotine contents had some increment,the potassium content in the leaf from middle part was increased,and the ratio of potassium to chlorine was increased.[Conclusion] The humic acid fertilizer can promote the development of tobacco plant,help to yellowing of tobacco leaf,enhance tobacco yield,improve tobacco quality and have the internal substance such as nicotine be more harmonious.