Caracterizaˋˋo morfofisiol車gica e identificaˋˋo molecular de isolados de Guignardia citricarpa, agente patog那nico da mancha preta dos citros

作者：Caixeta; Marilda Pereira; Corazza; Maria Julia; Oliveira; Ricardo Ribeiro de; Zanutto; Carlos Alexandre; Nunes; William Mario de Carvalho; Vida; Joo Batista

来源：Acta Scientiarum - Agronomy, 2008.

DOI：10.1590/S1807-86212008000500004

• g. citricarpa
• pcr
• sporing
• mycelial growth
• temperature
• mean of culture
• photoperiod.

the present work aims to identify 11 isolates of guignardia citricarpa, the causal agent of the citrus black spot (cbs), obtained from affected fruit in different geographical regions, through pc r and morphophysiological characterization of propagative structures, sporing and mycelial growth in different means of culture, temperatures and photoperiods, under laboratory conditions. through the pcr test, all isolates were identified as being the g. citricarpa pathogen. the characterized isolates were subjected to evaluations at temperatures of 20, 25 and 30oc, in continuous light, continuous darkness, and alternating 12 hours light and 12 hours darkness, during 24 days. the study used oat-agar (oa), potato-dextrose-agar (pda) and carrot-dextrose-agar (cda) as means of culture. the results showed an interaction between the different means of culture, temperatures and photoperiods. the mean of culture that best stimulated mycelial growth was cda at 25oc under the 12-hour photoperiod. the greatest spore (conidia) production was verified in pda at 20oc in the 12-hour photoperiod. there was no sporing of any isolate in the cda mean of culture. under the 30oc temperature, the study verified only the production of hyphae and picnids in most isolates, in all means of culture and photoperiods.