SciELO - Scientific Electronic Library Online

 
vol.69 issue3Fate of copper in intensive shrimp farms: bioaccumulation and deposition in pond sedimentsReproductive performance of Palmistichus elaeisis Delvare and LaSalle (Hymenoptera: Eulophidae) with previously refrigerated pupae of Bombyx mori L. (Lepidoptera: Bombycidae) author indexsubject indexarticles search
Home Pagealphabetic serial listing  

Brazilian Journal of Biology

Print version ISSN 1519-6984

Abstract

SILVA-STENICO, ME. et al. Nutritional deficiency in citrus with symptoms of citrus variegated chlorosis disease. Braz. J. Biol. [online]. 2009, vol.69, n.3, pp. 859-864. ISSN 1519-6984.  http://dx.doi.org/10.1590/S1519-69842009000400013.

It is well known that citrus plants that have been infected by Xylella fastidiosa display nutritional deficiencies, probably caused by production of extracellular polymers by the bacteria that block normal nutrient flow through the xylem. The aim of this work was to study the mineral composition of specific foliar areas in different stages of infection in citrus. Thus, the concentrations of macro and micronutrients in leaves of citrus infected by X. fastidiosa were measured. Samples from four infected citrus orchards in the State of São Paulo, Brazil, were respectively collected from Santa Rita do Passa Quatro, Neves Paulista, Gavião Peixoto and Paraíso counties. The presence of X. fastidiosa in leaves was confirmed by polymerase chain reaction (PCR) using specific PCR primers. To understand the variation in leaf-nutrient content in citrus plants, we used foliar nutrient values from control (non-symptomatic) plants as a reference. Chemometric analysis showed that the deficiency of P and K in symptomatic trees for all orchards and high concentrations of Fe, Mn and Zn were observed in chlorotic areas, although other studies revealed deficiency of zinc in leaves. This is the first report showing that a correlation between chlorotic citrus leaf and higher concentrations of Fe, Mn and Zn are observed when infected and healthy plants were compared.

Keywords : citrus; nutrition; Xylella fastidiosa; CVC disease; chemometry.

        · abstract in Portuguese     · text in English     · pdf in English