Effects Of Biological Carbon Application Rates On Mineral Elements Accumulation And Partial Quality Of Flue-cured Tobacco

Through study the effects of different biological carbon fertilizer on tobacco soil nutrient status,growth and development of flue-cured tobacco,mineral elements,appearance quality and chemical composition of the flue-cured tobacco,to find the best application of biochar to improve the quality of tobacco leaf and promote tobacco production.Experimental design was divided into five treatments:CK:conventional fertilization treatment;T1:no fertilizer treatment;T2:conventional fertilization + biochar 300 kg·hm^-2;T3:conventional fertilization + biochar 600 kg·hm^-2;T4:conventional fertilization + biochar 900 kg·hm^-2.Test results were as follows:1.Application of biochar 600 kg·hm^-2 and 900 kg·hm^-2 in early period promoted the decomposition of soil alkali-hydrolysable nitrogen,available phosphorus and available potassium accumulation and the soil organic matter decomposition,later promoted the absorption of tobacco to soil alkali-hydrolysable nitrogen,available potassium and available potassium.2.The flue-cured tobacco total chlorophyll content of no fertilization decreased gradually,carotenoid content increased gradually;the treatment of biological carbon improved the vigorous gro,wing stage flue-cured tobacco chlorophyll content and reduced the content of carotenoid;in the mature period,the biochar application content in flue-cured tobacco leaves was inversely proportional to the chlorophyll content,and was proportional to the carotenoid pigment content,the chlorophyll content of infrastructure biochar 900 kg·hm^-2 was the lowest,and the carotenoid content was the highest.3.The flue-cured tobacco dry matter accumulation of no fertilization was at least,no fertilizer and applied biochar 300 kg·hm^-2 of treatment reduced the dry matter accumulation,applied biochar 600 kg·hm^-2 and 900 kg·hm^-2 promoted obviously tobacco plant dry matter accumulation,improved the dry matter distribution ratio of the flue-cured tobacco leaves.4.In the mature period of flue-cured tobacco,no fertilizer treatment reduced the percentage of tobacco leaves of Ca,K,Mg,P,N and B;applied biochar 600 kg·hm^-2 and 900 kg·hm^-2 treatment decreased the percentage of flue-cured tobacco leaf Ca,:increased the percentage of tobacco leaves of K,Mg,P,N,B,promoted the absorption of K,Mg,P and N elements in leaves of flue cured tobacco;the treatment of no fertilization and applied biochar decreased the percentage of tobacco leaves of Cu,Mn,increased in the percentage of tobacco leaves of Fe.Among them,the promotion of the absorption of nutrients by the 600 kg·hm^-2 of the biological carbon was the most obvious.5.The score of the flue-cured tobacco leaf structure,identity and oil of no fertilization treatment was the lowest,the treatment of biological carbon improved the maturity of flue-cured tobacco,promoted the structure of the leaf loose,improved the appearance quality of flue-cured tobacco.Among them,the appearance quality of non fertilization treatment was the worst,and the total score of applied biochar 600 kg hm'2 was the highest,which was the most significant to improve the appearance quality of flue-cured tobacco.6.No fertilizer treatment reduced the tobacco total sugar,reducing sugar,nicotine,potassium content;applied biochar 600 kg·hm^-2 and 900 kg·hm^-2 reduced the total sugar content,reducing sugar content and sugar nicotine ratio of upper leaves,increased the total sugar content,reduced sugar content and the ratio of sugar to nicotine in the lower part of the leaf;the treatment of applyied biochar increased nicotine,potassium content and potassium chlorine ratio,reduced chlorine content and the middle leaves nitrogen alkali ratio and improved the lower leaf nitrogen alkali ratio.Among them,applied biochar 600 kg hm'2 made the chemical composition of tobacco leaves in the appropriate range or close to the appropriate range,improved the coordination of the chemical composition of flue-cured tobacco,therefore improved the intrinsic quality of tobacco.In general,the treatment of applied biochar 600 kg·hm^-2 and 900 kg·hm^-2 improved the dry matter accumulation,chlorophyll content,carotenoid content,appearance quality and chemical composition of coordination of flue-cured tobacco,the effect of applied biochar 600 kg·hm^-2 is the best.