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181.
182.
Pollutants can have detrimental effects on living organisms. They can cause toxicity, damaging cells, tissues and organs because of their high concentrations or activities. Plants provide a useful system for screening and monitoring environmental pollutants. Among pollutants, aluminum is considered as a primary growth limiting factor for plants resulting in decreased plant growth and development. Although considered to be a non-essential and highly toxic metal ion for growth and development, aluminum (Al) is easily absorbed by plants. Urticaceae family members have high nutrient requirements demonstrated by leaves containing high levels of calcium (Ca), iron (Fe), magnesium (Mg), and nitrogen (N). Urtica pilulifera is one of the important traditional medicinal plants in Turkey. In this study, U. pilulifera was used as a bioindicator to investigate the possible differences in the absorption and accumulation of mineral nutrients at different levels of the Al exposure and examine the mineral nutrition composition of U. pilulifera under Al stress. Also, some growth parameters (leaf-stem fresh and dry weights, root dry weights, stem lengths and leaf surface area) were investigated. U. pilulifera seedlings were grown for two months in growth-room conditions and watered with spiked Hoagland solution, which contained 0, 100, and 200 μM aluminium chloride (AlCl3). It was observed that macro- and micro-nutritional status of roots and leaves was altered by Al exposure. The concentrations of some macro- and micronutrients were reduced while concentrations of others were increased by excess of Al. Some macro- and micronutrients were increased at low level of Al whereas reductions were observed at high level of Al, and vice versa. The patterns were dependent on the macro- or micronutrient and the plant part.  相似文献   
183.
尼日利亚稻田养鱼加灯光诱虫应用效果分析   总被引:1,自引:1,他引:1  
在尼日利亚科基州进行不同沟凼的稻田养鱼加灯光诱虫应用研究,其沟凼模式分围沟和十字沟,灯光以煤油灯代替电灯,鱼稻品种均为当地常见品种。结果表明,开挖占稻田面积10%~15%不同类型的鱼沟或鱼坑,其投入成本相同,鱼稻产量相近,均比单纯稻田收入增加3.5~4.5倍。示范成果还进一步验证了以往在尼日利亚进行的灯光诱虫试验结论,即在稻田养鱼中增加灯光诱虫,能够将有害昆虫变为鱼的全价饲料,减少稻田的病虫害,鱼、稻分别增产14%和9.5%,达到经济效益和生态效益双丰收。  相似文献   
184.
International Aquatic Research - Shrimp is an important traded fishery commodity. When subjected to stress, shrimp usually suffers from oxidative stress, which leads to cell injury, senescence, and...  相似文献   
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