اثر تلقيح قارچ Piriformospora indica و سويه هاي ريزوبيومي بر گياه لوبيا در شرايط تنش شوري و خشكي

چكيده انگليسي :

173Inoculation effect of fungus Piriformospora indica and rhizobium bacteria on common bean under drought and salinity stress Ali Sadeghi Hosni alisadeghee@gmail com Date of Submission January 19 2013 Department of Soil Science College of Agriculture Isfahan University of Technology Isfahan 84156 83111 Iran Degree M Sc Language FarsiSupervisor Dr mozhgan sepehri E mail msepehri@cc iut ac irAbstract Salinity and drought are the most common environmental stresses which have endangered successfulcrops production The vast cultivated areas in Iran are located in arid and semi arid parts of Iran so theseplants are subject to adverse environmental conditions Hence to increase plants tolerance toenvironmental stresses mostly due to water scarcity and exceeding soil salts mineral is important in termsof yield losses Biological methods based on soil useful microorganisms potentials in creating symbiosisrelationship to plants can increase crops yields per unit area by changing their genetic structure improving their cultivation in saline dry soils or biotic and abiotic stresses The present research dealswith effect of simultaneous inoculation of Piriformospora indica and symbiotic rhizobia strains with beanon different growth index under drought and saline stresses during two separate experiments For this alaboratory experiment as factorial in randomized completely design was conducted in soilless researchcenter located in Isfahan university of technology Experimental treatments included two fungi levels inoculation and without inoculation three rhizobia bacteria levels Rb141 Rb 122 and without rhizobia three salinity levels 0 35 and 70 m mol NaCl three drought levels FC 50 FC and 25 FC whichevaluated in thrice replicates The results showed that the highest shoots and roots weight under allexerted salinity levels is belonged to fungi P indica and rhizobia Rb 122 Increased salinity level reducedcontrol aboveground organs potassium potential without fungi and bacteria but in fungi or bacteriainoculated plants there was not significant change in abovementioned element concentration Shoot androot sodium concentration was increased in all studied treatments under increased salinity level so that itwas more appreciable in control plants Root phosphorous concentration inoculated with P indica andalso simultaneously inoculated plants by fungi and bacteria was increased The highest roots P under allsalinity levels was recorded in plants inoculated with Rb 122 fungi and rhizobia As salinity level wasincreased the more activity of Catalase and peroxidase was observed in rhizobia inoculated plants toRb122 and 141 respectively Increased activity of aforementioned enzymes under salinity stress inp indica inoculated plants also was observed but in controls one just catalase activity was increased Unlike all experimental treatments which under salinity stress shoot and root nitrogen were increased thesimultaneous inoculated plants with fungi and bacteria did not show significant change in concentrationof this element Results related to drought stress experiment indicate that increased drought stress reducesshoots dry weight of all studied plants But among plants inoculated by fungi and bacteria the plantsinoculated to fungi P indica showed less reduction of this index than simultaneous inoculated ones Drought reduced potassium concentration of roots in all treatments significantly but those inoculated withfungi had higher potassium in their roots Also implementation of drought stress reduced p concentrationof root and shoot so that inoculated plants to P indica had higher p in their roots Increased drought levellessened nitrogen in shoot and root but comparison of plants inoculated to bacteria and fungi implied tohigher nitrogen concentration in inoculated plants root with Rb122 than those of inoculated to Rb141 It isworthy to note that nitrogen rate of plants roots inoculated by simultaneous fungi and bacteria was muchmore than those inoculated indivi

صادقي حصني، علي

اثر تلقيح قارچ Piriformospora indica و سويه هاي ريزوبيومي بر گياه لوبيا در شرايط تنش شوري و خشكي