Israel Plant Gene Bank
Agricultural Research Organization ARO
On Wednesday, December 3, 2014, some 5,000 cubic meters of crude oil leaked from the Eilat Ashkelon Pipeline Company’s oil pipeline in the vicinity of Be’er Ora. The oil flowed for about six kilometers from the point of the spill and created sub-channels until it finally reached the Evrona Nature Reserve, causing extensive ecological damage. In addition to this particular oil spill, forty years earlier, in 1975, a similar leak occurred in one section of the oil pipeline located further south of the 2014 spill.
Conventionally, chemical analysis is used to assess the level of contamination and the concentration of components in the soil is tested, although these tests does not provide a complete picture of the potential impact of the pollution. Using biological tests (bioassay) to determine the eco-toxicity of the ground contamination has been widely used in recent years, particularly when the source of pollution, like oil, is a complex mixture of several components.
The Israel Plant GeneBank examined the ability of of wild local species (Acacia raddiana Savi, Rumex cyprius Murb., Malva parviflora L. and Astragalus eremophilus Boiss.) and cultivated crops (Cucumber-Cucumis sativus, Tomato-Solanum lycopersicum, and Pepper- Capsicum annuum) to germinate and the survival capacity of the seedlings and their development in the soil contaminated by the aforementioned oil spills. The seeds, which were collected in the Arava region, were taken from the collection of the GeneBank. Seedlings survival and morphology was strongly affected by the contamination in both old and new spill, and was leading to dwarf plants with few leaves and high mortality rate of the seedlings.
In A. raddiana seeds Three days after planting, seed germination was observed in each experimental and control plot, with germination in the contaminated plots more than three times lower. Twenty-four days after planting in two areas of contamination, mortality of the Acacia raddiana seedlings was observed. With a slow mortality rate in the area of the 1975 spill and a faster mortality rate in the area of the 2014 spill, the survival level of the seedlings was only 4% in the areas polluted by the 2014 spill.
The number of leaves for the Acacia raddiana plants was significantly lower (p <0.001) in plants that germinated in contaminated soil (1975 and 2014) relative to the control plants grown in uncontaminated soil.
The control plants used for the 2014 spill reached a maximum height of 13.5 centimeters on average compared with the average height of 5 centimeters in the contaminated soil (p<0001). The control plants used for the 1975 spill reached a maximum height of 10 centimeters on average compared with an average height of 5.7 centimeters for plants grown in the contaminated soil (p <0.001).