دانلود رایگان مقاله انگلیسی ارزیابی اثرات ژنوتوکسیک خاک تصفیه شده با آفت کش و ورمی کمپوست با آزمون Allium cepa - الزویر 2018

abstract

Soil forms a huge reservoir of nutrients that sustains life on earth. Anthropogenic and natural impacts have led to degradation of land which declines the overall quality of soil, water or vegetation. The present study involves comparison of genotoxicity of soil procured from two different agricultural sites, pesticide treated soil (PTS) and vermicompost treated soil (VTS). The soil was physico-chemically characterized and showed significant differences in terms of cytotoxicity (root length; mitotic index) and genotoxicity (chromosomal aberrations) in Allium cepa test. The mitotic index of the control after 24 and 48 h was found to be 26.1 ± 1.6 and 26.1 ± 1.3 respectively. Mitotic index was reduced to 10.3 ± 0.9 and 9.7 ± 0.6 in 100% PTS and 24.4 ± 1.7 and 25.4 ± 0.8 in 100% VTS after 24 and 48 h of exposure, respectively. Clastogenic aberrations were found to be highest (54.5%) in 100% PTS which was significantly different from VTS extract. The PTS extracts incurred significantly more cytotoxic and genotoxic effects on A. cepa in comparison to VTS. The result indicates that addition of vermicompost in agriculture field acts as soil ameliorator and plays an important role in promotion of cell division and proliferation, hence good for the plant health and crop productivity.

4. Conclusions

A. cepa test is a useful bio indicator of cytotoxicity and genotoxicity and serves as an alert for the population that uses pesticides indiscriminately. The genotoxicity study of soil samples depicts that the use of both inorganic and organic pesticides leads to soil pollution and contamination. Also, the direct use of industrial waste and wastewater, sewage sludge in agricultural land contains much more toxic elements along with useful nutrients. This provides us an insight towards the better understanding of soil contaminants to dodge the potential risks associated with contaminated agricultural soils and affiliated food chains. Pesticides and other pollutants are cytotoxic and have the ability to damage DNA and thus also show genotoxic effects. Vermicompost on the other hand is non-cytotoxic in nature and helps in efficient cell growth. Also, the physico-chemical analysis reveal lower TOC, EC and higher pH and more nutrient content in VTS in comparison to PTS. By the use of vermicompost in lieu of pesticides, the biodiversity and useful organisms do not perish which further tends to elevate the physical and nutritional status of crops. However, the calibration for inorganic fertilizers and plant breeding for agricultural benefits is largely carried out in order to provide maximum yields. Such detailed knowledge and interactions between organic fertilizers and plants still need to be substantiated in order to gain consumer confidence in this organic fertilizer. Further, a clearer concept for vermicompost is required to comprehend its variable and multiplex structure which can exert multifarious effects on soil-functioning. The assessment by A. cepa suggests that in several respects usage of vermicompost is far much better than the pesticides.