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The association of Fusarium sp. with agricultural seeds is a limiting factor for the uniform establishment of the crop. The aim of this work was to identify six isolates of Fusarium at the species level, based on morphological and molecular markers (TEF-1α and βtub); and to verify the pathogenicity of these isolates to the seeds of Crambe abyssinica (crambe). The pathogenicity test was carried out through the contact of the seeds with the fungal culture for 48 hours, followed by sowing in sand. The variables evaluated were: percentage of emergence at 30 days and damping off. The Fusarium species identified were F. solani (FCa/3, FCa/7.2 and FCa/10) and F. oxysporum (FCa/4, FCa/2 and FCa/8). The FCa/3, FCa/4 and FCa/7.2 isolates were pathogenic to crambe seedlings, causing reduction in the percentage of emergence and damping off. [ABSTRACT FROM AUTHOR] more...

Plant extracts may assist in controlling plants diseases due to its antimicrobial activity and activation of defense mechanisms. This study aimed to evaluate the effect of aqueous extracts of garlic and rosemary, autoclaved or non autoclaved, on the mycelial growth of Colletotrichum lindemuthianum, production of phaseollin by beans and severity of anthracnose in the field. The fungus was incubated in medium containing the extracts and its growth measured for 18 days. For phaseollin evaluation the extracts were applied on bean hypocotyls, the phytoalexin extracted in ethanol and read in spectrophotometer. The severity of anthracnose was evaluated in bean plants sprayed with the extracts and inoculated with the fungus. For the garlic extract, the greater reduction (57,6%) in micelial growth was at 3% in the non autoclaved extract, as for the rosemary extract, the greater reduction (18,6%) was in the autoclaved extract. Autoclaving had no effect on the induction of phaseollin. At field conditions, the extracts did not reduce significantly the severity of anthracnose. The non autoclaved garlic extract showed to be more efficient in reducing the mycelial growth of C. lindemuthianum, while rosemary, autoclaved or not, proved to be more effective in the induction of phaseollin. [ABSTRACT FROM AUTHOR] more...