PHENOTYPICAL CHARACTERIZATION OF FUSARIUM GUTTIFORME AND FUSARIUM
ANANATUM PATHOGENS OF THE ABACAXIZEER
Name: RAÍSSA DEBACKER MOURA
Publication date: 09/03/2017
Advisor:
| Name | Role |
|---|---|
| JOSE AIRES VENTURA (M/D) | Advisor * |
Examining board:
| Name | Role |
|---|---|
| JOSE AIRES VENTURA (M/D) | Advisor * |
| ANTONIO ALBERTO RIBEIRO FERNANDES | Co advisor * |
| PATRICIA MACHADO BUENO FERNANDES (M/D) | Internal Examiner * |
Summary: Fusarium ananatum and Fusarium guttiforme are respectively the etiological agents of
the black spot and fusariosis, important diseases of the pineapple culture. The two
species of fungi are morphologically very similar but genetically distinct. This work
aimed to identify and characterize phenotypic markers that can be used by the
phytosanitary services of Brazil and other pineapple producing countries to identify the
etiological agents of fusariosis and black spot. Were developed studies to characterize
in vitro both species at different temperatures and culture media, besides characterizing
and identifying new phenotypic markers. The ideal temperature for the development of
the species was 25°C, and also the highest production of macroconidia was in the
culture medium Basal Medium with Carboxymethylcellulose (BM+CMC) that obtained
the production of 3,2x10 5 macroconidia/ml and 1,8x10 5 macroconidia/ml for F.
ananatum and F. guttiforme, respectively. For the development of microconidia, the
Synthetic Nutrient Agar (SNA) culture medium produced a higher number of this
structure, developing 1,1x10 7 microconidia/ml and 0,7x10 7 microconidia/ml for F.
guttiforme and F. ananatum, respectively. Using fluorescence microscopy, it was
possible to observe that 78.5% of F. ananatum microconidia exhibit 1 septum, and only
8.5% of the microconidia of F. guttiform exhibit this characteristic, being a new
recommendation for the taxonomy of the species. In atomic force microscopy,
protuberances were found in the cell wall of F. guttiforme and absent in F. ananatum,
and could be characterized as a new important morphological marker for taxonomy. In
addition, the use of flow cytometry enabled the characterization of the distribution of
core in the species, which establishes uninucleate microconidia and multinucleated
macroconidia. The presence of several nuclei in macroconidia may be related to the
amount of septa in its structure. The new phenotypic markers contribute to the
taxonomy of pathogens and enable new strategies to identify the etiological agents of
these diseases.
Keywords: Taxonomy. Fungi. Ananas comosus. Microscopy. Citometry. Biotechnology
