Bazı toprak herbisitlerinin mikorizal fungus Glomus intraradices’in kök kolonizasyonu ve spor sayısı üzerine olan etkileri

Herbicides are the most widely used pesticide groups in the world. It is probable that such heavily used and particularly soil-applied herbicides have highly negative effects on soil microflora. One of the important groups of soil microflora is the mycorrhizal fungi which live symbiotically with plants’ roots and are known to have many benefits to plants. The study was conducted to determine the effects of most widely used soil herbicides trifluralin, linuron, acetochlor and imazethapyr on the root colonization and spore number in the soil of mycorrhizal fungi Glomus intraradices. To this aim, tomato, sunflower, corn and chickpea were inoculated with G. intraradices and grown in potting media under controlled conditions. Related herbicides were applied both in recommended and double doses for each crop plant in the period of pre-plant and pre-emergence. After four weeks incubation periods, the root colonization of mycorrhizal fungi on culture plants and spore number in soil were determined. Root colonization rates of untreated control groups were above 50%, while significant reductions were occurred in application of the recommended and double doses of herbicides. The recommended dose of acetochlor resulted largest reduction in the root colonization by 97% and it was followed by linuron by 87%. In two-fold dose imazethapyr application, mycorrhizal colonization did not occur in chickpeas roots. Again, two-fold dose acetochlor reduced the mycorhizal colonization by 98% in maize roots. It was found that, these herbicides also reduced the spore number of G. intraradices in soil significantly. Among the herbicides used in the experiment, imazethapyr took the first place by reducing the number of spores in soil respectively by 97.2% and 100% with recommended and two-fold doses. Acetochlor followed this herbicide and decreased spore numbers by 81.8% and 89.6%, respectively and thus it took second place. The results indicate that herbicides depending of herbicide group and doses, negatively affect the development and activities of the mycorrhizal fungi living symbiotically with crops. Therefore, it should be noted the selection of herbicides and herbicides which have side effects on non-target organisms must not been preferred