Arbuscular mycorrhizal (AM) fungal extraradical mycelium (ERM) represents the fundamental structure involved in mineral nutrient absorption and translocation from the soil to host plants. With the aim of obtaining in vivo produced ERM, a whole-plant experimental system was devised, characterized by the physical separation of the roots from the substrate and of ERM from the roots. Plant roots were wrapped in a nylon net to obtain a flat mesh pocket, allowing the spreading of ERM from the nylon net onto membranes for its easy collection. Micronutrients content and expression of genes encoding for ammonium transporters (AMT) were analysed in ERM produced by three different AM fungi, Funneliformis mosseae, Rhizoglomus irregulare and Funneliformis coronatus, growing in symbiosis with Cichorium intybus var. foliosum. ERM fresh biomass ranged from 1 to 7 mg per plant, depending on the identity of the symbiont. RT-qPCR analyses of AMT genes showed different expression levels in the ERM of the three fungal isolates. ERM analysis by atomic absorption spectrophotometry and laser induced breakdown spectroscopy (LIBS) showed detectable amounts of micronutrients, such as copper, iron, manganese and zinc. The whole-plant system producing viable and intact ERM represents a useful research tool for morphological, physiological and molecular analyses. Our experimental tool, successfully mimicking mycorrhizal symbioses occurring in natural conditions, is suitable for a virtually limitless range of AM fungi and host plant species.
Physiological and molecular analyses of extraradical mycorrhizal mycelium produced in an in vivo whole-plant system
Cristiana Sbrana;Beatrice Campanella;Daniela Di Baccio;Stefano Legnaioli;Ermenegildo Magnani;Francesco Poggialini;
2017
Abstract
Arbuscular mycorrhizal (AM) fungal extraradical mycelium (ERM) represents the fundamental structure involved in mineral nutrient absorption and translocation from the soil to host plants. With the aim of obtaining in vivo produced ERM, a whole-plant experimental system was devised, characterized by the physical separation of the roots from the substrate and of ERM from the roots. Plant roots were wrapped in a nylon net to obtain a flat mesh pocket, allowing the spreading of ERM from the nylon net onto membranes for its easy collection. Micronutrients content and expression of genes encoding for ammonium transporters (AMT) were analysed in ERM produced by three different AM fungi, Funneliformis mosseae, Rhizoglomus irregulare and Funneliformis coronatus, growing in symbiosis with Cichorium intybus var. foliosum. ERM fresh biomass ranged from 1 to 7 mg per plant, depending on the identity of the symbiont. RT-qPCR analyses of AMT genes showed different expression levels in the ERM of the three fungal isolates. ERM analysis by atomic absorption spectrophotometry and laser induced breakdown spectroscopy (LIBS) showed detectable amounts of micronutrients, such as copper, iron, manganese and zinc. The whole-plant system producing viable and intact ERM represents a useful research tool for morphological, physiological and molecular analyses. Our experimental tool, successfully mimicking mycorrhizal symbioses occurring in natural conditions, is suitable for a virtually limitless range of AM fungi and host plant species.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
