title: Cyanobacterial extracts containing microcystins affect the growth, nodulation process and nitrogen uptake of faba bean (Vicia faba L., Fabaceae).
abstract: The use of irrigation water containing cyanobacterial toxins may generate a negative impact in both yield and quality of agricultural crops causing significant economic losses. We evaluated the effects of microcystins (MC) on the growth, nodulation process and nitrogen uptake of a Faba bean cultivar (Vicia faba L., Fabaceae), particularly the effect of MC on rhizobia-V. faba symbiosis. Three rhizobial strains (RhOF4, RhOF6 and RhOF21), isolated from nodules of local V. faba were tested. The exposure of rhizobia to MC showed that the toxins had a negative effect on the rhizobial growth especially at the highest concentrations of 50 and 100 μg/l. The germination of faba bean seeds was also affected by cyanotoxins. We registered germination rates of 75 and 68.75% at the toxin levels of 50 and 100 μg/l as compared to the control (100%). The obtained results also showed there was a negative effect of MC on plants shoot, root (dry weight) and total number of nodules per plant. Cyanotoxins exposure induced a significant effect on nitrogen assimilation by faba bean seedlings inoculated with selected rhizobial strains RhOF6 and RhOF21, while the effect was not significant on beans seedling inoculated with RhOF4. This behavior of tolerant rhizobia-legumes symbioses may constitute a very important pathway to increase soil fertility and quality and can represent a friendly biotechnological way to remediate cyanotoxins contamination in agriculture.
authors: Laboratory of Biology and Biotechnology of Microorganisms, Environmental Microbiology and Toxicology Unit, Faculty of Sciences Semlalia, Cadi Ayyad University, PO Box 2390, Marrakech, Morocco.
authors: Majida
authors: M
authors: Lahrouni
authors: Khalid
authors: K
authors: Oufdou
authors: Mustapha
authors: M
authors: Faghire
authors: Alvaro
authors: A
authors: Peix
authors: Fatima
authors: F
authors: El Khalloufi
authors: Vitor
authors: V
authors: Vasconcelos
authors: Brahim
authors: B
authors: Oudra
mesh_terms: D001427:Bacterial Toxins / Q000032:analysis / Q000378:metabolism / Q000633:toxicity*; D001673:Biodegradation, Environmental / Q000187:drug effects; D004791:Enzyme Inhibitors / Q000032:analysis / Q000378:metabolism / Q000633:toxicity*; D018525:Germination / Q000187:drug effects / Q000502:physiology; D052998:Microcystins / Q000032:analysis / Q000378:metabolism / Q000633:toxicity*; D046931:Microcystis / Q000737:chemistry / Q000378:metabolism*; D009584:Nitrogen / Q000378:metabolism*; D053204:Root Nodules, Plant / Q000187:drug effects / Q000378:metabolism / Q000382:microbiology; D012639:Seeds / Q000187:drug effects / Q000382:microbiology / Q000502:physiology; D013559:Symbiosis / Q000187:drug effects / Q000502:physiology; D031307:Vicia faba / Q000187:drug effects* / Q000378:metabolism / Q000382:microbiology
chemical_list: D001427:Bacterial Toxins; D004791:Enzyme Inhibitors; D052998:Microcystins; D009584:Nitrogen