Peronospora hyoscyami f. Sp. tabacina. Variabilidad morfológica en esporangios de aislados (II)

tobacco blue mold which is caused by peronospora hyoscyami f. sp. tabacina is the most devastating tobacco crop disease in cuba. this is expressed by the huge losses that it causes annually to this crop. the high adaptability to environmental conditions that shows this fungus, and the strong outbreaks caused by it even under adverse development conditions for the disease in cuba, motivated behavioral studies of different isolates of this microorganism, which were obtained from several tobacco plantations located in different regions of the country. phenotypical markers were used as a baseline for this study. a laboratory assay was conducted during the 2002-2003 and 2003-2004 seasons in order to determine the variability of p. hyoscyami f. sp tabacina in cuba. isolates were collected from tobacco growing areas located in the provinces of pinar del río, la habana and matanzas in western region of the island, cienfuegos and ciego de ávila in central region and holguín in the eastern region. sporangia were measured for all the isolates and marked deformities were registered. this deformity was significantly atypical in the isolates obtained from pinal del río, la habana, cienfuegos and ciego de ávila.