A Study On New Genotype Strains Of Tobacco In Potassium Nutrition And Its Mechanism

Potassium content in the tobacco leaf direct effect aroma quality and aroma amount of tobacco, direct effect smoldering fire support of tobacco,and in connection with the safety of tobacco products,which is one of the important indicators to measure the quality of tobacco. In this study,by water culture experiment and field experiment, studied of the characteristics of potassium nutrition and mechanism of potassium nutrition differ of different genotypes of flue-cured tobacco. The results are as follows:1.Studying the K nutrition of the four tobacco varieties,the results shows:(1)At seeding stage,the sdw and the total dry weight of GK7 and GK2 are heavy;the K content of various organs and tobacco,and K accumulation in tobacco plants of GK7 and GK2 are high;but the K utilization efficicency of GK7 and GK2 are lower. the sdw, the total dry weight, the K content of various organs and tobacco,and K accumulation in tobacco plants, the K utilization efficicency of all varieties ranged from 1.5277g to 1.9560g, from 1.6720g to 2.1251g, from 65.597mg/g to 74.305 mg/g, from 0.1096g/ plant to 0.1554 g/plant, from 12.278 tol3.93.(2)At large field growth period, the sdw, the total dry weight, the K content of various organs and tobacco,and K accumulation in tobacco plants, the K utilization efficicency of the four tobacco varieties have no sharp distinction,and their utilization efficicency of K fertilizer are different too.Under K condition of soil, the sdw, the total dry weight, the K content of various organs and tobacco,and K accumulation in tobacco plants of are greater than without K condition of soil,but the potassium utilization of the four tobacco varieties are opposite. With the extension of growth period,the K content of tobacco and tobacco leaves are wind down,but the sdw, the total dry weight, K accumulation in tobacco plants and the K utilization efficicency are gradually increased.Among the four tobacco varieties, the sdw and the total dry weight of GK7 and GK2 are heavy;the K content of various organs and tobacco,and K accumulation in tobacco plants of GK7 and GK2 are higher;but the K utilization efficicency of GK7 and GK2 are lower.2. Studying root morphological characteristics and CEC of the four tobacco varieties,the results shows:GK7 and GK2 of higher K absorption capacity had characters such as larger root volume, larger total root area and active area for mineral absorption, larger root surface area, larger root reductive, larger CEC. At large field growth period, root volume, total root area and active area for mineral absorption, root surface area of GK7 and GK2 with the extension of growth period are gradually increased, CEC of GK7 and GK2 first increased then decreased,and vigorous stage top. Under K condition of soil, total root area and active area for mineral absorption, root surface area, CEC are greater than without K condition of soil.3. Studying soluble protein content and ATP activities of the four tobacco varieties,the results shows:GK7 and GK2 of higher K absorption capacity had characters such as larger soluble protein content and ATP activities. At large field growth period,the soluble protein content of GK7 and GK2 with the extension of growth period are gradually increased,but the ATP activities with the extension of growth period are wind down. Under K condition of soil,soluble protein content and ATP activities are greater than without K condition of soil.4. GK7 and GK2 of higher K absorption capacity had dominance in K uptake kinetics.they had larger Vmax and lower Km.