PREVENTING CONTAMINATION OF SUPPLY CHAINS BY USING GRAFTED PLANTS UNDER IRRIGATION WITH MARGINAL WATER

摘要

Semiarid and arid regions are characterized by long dry seasons and short wet seasons. To satisfy the demand for food and to combat desertification in these regions, marginal water sources such as saline water and treated domestic sewage (effluent) are increasingly used for irrigation. In effluents, the EC and pH values, and the concentrations of micro-elements, nutrients and dissolved organic matter are, in general, significantly higher than in fresh water. Experiments in a greenhouse and the field were conducted, to compare the responses to irrigation with fresh and effluent water, of non-grafted melon (Cucumis melo L.) cv. Arava plants and melon plants grafted onto the commercial Cucurbita maxima Duchesne x Cucurbita moschata Duchesne rootstock 'TZ-148'. In general the non-grafted plants accumulated much more Na, Ca, Mg and Cl than grafted ones. Moreover the concentrations of microelements like B, Zn, Sr, Mn, Cu, Ti, Cr, Ni, and Cd in the fruits was lower in the grafted plants than in the non-grafted plants. It is suggested that grafting could be a useful tool to prevent entry of contaminants and saline elements into fruits.