Effects Of Different Biochar Application Amount On Physicochemical Properties Of Tobacco Soil And Tobacco Growth

Biochar is a solid product of biomass under anoxic conditions in whole or in part throughthe formation of a relatively low temperature thermal cracking, with a large specific surfacearea, surface charge and a stronger more stability，into the soil, the physical and chemicalproperties of soil and growing crops will be affected; recently tobacco planting soil nutrientimbalance, decline in soil organic matter, nitrogen ratio imbalance, lead to farmlandecosystem imbalance, so that the quality of tobacco production is poor. For the cultivation oftobacco production problems, combined with the role of biochar soil amendments, and thetest methods pot studied by adding different amounts of biochar to soil after transplantingtobacco seedlings30d (rosette stage),45d (vigorous growing stage),65d (squaring stage),90d（dome stage),110d (mature stage),soil properties, tobacco agronomic traits, a key enzymein the metabolism of carbon and nitrogen, dry weight and influence of the chemicalcomposition of tobacco of each period. The results showed that:During tobacco growth period, the application of biochar treated soil water content werehigher than contrast treatment; soil pH between different treatments had no significantdifferences.During tobacco vigorous growing period,appropriate amount biochar can improvetobacco nitrate reductase activity; adding the right amount of biochar in tobacco vigorousgrowing and squaring stage activity in favor of tobacco to improve; appropriate amount oftobacco in favor of adding biochar in vigorous growing, budding stage and maturity amylaseactivity increased.A suitable amount of application biochar though suppressed initial growth of tobacco, itsignificantly promoted the period after vigorous growth of tobacco, ultimately it improved thetobacco dry weight, significantly improved the coordination of chemical components oftobacco, and improved quality of tobacco. However, excessive application of biocharinhibited the growth of flue-cured tobacco, and reduced quality of tobacco leaves. Thissuggests that a suitable amount of application biochar was good to tobacco growth andimproved coordination of the chemical composition of tobacco.In the present experimental conditions, comprehensive analysis shows that the appropriate biochar application rate should be within the range0.0125~0.025kg/kg soil.