摘要
【目的】探讨叶面施用外源硒对甜樱桃叶片、果实中的硒及有害重金属含量、部分生化指标、果实品质的影响,以期为富硒甜樱桃的生产提供理论依据。【方法】以‘美早’甜樱桃为试材,选取亚硒酸钠(Na2SeO3)溶液为硒源,设置0、5、10、20和40 mg·L-1等5个质量浓度水平,于落花后喷施叶片,1周后再喷施1次。【结果】甜樱桃果实和叶片中的硒含量随施硒浓度的增加而递增,重金属镉和铅的含量均有不同程度的降低。叶面喷硒可显著提高甜樱桃叶片和果实中超氧化物岐化酶(SOD)的酶活性,降低丙二醛(MDA)的活性,减少脯氨酸(Pro)的积累。果实维生素C含量增加、可滴定酸含量降低、果实品质改善。【结论】叶面施硒可以提高甜樱桃果实品质,降低部分重金属的含量。
【Objective】Selenium is one of the essential trace elements in the human body.The deficiency of selenium could be harmful to human health.Although sweet cherries are tasty,beautiful and nutritious,which gets a very popular appeal to people,there is a lack of selenium in sweet cherries.In this experiment,the effects of different selenium concentrations were explored on the main biochemical indexes of leaves and fruits,the fruit quality and heavy metal content,so as to provide a theoretical basis for the production of selenium-rich sweet cherries.【Methods】Sweet cherry‘Tieton’was used as the experimental material,and the sodium selenite(Na2 SeO3)solution was selected as selenium source.The experiment was conducted in Cherry Valley,Houzhai Township,Erqi District,Zhengzhou City,Henan province.The plants were 6 years old with moderate tree vigor at a spacing of 2.5 m×3 m.Sizes of the selected plants as well as the quantity of fruits for every single plant were basically identical.The soil of the experiment area was light sandy soil with pH 7.5.On April 16,after the flower dropping,sodium selenite(Na2 SeO3)solution was sprayed on the surface of the leaves.One week later,the second time spraying was conducted.The concentrations for treatment included 5,10,20 and 40 mg·L-1.All of the spraying was completely randomized with three repetitions.Meanwhile,the control was treated with water.During the fruit ripening period(May 27),appropriate amount of fruits and leaves were taken from the treated plants,which were distributed on the canopy in different directions.Some of them were placed in liquid nitrogen,while the others were brought back in self-sealing bags.The former were stored in an ultra-low temperature refrigerator of-80℃.Measurement included fruit hardness,single fruit weight,contents of titratable acid,soluble solids,vitamin C,selenium,cadmium,lead,mercury,MDA and Pro,as well as SOD activity.【Results】After spraying different concentrations of Na2 SeO3 on the leaves,the selenium in fruits and leaves increased as the increase of selenium concentration.With the concentrations of 5,10,20 and 40 mg·L-1,respectively,selenium contents in leaves were 3.06,7.01,8.61 and 15.06 times than that of the control,reaching a significant level.Furthermore,with the concentrations of 5,10,20 and 40 mg·L-1,selenium contents in fruits were 1.09,5.74,8.76 and 9.36 times higher than that of the control,reaching a significant level.After spraying different concentrations of selenium,the contents of heavy metals in leaves,including cadmium and lead decreased by different degrees.The selenium concentration of 20 mg·L-1 had the best inhibitive effect on cadmium and lead contents in leaves.The selenium concentration of 5 mg·L-1 had the most obvious inhibitive effect on cadmium and lead contents in fruits.In the control,the contents of mercury in leaves and fruits were 0.002 8 mg·kg-1 and 0.000 7 mg·kg-1,respectively.With the selenium treatment,there was no mercury detected in leaves or fruits.After spraying selenium on the leaves,SOD activity in leaves and fruits was higher than that of the control,reaching a significant level.SOD activity in leaves reached the highest level when selenium concentration was 20 mg·L-1,while SOD activity in fruits reached the highest level with selenium concentration of 5 mg·L-1.However,SOD activity in leaves and fruits decreased with the increase of selenium concentration.At the selenium concentrations of 10 mg·L-1 and 20 mg·L-1,the content of MDA in leaves was significant.The content of MDA in fruits reached a significant level when selenium concentration was 5 mg·L-1.However,medium and low selenium concentrations had greater effects on reducing MDA than high selenium concentration.After treatment at different concentrations,the contents of proline in leaves and fruits decreased significantly.After spraying with different concentrations of selenium,the average single fruit weight increased,and the fruit hardness increased by different levels.The average single fruit weight increased most significantly when the selenium concentration was 10 mg·L-1,and the hardness of fruit increased significantly when the selenium concentration was 5 mg·L-1.The AsA content in fruits increased significantly,and titratable acid decreased significantly.At the selenium concentration of 5 mg·L-1,the contents of AsA and titratable acid both reached a significant level.【Conclusion】The selenium sprayed on leaves of sweet cherries can increase the selenium contents in leaves and fruits.The selenium contents in leaves and fruits increased as the selenium concentrations increased.The heavy metal contents in leaves and fruits,including cadmium and lead,decreased significantly,while the content of mercury dropped to an undetected level.In leaves and fruits,SOD activity increased while MDA and Pro contents decreased and lower concentration of selenium had greater effects than higher one.The average single fruit weight and hardness increased.The AsA contents increased at different levels but the titratable acid contents decreased,and the fruit quality was improved.
作者
戚霄晨
简在海
张琦
宋尚伟
QI Xiaochen;JIAN Zaihai;ZHANG Qi;SONG Shangwei(College of Horticulture,Henan Agricultural University/Henan Key Laboratory of Henan Fruit and Cucurbit Biology,Zhengzhou 450002,Henan,China)
出处
《果树学报》
CAS
CSCD
北大核心
2019年第6期748-754,共7页
Journal of Fruit Science
基金
河南省科技厅基础与前沿项目“甜樱桃内参基因的筛选与MADS-Box基因的克隆及表达分析”(152300410074)
河南省果树瓜类生物学重点实验室研究基金
关键词
甜樱桃
硒
叶面喷施
果实品质
重金属
Sweet cherry
Selenium
Spraying
Fruit quality
Heavy metal
