叶面施硒对甜柿果实品质及重金属含量的影响

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

以‘阳丰’、‘兴津20’和‘次郎’甜柿为试材,分别用0、50、100、150、200mg·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150mg·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0～150mg·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200mg·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’。

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 qualityattributes were assessed. The results indicated that 150 mg·L^-1 Na2SeO3 was considered the optimumconcentration 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^-1Na2SeO3. In the meantime, solublesugar, titratable acid, vitamin C and soluble solids in fruit increased. However, thistrend 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 theeffects 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.