title: Assessment of the impact of Aluminum on germination, early growth and free proline content in Lactuca sativa L.
abstract: Aluminum (Al) toxicity is a major problem in crop production on acid soils. The use of industrial or municipal wastewaters, which may be contaminated with metals, for irrigation in agriculture is common over the world. This action can increase the concentration of these agents in the soil and decrease crops yields. In order to evaluate the toxicological effects of recommended Al levels in irrigation water, under acidic conditions, on lettuce, seeds of two cultivars ("cv Reine de Mai" and "cv White Boston") were exposed to five different Al concentrations (0, 0.05, 0.5, 5 and 20mg/L) and germination percentage, root and shoot lengths were measured. Also, the germination rate and the vigor index were calculated, and the proline content was estimated for all concentrations. Results showed that seed germination was not negatively affected by Al, but the germination rate decreased in both cultivars. For the other factors analyzed, with the exception of 20mg/L concentration for "cv White Boston", Al induced, in general, negative effects including the content of proline that increased in the seeds that were exposed to this metal. The "cv Reine de Mai" was more sensitive for the analyzed concentrations than the other cultivar.. The results indicated that even recommended Al concentrations for irrigation, under acidic conditions, can interfere negatively in seed germination and seedling establishment and possibly with crop production.
authors.affiliation: Department of Genetics and Biotechnology, University of Trás-os-Montes and Alto Douro, Quinta dos Prados, 5000-801 Vila Real, Portugal. Electronic address: patricia.curado1317@gmail.com.
authors.forename: Patrícia
authors.initials: P
authors.lastname: Silva
authors.affiliation: Department of Genetics and Biotechnology, University of Trás-os-Montes and Alto Douro, Quinta dos Prados, 5000-801 Vila Real, Portugal; University of Lisboa, Faculty of Sciences, BioISI- Biosystems & Integrative Sciences Institute, Campo Grande, Lisboa, Portugal. Electronic address: mmatos@utad.pt.
authors.forename: Manuela
authors.initials: M
authors.lastname: Matos
mesh_terms: D057914:Agricultural Irrigation; D000383:Agriculture; D000535:Aluminum / Q000633:toxicity*; D000704:Analysis of Variance; D018556:Crops, Agricultural / Q000187:drug effects; D018525:Germination / Q000187:drug effects*; D018545:Lactuca / Q000187:drug effects* / Q000254:growth & development; D018517:Plant Roots / Q000187:drug effects; D011392:Proline / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism; D036226:Seedlings / Q000187:drug effects; D012639:Seeds / Q000187:drug effects; D012987:Soil / Q000737:chemistry; D012989:Soil Pollutants / Q000633:toxicity; D062065:Wastewater / Q000633:toxicity
chemical_list: D000535:Aluminum; D011392:Proline; D017382:Reactive Oxygen Species; D012987:Soil; D012989:Soil Pollutants; D062065:Wastewater
keywords: Aluminum; Early growth; Germination; Irrigation water; Proline