膨大期甜瓜果实不同部位5种重金属富集变化的差异性比较

Differential Accumulation Patterns of Five Heavy Metals in Different Parts of the Melon Fruit during the Expansion Phase

摘要:

明确膨大期甜瓜果实不同部位5种重金属富集变化的差异。以7月10日至7月24日采集的甜瓜果实不同部位及果实对应根际土壤为研究对象，根据对应国家标准方法开展了样品中Cd、Cu、As、Ni、Cr 5种重金属的定量分析，并根据定量分析结果，探讨了膨大期甜瓜果实不同部位5种重金属富集系数变化的差异。膨大期内甜瓜果皮Cd、Cu、As富集系数呈降低、升高后降低的变化趋势，Cr富集系数呈先升高后降低的趋势，Ni富集系数呈现出较强的波动性；临近末次采样时间，果肉Cd富集系数整体呈降低趋势（E、F、G部位富集系数分别达0.005 9、0.004 9、0.004 8），Cu、As、Ni、Cr富集系数有升高趋势；A部位和F部位Cd、Cu、Ni、Cr富集变化的差异性相对较高，A部位和E部位As富集变化的差异性相对较强。综上：甜瓜果皮果肉5种重金属的富集变化存在差异，可根据该差异，通过适时延后采摘或提前采收的方式，降低目标调控重金属果实富集水平，为甜瓜果实重金属富集调减技术的研究构建奠定前期基础。

Abstract:

The aim of this research was to clarify the differences in the accumulation patterns of five heavy metals in different parts of the melon fruit during the expansion phase. The research samples were collected from melon fruits and the corresponding rhizosphere soils from July 10 to 24. The contents of five heavy metals, namely, cadmium (Cd), copper (Cu), arsenic (As), nickel (Ni), and chromium (Cr), in the samples were determined using national standard methods. The results suggest that, during the expansion phase, the accumulation coefficients of Cd, Cu, and As in the melon rind first decreased, then increased, and then decreased again. However, the accumulation coefficient of Cr first increased and then decreased, while the Ni accumulation coefficient showed relatively significant fluctuations. Toward the end of the expansion phase, the accumulation coefficient of Cd in the pulp generally showed a decreasing trend (the accumulation coefficients for parts E, F, and G reached 0.005 9, 0.004 9, and 0.004 8, respectively), and the accumulation coefficients of Cu, As, Ni, and Cr increased. The accumulation patterns of Cd, Cu, Ni, and Cr in parts A and F were considerably different, with significant differences are also noted in the accumulation patterns of As in parts A and E. In conclusion, differences were seen in heavy metal accumulation in the melon rind and pulp. Based on these results, the harvest time can be adjusted to reduce the accumulation levels of heavy metals of concern in the fruits. These findings provide a preliminary foundation for future research.