叶面喷施锌肥和柠檬酸对辣椒产量、品质与Cd吸收转运的影响

Effect of foliar spraying of zinc fertilizer and citric acid on yield,quality and Cd absorption and transport ation of pepper

为明确ZnSO_(4)与柠檬酸对辣椒的作用效果,以期为辣椒Cd安全生产提供理论依据,采用盆栽试验,研究叶面喷施200μmol·L^(-1)ZnSO_(4)、40μmol·L^(-1)柠檬酸和二者复配对辣椒(Capsicum annuum L.)吸收转运Cd、产量与品质的影响,结果表明:与叶面喷施纯水相比,协同喷施200μmol·L^(-1)ZnSO_(4)与40μmol·L^(-1)柠檬酸(Zn_(200)+CA_(40))处理显著降低了辣椒果实产量、可溶性糖与氨基酸含量,可溶性蛋白含量显著增加,辣椒碱含量变化不显著。供试辣椒品种青红元帅对土壤Cd具有较强的富集能力,不同部位Cd含量为主茎上叶>根>果实>叉茎上叶>叉茎≈主茎;不同处理辣椒果实Cd含量介于0.58~0.79 mg·kg^(-1);与叶面喷施纯水相比,Zn_(200)+CA_(40)处理辣椒果实Cd含量显著(P<0.05)降低了26.58%,该处理显著降低了根净吸Cd量及其主茎上叶与叉茎上叶向果实转运Cd的效率,显著增加了根向主茎、叉茎、主茎上叶与叉茎上叶转运Cd的效率,并显著增加了辣椒地上部营养器官Cd的分配比例,尤其是主茎上叶Cd的分配比例。综上,Zn_(200)+CA_(40)处理果实Cd含量降低主要是由于辣椒根净吸Cd量及其主茎上叶向果实转运Cd的效率降低。

In order to clarify the effects of ZnSO_(4)and citric acid on the pepper and to provide a theoretical basis for the safe production of Cd in pepper,a pot experiment was conducted to investigate effects of foliar spraying of 200μmol·L^(-1)ZnSO_(4),40μmol·L^(-1)citric acid and the combination on the absorption and transportation of Cd in pepper,yield and quality of pepper fruit.The results showed that compared with foliar spraying of pure water,synergistic spraying of 200μmol·L^(-1)ZnSO_(4)and 40μmol·L^(-1)citric acid(Zn_(200)+CA_(40))significantly reduced fruit yield,soluble sugar and amino acid contents,and increased soluble protein content,but had no significant difference in capsaicin.Pod pepper Qing Hong Yuan Shuai had a strong ability to absorb Cd from soil,Cd content in different tissues were as follows:leaf on main stem>root>fruit>leaf on fork stem>fork stem≈main stem.Content of Cd in pod pepper fruit ranged from 0.58 to 0.79 mg·kg^(-1).Compared with foliar spraying of pure water,the Cd content of pepper fruit treated with Zn_(200)+CA_(40)was significantly reduced by 26.58%,and this treatment significantly reduced the net Cd uptake by root and its transfer efficiency of Cd from the leaf on the main stem and the leaf on the fork stem to the fruit,and significantly increased the transfer efficiency of Cd from root to main stem,fork stem,and leaf on the main stem and leaf on the fork stem,and it also significantly increased the distribution ratio of Cd in the aboveground vegetative organs of pepper,especially the distribution ratio of Cd in the leaf on the main stem.In summary,the decrease of Cd content in fruit treated with Zn_(200)+CA_(40)was mainly due to the decrease of net Cd uptake by pepper root and the efficiency of Cd transport from leaf on main stem to fruit.