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POSTERS: Population biology and genetics

Molecular and morphological identification of Fusarium species associated with black pepper (Piper nigrum L.) in the main areas of Costa Rica
Monica Blanco-Meneses - Universidad de Costa Rica. Maria Granados- Universidad de Costa Rica, Oscar Castro-Zuniga- Universidad de Costa Rica, Gabriela Chinchilla-Salazar- Universidad de Costa Rica

Black pepper (Piper nigrum L.) has recently increased in Costa Rica, mainly as a minor crop. It has been named as one of the best qualities in the world due to the high piperin concentration. The crop is affected by aggressive soil diseases. Yellowing, leaf wilt, root rot and death of black pepper plants are symptoms associated with different species of Fusarium. Twenty nine samples from diseased plants were collected from the main areas of black pepper production, twenty one from Sarapiqui and eight from San Carlos. Diseased tissues were placed on selected medium, resulting in twenty one isolates of Fusarium spp. The characterization was performed based on morphological and molecular analysis. For the morphological identification, mycelium segments of each isolate were placed on PDA to observe the pigmentation of the colonies, and CLA to classify the macroconidia, microconidia, conidiogenous cells and chlamydospores. For the molecular identification, genomic DNA was extracted from mycelium of the twenty one isolates using the CTAB method. DNA amplification was performed using the elongation factor ? (EF-1?) region. All PCR products were sequenced and compared with the Fusarium species available in the GenBank database. Species of Fusarium solani, F. oxysporum, F. concentricum and F. proliferatum were identified and the two latter pathogen species were specific to a geographical region. The identification of these species facilitates the design of an integrated management program, in order to increase the national production of high quality black pepper.