TITLE:
Disease Prevalence and Symptoms Caused by Alternaria tenuissima and Pestalotiopsis guepinii on Blueberry in Entre Ríos and Buenos Aires, Argentina
AUTHORS:
Rocío L. Fernández, Marta C. Rivera, Bruno Varsallona, Eduardo R. Wright
KEYWORDS:
Blueberry, Diseases, Alternaria tenuissima, Pestalotiopsis guepinii, Argentina
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.6 No.19,
December
9,
2015
ABSTRACT: About 60% of blueberry (Vaccinium corymbosum) plantations in Argentina are located in the provinces
of Entre Ríos and Buenos Aires. Alternaria tenuissima and Pestalotiopsis guepinii have been
reported as pathogens of blueberry, causing leaf spots and branch cankers. The aims of this research
were to estimate the prevalence of these microorganisms on leaves and fruits taken from crops located
in Entre Ríos and Buenos Aires, as well as to differentiate leaf symptoms after target inoculations
with each pathogen individually and in mixtures. Both fungi were present in blueberry fields
from 2010 to 2013. A. tenuissima was the most prevalent pathogen, as most of the symptoms detected
in the fields had been caused by this species. As a result of inoculations on cv. O’Neal, injured
tissues showed symptoms before undamaged ones. Leaf symptoms caused by A. tenuissima differed
from those caused by P. guepinii because of their predominant reddish color and the absence of
drop-off of the central part of the lesions. When inoculated in a mixture, incubation period on leaves
was intermediate between the registered for individual inoculations. The leaves showed reddishbrown
spots typical of A. tenuissima and dark brown spots typical of P. guepinii, both with red margins.
Blight, defoliation and canker symptoms caused in each case were undistinguishable.