Effects of Ridge Height and Splitting Application of Potassium on Carbon and Nitrogen Metabolism and Physical and Chemical Properties of Cigar Tobacco Leaves

Wu Yongbing; Chen Yongwei; Yuan Hua'en; He Zhengchuan; Wei Jianjun; Mou Peng; Yang Weili; Zhao Mingqin

doi:10.14083/j.issn.1001-4942.2023.12.018

Abstract：In order to investigate the effects of ridge height and splitting application of potassium on car-bon and nitrogen metabolism during the growth of cigar tobacco and the physicochemical properties of dried to-bacco leaves,a two-factor and three-level field split-zone experiment was conducted using Chuanxue 1 as ma-terial.The ridge heights were set as 35 cm of high ridge(A1),30 cm of medium ridge(A2)and 25 cm of low ridge(A3),and the splitting application treatments of potassium were set as once application of potassium(B1),twice application of potassium(B2),three time application of potassium(B3).Their effects on regula-ting carbon and nitrogen metabolism in cigar tobacco leaves during the growth period were studied,as well as the physical characteristics and chemical composition of tobacco leaves after modulation.The results were as follows.(1)The activities of nitrate reductase,glutamine synthetase,amylase and neutral invertase in leaves increased first and then decreased during the tobacco plant growth period.(2)The activities of key enzymes related to carbon and nitrogen metabolism in leaves could be improved by increasing ridge height and potassi-um application times.With the increase of ridge height,the content of carbon and nitrogen compounds showed an overall increasing trend.At the same height of ridge,the content of carbon and nitrogen compounds of B3 treatment was higher than that of B1 and B2 treatments;the lower ridge could reduce the carbon and nitrogen metabolic intensity in leaves,while three time application of potassium could improve that to a certain extent.The increase of ridge height and potassium application times were conducive to the carbon and nitrogen balance of cigar tobacco leaves at later growth stage.(3)From the viewpoint of physicochemical properties of the to-bacco leaves after modulated,the tobacco leaves treated with A1B3,A1B2 and A2B3 had higher tensile strength,lower starch and protein contents,higher potassium-chlorine ratio,more coordinated chemical com-position of tobacco leaves,and good industrial availability.In conclusion,high ridge and splitting application of potassium could effectively improve the carbon and nitrogen metabolic ability and coordination,promote the inclusions transformation,and improve the intrinsic quality of cigar tobacco leaves.Three time application of potassium with high ridge had the best effect,followed by twice potassium application with high ridge and three time application of potassium with medium height ridge.