TITLE:
Identification of Alternaria spp. as Pathogenic on the Native Species Terminalia australis and Salvia guaranitica
AUTHORS:
Mariana Kameniecki, Eduardo R. Wright, Marta C. Rivera
KEYWORDS:
Alternaria tenuissima; Terminalia australis; A. alternata; Salvia guaranitica; Diagnosis
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.4 No.6A,
June
19,
2013
ABSTRACT: This work is the result of activities included
in the cooperative project between Asociación Ribera Norte (ARN) and the
Department of Plant Pathology, School of Agronomy, University of Buenos Aires.
ARN is a non-governmental organization
created in 1993 mainly for the management of the Reserva Ecológica Municipal
Ribera Norte, a preservation area located in San Isidro (North of
Buenos Aires), within the Provincia Paranaense region. The aims were to
identify diseases in native plant species growing there. Light brown leaf spots
with thin brown margins and narrow yellow halos were observed on Terminalia australis (mean disease
severity: 25%). The pathogen was isolated, inoculated on healthy plants,
reisolated from infected leaves and identified as Alternaria
tenuissima. Similarly, another
leaf-spot disease was observed on Salvia guaranitica, characterized by
reddish brown large spots developed from the apexes and margins towards the
centre of the leaves, reaching the veins in some cases (mean severity: 20%). Pathogen isolation,
inoculation and reisolation led to the identification of A.
alternata as the causal agent of
the disease. Unusual heavy rain is analyzed as disease conductive.