title: Zinc deficiency affects physiological and anatomical characteristics in maize leaves.
abstract: Zinc (Zn) is an essential microelement involved in several plant physiological processes. Therefore, it is important to identify Zn deficiencies promptly--before extensive damage occurs to the plant. The diagnostic tools that are used to identify Zn deficiencies are very important in areas where Zn deficiencies occur. Such diagnostic tools are vital for nutritional management and fertilizer recommendations. The current study investigated the effects of Zn deficiency on maize plants by recording a number of physiological and anatomical parameters. A Zn omission trial (from 0 to 22 days) was carried out to produce plants that had varying degrees of Zn deficiency. Typical symptoms of Zn deficiency (e.g. chlorotic stripes and purple shades on the edges and leaf sheath) appeared 16 days after the omission of Zn from nutrient solutions. As the time of Zn omission increased, there were significant decreases in net photosynthesis, stomatal conductance, maximal efficiency of photosystem I (evaluated by Fv/Fm), biomass (dry weight) and Zn concentrations in plants. Zinc-deficient plants also had a lower vascular bundle proportion coupled with a higher stomata density. These physiological and anatomical changes negatively impacted plant growth. Moreover, they occurred before visible symptoms of Zn deficiency were observed. Zinc concentrations were recorded for younger leaves, rather than for more mature leaves, which is usually recommended for plant analysis. The results demonstrate that the analysis of Zn in young leaves of maize is a very sensitive indicator of Zn status.
authors.affiliation: Departamento de Solos, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil. Electronic address: mattiello@ufv.br.
authors.forename: Edson M
authors.initials: EM
authors.lastname: Mattiello
authors.affiliation: Departamento de Solos, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil.
authors.forename: Hugo A
authors.initials: HA
authors.lastname: Ruiz
authors.affiliation: Departamento de Solos, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil.
authors.forename: Julio C L
authors.initials: JC
authors.lastname: Neves
authors.affiliation: Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil.
authors.forename: Marília C
authors.initials: MC
authors.lastname: Ventrella
authors.affiliation: Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil; Max-Planck Partner Group at the Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil.
authors.forename: Wagner L
authors.initials: WL
authors.lastname: Araújo
mesh_terms: D018515:Plant Leaves / Q000033:anatomy & histology / Q000737:chemistry / Q000254:growth & development / Q000502:physiology; D003313:Zea mays / Q000033:anatomy & histology* / Q000737:chemistry / Q000254:growth & development / Q000502:physiology*; D015032:Zinc / Q000172:deficiency*
chemical_list: D015032:Zinc
keywords: Corn; Nutritional diagnostic; Photosynthesis