Effects of arsenic on development and yield and quality of flue-cured tobacco

A systematic experiment was conducted by pot experiments to determine the effects of arsenic toxicity on development,yield and quality of flue-cured tobacco.The results showed that arsenic toxicity inhibited development of flue-cured tobacco.It delayed the growing process,and decreased leaves,leaf area,plant height,and yield.Besides,it decreased economic properties,such as output value per plant,average price,and ratio of high level,and chemical quality properties such as increase in total sugar,reduce sugar,total nitrogen,and nicotine.It also decreased content of potassium,calcium,magnesium and chlorine.Therefore,it resulted in disproportion of sugar-nitrogen,nitrogennicotine,sugar-nicotine and potassium-chlorine.And hence,arsenic induced decrease both in economic value and in chemical value.The results also showed that when flue-cured tobacco was planted in soil added to 100 mg/kg of arsenic,it was so affected that there was no production value.When soil was added more than 200 mg/kg of arsenic;flue-cured tobacco could not grow.When soil was added 16.89 mg/kg of arsenic;yield was decreased by 10%.Arsenic content in leaves increased with arsenic addition in soil.Accumulation of arsenic in leaves of flue-cured tobacco was first from lower leaves,to cutters,and then to upper leaves.After cutters were burned at 300 temperatures,residues of arsenic in ash were 39.58%,the remaining(60.42%) were inbreathed by smokers or entered into the air.The arsenic residues in lower leaves,cutters,upper leaves and smoke of cutters was less than 5 mg/kg specified in food hygienic standard,when the critical content of arsenic applied in soil was 2.63,6.56,13.91 and 12.90 mg/kg,respectively.