Effects Of Different Fertilization Types On The Development,yield And Quality Of Flue-cured Tobacco

Ji ’an tobacco-producing area is the main tobacco-producing area in Jiangxi Province.The climate in this area is suitable,the soil is fertile,and the organic matter content is rich,which is suitable for tobacco planting.However,the tobacco planting fields are widely scattered,and the soil physical and chemical properties and nutritional conditions of different tobacco planting plots also have certain differences.In addition,flue-cured tobacco production in Ji ’an tobacco-producing area is also faced with soil acidification,lack of magnesium in soil,late ripening of tobacco plants,frequent bacterial wilt and other problems.In this regard,the purpose of this study was to improve and explore a reasonable fertilization program for flue-cured tobacco planting in Jian ’an tobacco-growing area,so as to coordinate flue-cured tobacco nutrition,improve tobacco plant disease resistance,and ensure the steady increase of flue-cured tobacco yield.To balance the chemical composition of tobacco leaves and improve the quality of tobacco leaves,experiments were carried out on the application of magnesium hydroxide,microbial agents and organic fertilizers.The test results are as follows:1.Magnesium hydroxide dosage test:The effects of 300 kg,450kg,600 kg and 750 kg of agricultural magnesium hydroxide on the growth and quality of flue-cured tobacco were investigated before ridging.The results showed that the application of magnesium hydroxide could effectively supplement soil exchange magnesium,increase soil p H value,alleviate soil acidification,and promote the uptake and utilization of soil nutrients such as N,P,K and organic matter by tobacco plants.The application of magnesium hydroxide can promote the growth and agronomic traits of flue-cured tobacco field,especially the growth of leaves,and promote the early growth and rapid development of tobacco seedlings,and advance into the cluster stage.The application of magnesium hydroxide was beneficial to promote the leaf maturity of flue-cured tobacco in late growth period and avoid the late maturation of tobacco plant.Magnesium hydroxide can improve the resistance of flue-cured tobacco and reduce the occurrence of field diseases.Application of magnesium hydroxide can increase the yield of tobacco and the proportion of superior tobacco.The application of magnesium hydroxide can promote the accumulation and transformation of sugar in tobacco leaves,reduce nicotine content,promote the coordination of chemical components in tobacco leaves,and facilitate the accumulation of neutral flavoring components in tobacco leaves.In addition,magnesium hydroxide application can improve the structure,identity and maturity of cured tobacco leaves to a certain extent,but too high magnesium hydroxide application can reduce other appearance quality indicators of tobacco leaves.It is concluded that 750 kg magnesium hydroxide per hectare can be applied to improve soil acidification and supplement soil magnesium nutrition in the flue-cured tobacco production in Ji ’an tobacco-growing area for plots with serious soil acidification and low soil magnesium content.2.Test of magnesium hydroxide after composting with nutrient soil:In order to further explore the best application method and dosage of magnesium hydroxide in the soil climate conditions of jian ’an tobacco-growing area,three dosage levels of magnesium hydroxide were used in the retting of 15 kg,30kg and 45 kg per hectare.The results showed that the application of magnesium hydroxide and nutrient mound retting had little effect on the physical and chemical indexes of tobacco-planting soil,but had some effect on the nutrient supplement and the content of magnesium in soil.The application of magnesium hydroxide in retting with nutrient soil can promote the growth and development of flue-cured tobacco,plant height and effective leaf number,and promote the leaf maturity of flue-cured tobacco.Magnesium hydroxide and nutrient soil composting can reduce the occurrence of disease to some extent.The application of magnesium hydroxide in retting can effectively increase the yield of tobacco leaf,the output value and the proportion of superior tobacco leaf,and it is positively correlated with the dosage of magnesium hydroxide.Magnesium hydroxide and nutrient soil compost can promote the accumulation of nutrients in flue-cured tobacco leaves,especially the accumulation and transformation of sugar,increase the content of chlorine,reduce the content of nicotine and potassium.Magnesium hydroxide and nutrient soil composting had little effect on trace elements in flue-cured tobacco leaves,but it was beneficial to increase the content of neutral flavoring substances in flue-cured tobacco leaves.Magnesium hydroxide and nutrient soil composting had positive effect on the appearance and taste quality of cured tobacco leaves.In the production of flue-cured tobacco,45 kg magnesium hydroxide per hectare and nutrient mound retting can ensure the normal development of flue-cured tobacco,prevent soil acidification and loss of soil magnesium nutrition.3.Microbial agent fertilizer test:Applying 750 kg and 1500 kg microbial agent fertilizer per hectare to study the effects of microbial agent on the growth and quality of flue-cured tobacco in Ji ’an area.The results showed that the microbial agent could improve the field agronomic traits of flue-cured tobacco,promote the elongation of plant height and leaf growth and development at the group and bud stage,and increase the leaf area at the top stage.The microbial agents could increase the SPAD value of flue-cured tobacco leaves and promote photosynthesis.The control effect of microbial agent on bacterial wilt was better,and the occurrence of bacterial disease was negatively correlated with the dosage of microbial agent.The application of microbial agents can promote the absorption and accumulation of nutrients and trace elements in tobacco leaves,especially the accumulation and transformation of sugar,so as to ensure the normal physiological activities of tobacco plants and coordinate the chemical components of tobacco leaves.Microbial agents had little effect on the content of neutral flavoring substances in tobacco leaves.Microbial agents had positive effect on the chroma of middle tobacco leaves after curing,but had little effect on other appearance quality indexes.In order to solve the serious problem of bacterial wilt in The tobacco-producing area of Jian ’an,1500kg/ha is the most suitable microbial agent.4.Type and dosage test of organic fertilizer:The effects of organic fertilizer on the growth,yield and quality of flue-cured tobacco were studied by using different amounts of fermented rapeseed cake fertilizer and Yunnan-Yunye withered cake organic fertilizer.The results showed that the two kinds of organic fertilizer had different effects on the growth and quality of flue-cured tobacco.Self-prepared fermented rapeseed cake fertilizer could better promote the growth and development of flue-cured tobacco from transplanting to budding stage,while Yunnan-Yunye withered cake organic fertilizer had better effect on improving the agronomic traits from budding stage to the end of harvest.The organic fertilizer of Yunnan-Yunye withered cake could promote tobacco leaf ripening,but the effect of selfprepared fermented rapeseed cake fertilizer was not obvious.In terms of economic characters,the yield,output value and medium and upper smoke ratio of self-prepared fermented rapeseed cake fertilizer were better than those of Yunnan-Yunye withered cake organic fertilizer.In terms of chemical composition,the two kinds of organic fertilizers had certain effects on the trace elements in the middle leaves of flue-cured tobacco.The application of organic fertilizers could increase the content of sulfur and reduce the content of copper in the leaves of flue-cured tobacco to a certain extent,but had little effect on the upper leaves.On the aroma components,self-prepared fermented rapeseed cake fertilizer can better promote the accumulation of neutral aroma components.In terms of external quality,both organic fertilizers had certain promoting effect,but the effect of self-prepared fermented rapeseed cake fertilizer was better than Yunnan-Yunye withered cake organic fertilizer.The results showed that 600 kg of self-prepared fermented rapeseed cake fertilizer was the best organic fertilizer for flue-cured tobacco production in ji ’an.