Abstract

The objective of this research was to determine the capability of Aphelenchoides besseyi of being seed-transmitted in common bean. During 2007 and 2008, seeds were collected from nematode-infested common bean plants (cv. Cabécar) previously showing characteristic symptoms, in commercial plantations of the Brunca region of Costa Rica (southeastern area of the country). Between September 2008 and September 2009 the seeds were sowed in plastic pots in a greenhouse located in Veracruz, Pérez Zeledón, Costa Rica. Once seeds germinated, plants were observed weekly to determine the appearance of “amachamiento” symptoms and detect the cases of disease transmission by seed. To support the previous work, seeds from “amachamiento” diseased plants (cv. Cabécar) were collected in commercial common bean plantations in five localities of the Brunca region of Costa Rica in 2014. The seeds were carried to Estación Experimental Agrícola Fabio Baudrit Moreno of Universidad de Costa Rica located in Alajuela, where they were examined in a laboratory to determine the presence of A. besseyi specimens. Contrary to indicated for A. besseyi in rice and pastures, crops in which this pathogen is seed-transmitted, in common bean it was not possible find specimens of this nematode nor diseased plants from seeds of infested plants. The results obtained indicate that, under these experimental conditions, seeds are not an effective way for the transmission and dissemination of the “amachamiento” disease in common bean. 

Keywords: false angular leaf spot, foliar nematode, Phaseolus vulgaris L., seed pathology.