Effects of the co-inoculation with saprobe and mycorrhizal fungi on Vaccinium corymbosum growth and some soil enzymatic activities

in this study we evaluated the initial plant growth and some biochemical changes produced in rizhosphere soil of blueberry (vaccinium corymbosum l.) cv. 'elliot' plantlets obtained from in vitro culture and inoculated with six arbuscular mycorrhizal (am) fungi strains (gigaspora rosea; glomus claroideum; g. deserticola; g. viscosum; g. intraradices and g. constrictum) and five saprobe fungi (coriolopsis rigida; phanerochaete chrysosporium; trametes versicolor; trichoderma harzianum and penicillium chrysogenum). our results showed a significant "like" am root colonization (25-46%), highlighting the treatment co-inoculated with g. rosea + p chrysosporium or c. rigida; g. intraradices + c. rigida; g. viscosum + p chrysosporium, but this root colonization was morphologically atypical, and dominated by interstitial hyphae, without develop of other typical am structures. furthermore, significant increase in the shoot and root growth of the plantlets inoculated with g. viscosum + p chrysosporium, and g. intraradices + c. rigida were observed. on the other hand, g. claroideum + t. versicolor showed the high increase in the dehydrogenase enzyme activity, while inoculation with g. claroideum alone showed the greatest β-glucosidase activity. these results suggest that the interaction of am symbionts together with saprobe fungi could be a biological alternative to promote the growth of micro-propagated blueberry plantlets in their early growth stages.