Study On The Biological Effect Of Flue-cured Tobacoo Under Irrigation And Fertilization Planning

Shortage of water has been a problem which has a strongly inhibitory effect on agriculture sustainable development and entironment improvement,and is also a key point to improve yield and quality of flue-cured tobacco.This thesis has studied the quality and regulation of consumpted water of flue-cured tobacco in different stage,indoor simulation and quantifying irrigation was used,the total consumpted water and fertilizer in field was tested,and the theoretical basis was applied to field experiment in order to determine the proper quality and period of irrigation and the proper amount of fertilizer and the appropriate proportion of supplement,the results were as follows:When abundant water was irrigated to meet the need of tobacco,the water consumption of every tobacco plant during its whole growing stage was 85.42 L.The per cent of water consumption and biomass accumulation was 24.1%,27.5%,31.2% 17.2%and 12.4%,32.6%,34.0%,20.9%in resettling,fast growing,buding and maturity stage,respectively.Accumulation peak of N and K was happened in fast growing stage,but accumulation peak of P was happened in maturity stage.Drought stress happened in resetting stage had no obvious effect on the biomass accumulation of tobacco,but had negative effect on its maturity and tobacco quality. However,when drought stress was happened in fast growing or buding stage,biomass accumulation also received negative influence.So it was important to avoid drought stress during the middle growing stage of tobacco.The results of field plot trials showed that proper control irrigation in resetting stage had negative effect on the agronomic traits of early growing stage,but had positive effect on dry matter accumulation,leaf area,plant height,photosynthetic characteristics of late growing stage.So proper drought treatment in resetting stage of tobacco should be needed to promot the development of root and nutrient assimilation.Fertilization should be different under varied irregation treatment.For example, In drip irrigation condition,the amount of nitrogen with 75 kg/hm~2 and the ratio of basic to supplemental fertilizer of 3:7was much more appropriate to improve the quantity and quality tobacco.