Effects Of Different Biomass Charcoals On The Growth And D Development Of Flue-cured Tobacco And Soil

The experiment was carried out in 2016 on the basis of pot and field,four kinds of biochar were used as research materials to set up six treatments respectively: CK1(blank contrast),CK2(conventional fertilization reduced nitrogen 30%),TD(rice husk char+ conventional fertilization reduced nitrogen 30%),TH(peanut shell charcoal +conventional fertilization reduced nitrogen 30%),TM(wheat-straw charcoal+ conventional fertilization reduced nitrogen 30%),TY(tobacco stem charcoal +conventional fertilization reduced nitrogen 30%).1.Physical and chemical properties of different biomass charcoalThe microstructure of the four kinds of biochar is clear,the skeleton is basically intact and the pore structure is rich.There are a lot of micropores in the longitudinal and cross sections of the tobacco stem charcoal,which is more abundant than the other three kinds of biochar in micro Porous structures.The rich microporous structure can enhance the soil water and fertilizer retention performance,help the soil to release nutrients slowly,provide a large number of breeding and living places for the microorganism,increase the soil porosity and improve the soil respiration rate.Compared with the two kinds of shell biochar,the rice husk char is 4.54 times of peanut shell charcoal,Compared with two kinds of rhabditiform biochar,the wheat straw charcoal was 5.62 times of that of the tobacco straw charcoal,While the peanut shell charcoal is 2.48 times the tobacco stem charcoal.The specific surface area of rice husk char was the largest,and the absorption capacity and water retention capacity were the strongest.The contents of total nitrogen and total carbon in tobacco stem charcoal were 2.415% and 56.990%,respectively,followed by wheat straw charcoal,peanut shell charcoal.Followed by wheat straw carbon,peanut shell carbon,those in rice husk carbon were the lowest,which were 0.665% and 26.780%,respectively.The carbon content of tobacco stem charcoal and wheat straw charcoal was high,which provided a lot of carbon for soil,promoted the growth and improved the quality of tobacco leaves.There were significant differences in the absorption peak of rice husk charcoal at 800-1200 cm-1 band with others.The results showed that the functional groups of rice husk charcoal were more abundant,and its adsorption capacity and exchange capacity were stronger than those of other three kinds of biochar.2.Effects of different biomass charcoal on soil physical and chemical propertiesThe addition of four kinds of biochar in the early stage of tobacco growth,the alkaline nitrogen in soil release slowly,release rapidly in the later period.Among them,the slow release effect of TY was obvious,which was related to the microporous structure of tobacco straw charcoal.Variation of available phosphorus content of each treatment was not obvious.The content of available potassium in the soil of TM and TY was higher than that of CK2 in the whole growth period,which may be related to the type of biochar.The results showed that wheat straw char and tobacco strem charcoal significantly increased the content of available potassium,and promoted the absorption of potassium,which is of great significance to improve the quality of tobacco leaves.The organic carbon content of TY in the whole growth period was higher than that of CK2,which indicated that the soil organic carbon content was increased by tobacco strem charcoal,and the effects of other treatments on soil organic carbon content were inconsistent.TH and TM had the best effect on reducing soil bulk density,which may be related to the rich microporous structure of peanut shell and wheat straw carbon,which reduce the weight of the soil in the unit volume.3.Effects of different biomass charcoal on tobacco growth and development The effect of TH on plant height and stem girth was the most significant,and TY has a significant effect on improving leaf area.The root activity of TH was highest in the vigorous growing period,In the late growth stage of CK1.This may be related to stress factors,This may be related to stress factors,tobacco plants of CK1 could not grow normally due to lack of nutrients,the growth period was extended,for better absorb nutrients,the root activity must be maintained.The root volume increased rapidly in the early stage of TH,and the latter increased slowly,and the root volume of TD,TY and TM was larger than others at 90 days.The aboveground biomass was TY,TH and TD were the second,and TM was more than CK2.The differences between TD,TH,TM and TY may be related to the physical and chemical properties of biochar.The micropore structure,functional groups and specific surface area of biochar have different effects on the physical and chemical properties of soil,while the growth of tobacco root system is closely related to the physical and chemical properties of soil.In summary,the effect of tobacco strem charcoal and peanut shell charcoal on the growth of tobacco plant was better than that of rice husk char and wheat straw charcoal.The content of total nitrogen was high in the long term.At 90 days,except for CK1,the total nitrogen content of other treatments decreased.Illustration that except CK1,other treatment of tobacco began to mature,and TD,TY were better promote than others.The potassium content in tobacco leaves was decreased in the early stage.On the 75 day,the potassium content in some treatments increased slightly.The content of potassium in tobacco leaves was consistent with the content of available K in soil.TM and TY had the highest amount of potassium in tobacco leaves,which was related to the type of biochar.However,the influence of the shell like carbon and stalk biochar on soil potassium content needs to be further explored.The effects of four kinds of biochar on reducing sugar and total sugar in tobacco leaves were significantly decreased.TM had the lowest content of reducing sugar and total sugar,which showed that biochar could reduce the total sugar content of tobacco leaves.4.Effects of different biomass charcoal on quality of flue cured tobacco leavesThe contents of reducing sugar and total sugar were higher in the middle and upper leaves.The total sugar content in tobacco leaves of TH and TD was higher than that of other treatments.TM treatment had the most significant effect on nicotine content in the middle and upper leaves,followed by TH.TD and TH had a significant effect on the increase of total nitrogen content in central tobacco leaves,while TM and TH increased the content of total nitrogen in upper leaves.TH and TD had the best effect on reducing chlorine content in middle and upper leaves,but TM and TY increased the content of chlorine in middle and upper leaves.TY and TM promoted the increase of potassium content in tobacco leaves,which better than TH and TD.TM and TD promoted the increase of two sugar ratio in central leaves.Biochar reduced the ratio of two sugar to the upper leaves,and TY decreased the maximum,the smallest reduction was TM.Application of four kinds of biochar decreased in middle leaf nitrogen alkali ratio,TD and TM reduced minimum.The ratio of nitrogen to alkali in the upper leaves was in the appropriate range,but the effect of TH was the best,TD followed.The middle leaves of flue-cured tobacco neutral aroma constituents,neoplytadiene,except neoplytadiene substances other neutral aroma,phenylalanine,browning reaction products,cembranoids,carotenoids degradation types are CK1,TD,TY treatment was the highest.In the tobacco growing areas,the priority of the selection of tobacco stem charcoal in the improvement of organic carbon in the soil,in the reduction of soil bulk density,improve the nicotine content can be given priority to the selection of peanut shell charcoal,wheat straw charcoal as a modified material.Wheat straw charcoal and tobacco stem charcoal can be used as the first choice to improve the potassium content in Flue-cured tobacco.In the improvement of neutral aroma substances in the central leaves,rice husk charcoal and tobacco strem charcoal can be given priority.