Study On The Application Of Bio-organic Fertilizer In The Cultivation Of Flue-cured Tobacco In Panzhihua

Tobacco is an important Cash crop in our country.In 2019,the area under tobacco leaf cultivation in Sichuan province reached 77,000 hectares,ranking third in the country for the fifth consecutive year.In recent years,unreasonable fertilization methods,excessive use of chemical fertilizers and predatory production have resulted in soil compaction,nutrient imbalance and soil quality degradation in flue-cured tobacco growing areas.In order to find out the optimum application rate of bio-organic fertilizer in tobacco-growing soil and obtain the effect of improving the quality of tobacco leaves,the technical scheme and regulation of flue-cured tobacco planting suitable for different ecological areas in Panzhihua tobacco-growing area were integrated,to provide support for further demonstration and promotion,and finally achieve the goal of reducing chemical fertilizer,improving quality and increasing farmers’income.Based on the traditional flue-cured tobacco planting area in Pingshan Township,Miyi County,Panzhihua,Sichuan Province,five fertilization treatments were set up with different soil fertility and altitude,Including C1:Conventional Fertilization(3450 kg/hm~2 of farm manure+435 kg/hm~2of Compound Fertilizer);C2:full-element bio-organic fertilizer(3450 kg/hm~2);C3:full-element bio-organic fertilizer(3000 kg/hm~2)+compound fertilizer(60 kg/hm~2);C4:full-element bio-organic fertilizer(kg/hm~2)+compound fertilizer(kg/hm~2);C5:Organic Fertilizer(1500kg/hm~2)+compound fertilizer(435 kg/hm~2).By recording the Agronomic and root traits of flue-cured tobacco at the round-growing and mature stages,the effects of bioorganic fertilizer(bio-organic fertilizer)on the above-ground part(including plant height,leaf number,leaf area coefficient,gloss,leaf color,uniformity,growth and disease incidence)and the underground part(including root vigor,root volume,root dry weight,lateral root and adventitious root)of flue-cured tobacco were systematically evaluated,to obtain the optimum application amount of bio-organic fertilizer under different fertility conditions.The main results are as follows:(1)In the newly-cultivated tobacco field,whole-yuan bio-organic fertilizer can significantly increase the plant height,leaf number,leaf area coefficient,luster,leaf color,uniformity and growth tendency of Yunyan 87,and can reduce the incidence rate of Yunyan 87,the number of primary lateral roots and adventitious roots were increased.(2)In the old tobacco field,whole-yuan bio-organic fertilizer could significantly increase the plant height,leaf number,leaf area coefficient,luster,leaf color,uniformity and growth tendency of Yunyan No.87,and reduce the incidence of Yunyan No.87,the number of primary lateral roots and adventitious roots were increased.(3)The application of bio-organic fertilizer at different altitudes could significantly increase the plant height,stem diameter and leaf area of Yunyan 87,decrease the incidence of tobacco disease and increase the root activity.(4)The effects of different fertilization rates on agronomic traits and root traits of Yunyan 87 were significant.All indexes of Yunyan 87 increased and the incidence of disease decreased in both new and old tobacco fields.In this experiment,the optimum application amount of all-round bio-organic fertilizer on tobacco-growing soil with different fertility and altitude was found,which provided the basic data for widening the application range of all-round bio-organic fertilizer and increasing the quality of tobacco leaves.