Effects of applying nitrogen fertilizer on growth and total alkaloids accumulation in flue-cured tobacco

Effects of applying nitrogen fertilizer on nitrogen uptake and total alkaloids accumulation in flue-cured tobacco were investigated.Results showed that nitrogen amount can be reduced by 20%～30% by regulating nitrogen rates in different periods based either on nitrate diagnosis with uppermost fully expanded leaf or nitrogen absorbing characteristics in different growth stages.No significant difference in tobacco biomass accumulation in various growth periods was observed.However,nitrogen uptake and accumulation in leaves and stems decreased significantly in latter growth period and total alkaloids content and accumulation decreased.As a result,chemical components in flue-cured tobacco leaves were in suitable ranges.It was applicable to regulate total alkaloids and chemical components in flue-cured tobacco leaves.Therefore,tobacco leaf production can be properly managed through optimizing nitrogen fertilizer input based on rapid nitrate testing or nitrogen absorbing characteristics.