Identification and symptoms description of the main pathogens associated to cashew nut (Anacardium occidentale L.) in organic and conventional farming in Leon, Nicaragua

Abstract

This study was conducted with the objective to identify and to
describe the major causative damage agents associated to cultivated
organic and conventional cashew nut. The study was conducted
during the period from July 2009 to March 2010, in the community
of Chacraseca in the department of León. Using systematic sampling
it was assessed the incidence and severity of these damaging agents
in the area of the canopy of trees; five fixed sampling sites in
organic and conventional plots were selected. Leaves with signs and
symptoms of possible diseases were collected; leaves samples were
brought to the laboratory of Mycology of the National Agrarian
University for their respective pathologic analysis. Evaluated
variables were as follow: Incidence and severity of necrotic spots
(Pestalotiasp) by branches with leaves, incidence, and severity
of orange spots (Cephaleurossp) by branches with leaves, the
area under the disease progress curve (ABCPE) of necrotic spots
and orange spots were measured. Results were as follow: It was
identified that Pestalotiasp, and Cephaleurossp, were the main
causative agents of foliar damage in cashew nut; in this same study,
it was found a greater percentage of incidences and severity of
necrotic spots and orange spots in plots with organic management
than in plots with conventional management. The lower ABCPE
for necrotic spots are presented in plots with organic management,
and the lesser ABCPE for orange spots are presented in plots with
conventional management.

DOI: http://dx.doi.org/10.5377/calera.v12i18.1119

Revista Científica Vol. 12. Nº 18, p. 01-08 / junio 2012