Zhang Xizhong

Preliminary Study on Critical Level of Available Mo in Flue-cured Tobacco Planting Soil

For applying Mo fertilizer in a reasonable and effective way,the effects of molybdenum nutrient on various trait indexes of flue-cured tobacco and critical value of available Mo in soil were studied by field trial and pot experiment.The results showed that tobacco leaf yield was increased and leaf quality was improved by Mo applying.The pot experiment indicated that the critical values of available Mo in soil were 0.30 and 0.10 mg/kg based on yield traits and oil characters of tobacco leaf,respectively.The field trial demonstrated that the critical value of available Mo in soil was 0.15 mg/kg based on yield traits and about 0.02 mg/kg when the proportions of high grade and variegated leaves were concerned.

Effects of Molybdenum on Enzymatic Browning Reaction-related Indexes During Flue-cured Tobacco Curing

The effects of molybdenum application on the AsA content and PPO activity in tobacco leaf during early curing stage and the grade of cured leaf were investigated with field experiments,tobacco of cv.K326,Yunyan85,CB-1 and Honghuadajinyuan(Hongda),was sprayed with molybdenum fertilizer on leaf surfaces.The results showed that for soil deficient of Mo(0.03 mg/kg available molybdenum),the AsA contents in ripe leaves of K326 and Yunyan 85 increased significantly by foliar spray of molybdenum,and the AsA content in tobacco leaves of the 4 cultivars was generally higher than that in CK at early curing stage(0 to 72 h).Foliar spray of molybdenum evidently reduced PPO activity in leaves of K326,Hongda and CB-1,PPO activity in leaves of the 4 cultivars was basically lower than that of CK at early curing stage,especially in 0 to 48 h.Molybdenum application significantly increased the percentage of high and middle grade leaves and decreased the percentage of variegated leaves.