Resumo

ORTIZ-MARTINEZ, Luis Enrique et al. Fusarium sp., causal agent of vascular wilt in citrus and its sensitivity to fungicides. Rev. mex. fitopatol [online]. 2022, vol.40, n.1, pp.1-17.  Epub 03-Out-2022. ISSN 2007-8080.  https://doi.org/10.18781/r.mex.fit.2106-3.

Citrus wilt is a disease of recent appearance in the northern area of Veracruz that causes economic losses to producers in the region. The present work aimed to identify the causative agent of this disease and evaluate different fungicides to determine its in vitro sensitivity. A fungus was consistently isolated in plants with wilt symptoms; it was morphologically identified in different culture media and molecularly identified by PCR using the EF1-728F/EF1-986R primers. The fungus was inoculated in three varieties of citrus under greenhouse conditions. The sensitivity test was carried out with the fungicides chlorothalonil, benomyl thiabendazole, prochloraz, and a biological agent (Bacillus subtilis) at different concentrations, plus a negative control. Fusarium sp. (Accession No. MW438335) was morphologically and molecularly identified as the causal agent of vascular wilt in citrus fruits, causing growth retardation, decreased number of roots, wilting of the apical bud, and necrosis in the vascular system of the three varieties inoculated. The most effective fungicides in inhibiting mycelial growth were thiabendazole, prochloraz, and the biological agent Bacillus subtilis.

Palavras-chave : Identification; morphology; Koch’s postulates; in vitro control.