Department of Environmental Engineering, Sakarya University, Sakarya, Turkey.
J Agric Food Chem. 2012 Feb 1;60(4):1113-21. doi: 10.1021/jf204150s. Epub 2012 Jan 18.
The grafting of melon plants onto cucurbit rootstocks is a common commercial practice in many parts of the world. However, certain cucurbits have been shown to accumulate large quantities of weathered persistent organic pollutants from the soil, and the potential contamination of grafted produce has not been thoroughly evaluated. Large pot and field experiments were conducted to assess the effect of grafting on accumulation of weathered DDX (the sum of p,p'-DDT, p,p'-DDD, and p,p'-DDE) from soils. Intact squash (Cucurbita maxima × moschata) and watermelon (Citrullus lanatus), their homografts, and compatible heterografts were grown in pots containing soil with weathered DDX at 1480-1760 ng/g soil or under field conditions in soil at 150-300 ng/g DDX. Movement of DDX through the soil-plant system was investigated by determining contaminant levels in the bulk soil and in the xylem sap, roots, stems, leaves, and fruit of the grafted and nongrafted plants. In all plants, the highest DDX concentrations were detected in the roots, followed by decreasing amounts in the stems, leaves, and fruit. Dry weight concentrations of DDX in the roots ranged from 7900 ng/g (intact watermelon) to 30100 ng/g (heterografted watermelon) in the pot study and from 650 ng/g (intact watermelon) to 2430 ng/g (homografted squash) in the field experiment. Grafting watermelon onto squash rootstock significantly increased contaminant uptake into the melon shoot system. In the pot and field studies, the highest stem DDX content was measured in heterografted watermelon at 1220 and 244 ng/g, respectively; these values are 140 and 19 times greater than contaminant concentrations in the intact watermelon, respectively. The xylem sap DDX concentrations of pot-grown plants were greatest in the heterografted watermelon (6.10 μg/L). The DDX contents of the leaves and fruit of watermelon heterografts were 3-12 and 0.53-8.25 ng/g, respectively, indicating that although the heterografted watermelon accumulated greater pollutant levels, the resulting contamination is not likely a food safety concern.
在世界许多地区，将瓜类植物嫁接到葫芦科砧木上是一种常见的商业做法。然而，某些葫芦科植物已经被证明会从土壤中积累大量风化的持久性有机污染物，而嫁接产品的潜在污染尚未得到彻底评估。进行了大型盆栽和田间试验，以评估嫁接对从土壤中积累风化滴滴涕（p,p'-滴滴涕、p,p'-滴滴伊和 p,p'-滴滴滴的总和）的影响。完整的南瓜（Cucurbita maxima × moschata）和西瓜（Citrullus lanatus）、它们的同源嫁接物和相容异源嫁接物在含有风化滴滴涕的土壤中（土壤中滴滴涕为 1480-1760ng/g）或在含有 150-300ng/g 滴滴涕的田间条件下进行盆栽。通过测定嫁接和非嫁接植物的土壤和木质部汁液、根系、茎、叶和果实中的污染物水平来研究滴滴涕在土壤-植物系统中的迁移。在所有植物中，滴滴涕浓度最高的部位是根部，其次是茎、叶和果实中的浓度逐渐降低。盆栽研究中，滴滴涕在根部的干重浓度范围为 7900ng/g（完整西瓜）至 30100ng/g（异源嫁接西瓜），田间试验中为 650ng/g（完整西瓜）至 2430ng/g（同源嫁接南瓜）。将西瓜嫁接到南瓜砧木上会显著增加污染物进入瓜类植物的地上部分。在盆栽和田间研究中，在异源嫁接西瓜中，茎部滴滴涕含量最高，分别为 1220 和 244ng/g，分别是完整西瓜的 140 倍和 19 倍。盆栽植物木质部汁液中的滴滴涕浓度在异源嫁接西瓜中最高（6.10μg/L）。西瓜异源嫁接物的叶片和果实中的滴滴涕含量分别为 3-12ng/g 和 0.53-8.25ng/g，这表明尽管异源嫁接西瓜积累了更多的污染物，但由此产生的污染不太可能成为食品安全问题。
