Arbuscular mycorrhizal fungi association promotes corm multiplication in potted saffron (Crocus sativus L.) plants

Arbuscular mycorrhizal fungi (AMF) establish mutualistic symbiotic associations with the roots of living host plants. AMF enhance plant nutrient and water uptake and can act as biofertilizers. There is limited information on AMF association with saffron roots and their effect on agronomic performance. We analyzed the effect of AMF inoculation on potted saffron plants. Two inocula (one with a single fungus Rhizophagus intraradices and one a mix of R. intraradices and Funneliformis mosseae) were applied and compared to a control and a mock inoculation. AMF occurrence was characterized through morphological observations during the vegetative period, together with corm growth, multiplication and wilting. High AMF colonization levels (>71%) and arbuscules production (>58%) were recorded in inoculated plants while little or no colonization occurred in control and mock plants. AMF symbiosis did not influence corm growth (diameter and weight), but increased the production of replacement corms and reduced the occurrence of fungal diseases (ca -72%), compared to control.