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چكيده انگليسي :

Effect of Endophytic Fungi on Phytorextraction of Zinc in Soil Narges Zamani Aliabadi n zamanialiabadi@ag iut ac ir January 29 2012 Department of agriculture soil science Isfahan University of Technology Isfahan 84156 83111 IranDegree M Sc Language FarsiSupervisor Majid afyuni afyuni@cc iut ac ir Advisors Mohammadreza Sabzalian and Amirhossein KhoshgoftarmaneshAbstractSoil pollution is an important environmental problem which effects human and food health Therefore it hasbeen attracted considerable public attention over the last decades Remediation of contaminated soils inparticular with heavy metals is one of the most important issues Phytoremediation the use of plants and theirassociated microorganisms to remediate a site is an in situ solar powered remediation technology thatrequires minimal site disturbance and maintenance resulting in a low cost and a high public acceptance Mycorrhiza remediation is a new approach for enhancing phytoremediation especially phytoextraction usingfungi and plants symbiosis Neotyphodium endophytes are a group of fungi which stay their entire life cyclewithin the aerial portion of many grass species without any symptoms and increase host tolerance to bioticand abiotic stresses for example increasing plant tolerance to thermal soils soil salinity microbial diseases insect pests improve plant growth and mineral uptake In this study the effects of two genotypes of Festucaarundinacea 75B and 75C clones and seeds and a population of Lolium perenne endophyte infected EI and endophyte free EF by endophytic fungi Neotyphodium sp on zinc tolerance was investigated Theplants were grown in an artificially Zn contaminated soil at 200 400 800 1800 mg Zn kg 1 The grasses weregrown in the soil for 5 months in a greenhouse at Isfahan University of technology At the end of experiment biomass of roots and shoots of grasses photosystem II fluorescence transient the mineral content Zn Mg Mn Ca Cd Cu Fe K Na and P in leafs roots and soil were determined The result demonstrated that endophyte infected festuca contained 34 and 38 more dry roots and tillersnumber than endophyt free festuca respectively Zinc concentration in roots and shoots uptake were 35 and 20 greater in endophyte infected clones compared to endophyte free plants Zinc concentration anduptake in seed and clones of festuca in EI plants were also significantly more than EF plants Dry shootweight and tillers numbers were significantly greater in second cut of lolium compared to first cut Tillersnumber were also greater than in EI lolium but dry shoot weight in EI lolium was 33 less than EF ones Zinc root uptake in EF population was 33 greater than EI grasses but shoot Zn uptake in endophyte infected population were significantly 20 more than endophyte free population Endophyte infectedfestuca esp clones and genotype 75B had higher potential to uptake Zn and accumulate it in root and shootand also higher biomass production Transfer index of Zn in endophyte infected festuca clones was 20 more than EF bioaccumulation factor in EI was also two times higher than EF festuca Our results show thatby populating the rhizosphere with selected microorganisms during the phytoextraction enhanced Zn uptakeof grasses plant biomass and zinc transfer from roots to shoots and from soil to roots By using endophyte infected festuca it is possible to reduce pollution of contaminated soil such as soil around mines Key words Endophyte Phytoextraction zinc

زماني علي آبادي، نرگس

تاثير قارچ هاي اندوفايت بر استخراج گياهي روي از خاك

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