Effects Of Combined Application Of Organic And Inorganic Fertilizers On The Main Soil Fertility Status And Yield And Quality Of Flue-cured Tobacco In Tobacco-rice Rotation System

Flue-cured tobacco is an important economic crop in China,Fujian is one of the three high quality tobacco planting regions of China,which implementing the tobacco-rice rotation cropping system.Long-term and a large number of application of chemical fertilizer in tobacco production brought many negative effects on soil,plants and the environment,combined application of organic and inorganic fertilizers has the vital significance to improve soil,to improve the yield and quality of flue-cured tobacco and to promote sustainable development.At present,there are few studies on effects of combined application of organic and inorganic fertilizers on the main soil fertility status and yield and quality of flue-cured tobacco in tobacco-rice rotation system under long-term experiment.Therefore,the research on effects of combined application of organic and inorganic fertilizers in tobacco-rice rotation conditions was conducted through long-term experiment,to provide the basis for reasonable application of fertilizer in the production process of flue-cured tobacco.The main results were as follows:1.Results of the field experiment indicated that,the main soil fertility status of combined application of organic and inorganic fertilizers was better than that of single application of chemical fertilizer in the second year of the long-term experiment.Compared with the control(T1,single application of chemical fertilizer),the quantity of soil bacteria of combined application of chemical fertilizer and cattle manure(T3)was increased by 1.50×106cfu/g dry soil,the quantity of soil fungi of combined application of chemical fertilizer and biomass carbon(T6)was increased by 5.18×103cfu/g dry soil.Combined application of chemical fertilizer and chicken manure(T4)and combined application of chemical fertilizer and rapeseed meal(T5)increased the activity of soil urease,acid phosphatase and invertase,combined application of chemical fertilizer and pig manure(T2)increased the activity of soil acid phosphatase and catalase.Soil non water stable aggregates of combined application of chemical fertilizer and pig manure(T2),chicken manure(T4),biomass carbon(T6)were increased by 4.69%,9.38%and 7.87%respectively,soil water stable aggregates of combined application of chemical fertilizer and pig manure(T2)and rice straws incorporated into field(T7)were increased by 11.79%and 7.97%respectively,and there was an growing tendency of water stable aggregates of 10-5mm,1-0.5mm and 0.5-0.25mm particle of combined application of organic and inorganic fertilizers.In the second year of the long-term experiment,combined application of chemical fertilizer and pig manure(T2)significantly increased the soil pH value,combined application of organic and inorganic fertilizers increased the soil organic matter content,with that of combined application of chemical fertilizer and pig manure(T2)increased by 13.04%.The soil nitrogen,phosphorus,potassium levels of combined application of organic and inorganic fertilizers were higher in late growth stages of flue-cured tobacco,to meet the nutrient demand of flue-cured tobacco in late growth stages,the soil nitrogen level of combined application of chemical fertilizer and cattle manure(T3)was higher in late growth stages,the soil phosphorus and potassium levels of rice straws incorporated into field(T7)were higher in late growth stages.Combined application of organic and inorganic fertilizers could improve the soil exchangeable calcium and exchangeable magnesium contents,and that of combined application of chemical fertilizer and pig manure(T2)increased by 22.47%and 19.94%respectively.Combined application of chemical fertilizer and pig manure(T2),cattle manure(T3),chicken manure(T4)significantly increased the soil available copper and zinc contents,available copper content increased by 19.43%,10.90%and 9%respectively,available zinc content increased by 13.07%,5.03%and 19.60%respectively.The soil available chromium,arsenic,cadmium,lead contents of combined application of organic and inorganic fertilizers(T2-T7)were decreased by 17.54%-28.25%,39.47%-63.16%,8.02%-22.46%,2.77%-13.05%.In addition,it was found that fertilizations(T1-T9)increased the soil available chromium content,but the soil available heavy metal contents of all treatments did not exceed the standard.2.Results of the field experiment indicated that,combined application of organic and inorganic fertilizers could promote the growth and development of tobacco,and could improve the yield and quality of flue-cured tobacco in the second year of the long-term experiment.Agronomic characters of flue-cured tobacco of combined application of organic and inorganic fertilizers were better 45 and 65 days after transplanting,and overall growth of tobacco of combined application of chemical fertilizer and