外源硒对胡萝卜生理生化特性、富硒性及其产量的影响

采用不同浓度亚硒酸钠（NasSeO3）进行胡萝卜叶面喷施田间试验，研究硒对胡萝卜硒富集、产量及其生理生化特性的影响．结果表明：叶面施硒可明显提高胡萝卜中各形态硒含量，随施硒量的增加，有机硒转化率随之上升；其全硒、有机硒含量在最大处理浓度（500mg/kg）最高，分别是CK的15．9和26．6倍．施硒除在个别硒浓度提高SOD和CAT活性外，其余浓度酶活降低；施硒低于10mg／kg时有利于胡萝卜叶绿素合成；硒对胡萝卜光和速率则表现负效应．施硒胡萝卜产量较对照降低未达显著水平．综合分析硒对胡萝卜含硒量、产量及其生理生化、以及对人、畜食用的安全性，施硒量以不超过1．0mg／kg为宜．

Effect of selenium on the feature of physiology and biochemistry,Se accumulationand,yield of carrot

The field trials spraying Selenium on the leaves of carrot with 6 treatments of 0(CK),0.5,1.0,50,100 and 500mg kg1 of Se as Na2SeO3studied the effect of Se on Se accumulation, yield and the characteristics physiology of carrot.The results showed that the foliag eapplication of selenium increased significantly the Se content of all formula in carrot.With the increment of application rate of Se,the transformation rate of organic selenium lifted up.Total Se and organic Se reached the peak at the highest concentration treatment of 500mg/kg,which were 15.9 and 26.6 times of that of control respectively.Applying Se with different concentrations on the leaves of carrot decreased the activity of CAT and SOD,except rare Se concentrations.Se increased chlorophyll content of carrot when Se concentrations were 10mg kg-1 below,and Se decreased photosynthetic rate of carrot.In comparison with the control,Se application decreased the carrot yield with no significant.Considering comprehensively the effect of selenium application on the anti-oxidative and physiology,Se accumulation and yield of carrot,as well as food safety for human and livestock health,the appropriate application rate of Se should not be more than 1.0 mg kg-1.