叶面施硒对甜柿果实品质及重金属含量的影响

 以‘阳丰’、‘兴津20’和‘次郎’甜柿为试材，分别用0、50、100、150、200 mg · L^-1 浓 度的亚硒酸钠进行叶面喷施，研究硒和重金属镉、铅、汞在甜柿机体内的积累情况以及硒对果实品质的 影响，探明硒对镉、铅和汞的互作效应，以期为叶面施硒改善甜柿果实品质提供理论依据。试验结果表 明：硒处理浓度以150 mg · L^-1 为最佳；甜柿叶片和果实中的硒含量随施硒浓度的增大而增大；在0 ~ 150 mg · L^-1 范围内随着外源硒浓度的增大，叶片和果实中的镉、铅、汞含量下降，果实中可溶性糖、维生素 C 和可溶性固形物含量上升，可滴定酸含量下降；施硒浓度达到200 mg · L^-1，叶片和果实中重金属含量 上升，果实品质下降；叶面喷硒可明显抑制3 种甜柿品种中镉、铅、汞的含量，并且对‘兴津20’的镉、 汞含量的抑制幅度最大，对‘次郎’中的铅含量抑制幅度最大。‘兴津20’综合表现优于‘次郎’和‘阳 丰’。

Effects of Foliar Feeding of Selenium on Fruit Quality and Accumulation of Cadmium, Lead and Mercury in Sweet Persimmon

This study investigated the potential to improve fruit quality of sweet persimmon （Diospyros kaki）using foliar feeding of selenium. Trees of three cultivars（‘Youhou’，‘Okitsu 20’and ‘Jiro’）were sprayed with Na2SeO3 at five concentrations（0，50，100，150 and 200 mg · L^-1）. Accumulation of heavy metals including cadmium（Cd），lead（Pb）and mercury（Hg）and fruits quality attributes were assessed. The results indicated that 150 mg · L-1 Na2SeO3 was considered the optimum concentration for foliar feeding of Se on sweet persimmon trees. Selenium concentrations in both leaves and fruit increased as application dosage increased from 0 to 150 mg · L^-1 Na₂SeO₃. On the other hand， Cd，Pb and Hg concentrations decreased as application dosage increased up to 150 mg · L^-1 Na₂SeO_³. In the meantime，solublesugar，titratable acid，vitamin C and soluble solids in fruit increased. However，this trend was reversed when application dosage increased further to 200 mg · L^-1 Na₂SeO₃. Of the three cultivars used in this study，treatment effects were more pronounced on‘Okitsu 20’compared with the effects on ‘Youhou’and‘Jiro’. The results indicate that the exogenous application of Se can better the quality of fruit and reduce the content of metal in the persimmon trees.