rapeseed meal(T5)was better.Combined application of organic and inorganic fertilizers could significantly improve the activity of tobacco roots,and could effectively delay the aging of tobacco roots in the late growth period.About the economic characters of flue-cured tobacco,yield of combined application of chemical fertilizer and pig manure(T2)increased by 3.64%,the proportion of high quality tobacco,the proportion of high-medium quality tobacco and the average price of combined application of organic and inorganic fertilizers were increased by 11.13%-16.50%,18.66%-41.00%and 4.57-5.87 yuan/kg,the output value of flue-cured tobacco increased by 367.73-706.63 yuan/mu.Yield and output value of combined application of chemical fertilizer and pig manure(T2)were the highest in different organic fertilizers.In the second year of the long-term experiment,combined application of organic and inorganic fertilizers(T2-T7)effectively reduced the total nicotine and total nitrogen contents of upper leaves,increased the total nicotine content of lower leaves(excepting T2),reduced the total nitrogen content of the lower leaves(excepting T5).It could be concluded from the ratio of sugar to nicotine and the ratio of nitrogen to nicotine that,the coordination of chemical composition of combined application of chemical fertilizer and pig manure(T2)was better overall.About the heavy metals of flue-cured tobacco,Cr mainly accumulated in tobacco roots,As,Cd,Hg,Pb mainly accumulated in tobacco leaves,combined application of organic and inorganic fertilizers(T2-T7)reduced the accumulation of Cr,Cd,Hg in tobacco plant,Cr content of tobacco leaves decreased by 0.76-1.916 mg/kg,Hg content of tobacco leaves decreased by 0.002-0.045mg/kg,combined application of chemical fertilizer and pig manure(T2)significantly decreased the Cd content of tobacco leaves.About the nitrogen,phosphorus and potassium nutrient contents of flue-cured tobacco,combined application of chemical fertilizer and pig manure(T2),chicken manure(T4),rapeseed meal(T5),rice straws incorporated into field(T7)significantly increased the nitrogen content and phosphorus contents of tobacco,phosphorus content of tobacco of combined application of chemical fertilizer and cattle manure(T3)was also increased significantly,combined application of organic and inorganic fertilizers(T2-T7)significantly increased the potassium content of tobacco.3.Results of the field experiment showed that,application of lime to modify soil acid for two consecutive years had a certain impact on the main soil fertility status and tobacco growth.Compared with the control(T1),the quantity of soil fungi of soil acid modified treatment(T8)decreased by 4.49x103cfu/g dry soil,activity of soil urease and catalase were decreased by 4.55%and 24.63%,activity of soil acid phosphatase and invertase were increased by 4.18%and 35.98%,soil non water stable aggregates and soil water stable aggregates were both decreased.The soil pH value was significantly increased,soil organic matter content was decreased by 7.36%,soil alkaline hydrolysis nitrogen,available phosphorus and available potassium contents were decreased,soil calcium content was increased by 26.61%,exchangeable magnesium content was decreased by 1.18%,soil available copper and zinc contents were decreased by 2.01mg/kg and 0.52mg/kg respectively.Soil available chromium,arsenic,cadmium,lead contents were decreased by 26.49%,76.84%,28.86%,18.13%.Influence of soil acid improvement on yield of flue-cured tobacco was not obvious,but the proportion of high quality tobacco,the proportion of high-medium quality tobacco and the average price were increased respectively by 15.60%,36.93%and 6.07 yuan/kg,the output value of flue-cured tobacco was increased by 766.7 yuan/mu.4.Results of the field experiment showed that,the main soil fertility status and tobacco growth changed under the conditions of fertilizer treatment of organic tobacco production.Compared with the control(T1),activity of soil invertase of fertilizer treatment of organic tobacco production(T9)was increased by 47.21%,soil water stable aggregates were increased by 5.03%.The soil pH value was increased by 3.87%,the organic matter content was increased by 0.58%,the alkali hydrolysable nitrogen content was decreased by 1.02%,the effective phosphorus content was decreased by 20.33 mg/kg,the content of available potassium was increased by 0.99%,the soil exchangeable calcium and exchangeable magnesium contents were increased by 5.79%and 6.58%,the soil available copper and zinc contents were decreased by 1.96 mg/kg and 0.48 mg/kg respectively.Soil available chromium,arsenic,cadmium,lead contents were decreased by 22.28%,70.53%,25.50%,13.86%.Yield of Flue-cured tobacco of organic tobacco production treatment was low,but the proportion of high quality tobacco,the proportion of high-medium quality tobacco and the average price were increased by 15.67%,30.86%and 5.8 yuan/kg,the output value was increased by 358.96 yuan/mu.