title: Morphophysiological, ultrastructural, and nutritional changes induced by Cu toxicity in young Erythrina fusca plants.
abstract: Erythrina fusca is an important legume used for shade cover in cacao plantations in Brazil. Cacao plantations receive large quantities of copper (Cu)-containing agrochemicals, mainly for control of diseases. Therefore, Cu toxicity was investigated in seedlings grown in hydroponics with increasing concentrations of Cu (0.005-32 mg L-1) in a greenhouse. Ultrastructural analyses showed cell plasmolysis in the root cortical area and changes in thylakoid membranes at 8 mg Cu L-1and higher. There were changes in epicuticular wax deposition on the leaf surface at the 16 and 32 mg Cu L-1treatments. Leaf gas exchanges were highly affected 24 hours after application of treatments beginning at 8 mg Cu L-1and higher Cu concentrations. Chemical analyses showed that Cu content in E. fusca roots increased as Cu concentration in the nutrient solution increased, whereas the shoot did not show significant changes. It is also observed that excess Cu interfered with Zn, Fe, Mn, Mg, K, P, and Ca content in the different E. fusca organs. Investigation of Cu toxicity symptoms focusing on morphophysiological, ultrastructural, gas exchange, and nutritional changes would be useful to alleviate Cu toxicity in E. fusca under field conditions, an important agroforestry species in cacao plantation.
authors.affiliation: a Instituto Federal da Bahia, campus Eunápolis , Rosa Neto, Eunápolis , BA , Brazil.
authors.forename: Vânia L
authors.initials: VL
authors.lastname: Souza
authors.affiliation: b Universidade Estadual de Santa Cruz, Departamento de Ciências Biológicas , Ilhéus , BA , Brazil.
authors.forename: Alex-Alan F
authors.initials: AF
authors.lastname: de Almeida
authors.affiliation: b Universidade Estadual de Santa Cruz, Departamento de Ciências Biológicas , Ilhéus , BA , Brazil.
authors.forename: Pedro A O
authors.initials: PAO
authors.lastname: Mangabeira
authors.affiliation: b Universidade Estadual de Santa Cruz, Departamento de Ciências Biológicas , Ilhéus , BA , Brazil.
authors.forename: Delmira da C
authors.initials: DDC
authors.lastname: Silva
authors.affiliation: b Universidade Estadual de Santa Cruz, Departamento de Ciências Biológicas , Ilhéus , BA , Brazil.
authors.forename: Raildo M
authors.initials: RM
authors.lastname: de Jesus
authors.affiliation: b Universidade Estadual de Santa Cruz, Departamento de Ciências Biológicas , Ilhéus , BA , Brazil.|c CEPEC/CEPLAC , Ilhéus , BA , Brazil.
authors.forename: Raúl René
authors.initials: RR
authors.lastname: Valle
mesh_terms: D001673:Biodegradation, Environmental; D001938:Brazil; D003300:Copper / Q000633:toxicity*; D004785:Environmental Pollutants / Q000633:toxicity*; D004895:Erythrina / Q000254:growth & development / Q000502:physiology; D018517:Plant Roots; D036226:Seedlings
chemical_list: D004785:Environmental Pollutants; D003300:Copper
keywords: heavy metal; photosynthesis; shade cover species