Activity of Lectins on the Growth of Phytopathogenic Fungi
Antifungal activity. VML and PPL lectins.
Plant lectins have been widely used in the biochemistry, pharmacology and medicine areas. However, their antifungal activity upon phytopathogenic fungi is so far little studied. Therefore, this work aimed to evaluate the activity of Vatairea macrocarpa lectin (VML) and Parkia platycephala lectin (PPL) on the growth of Rhizoctonia solani, Lasiodiplodia theobromae and Colletotrichum brevisporum. For that, the lectins were purified by affinity chromatography, then lyophilized and tested for purity by SDS-PAGE. The fungal isolates were obtained from the CFC Phytopathogenic Fungi Collection. As positive controls, the fungicides Pencicuron and Thiophanate-Methyl were used. Statistical analysis showed that the medium with NaCl did not prevent fungal growth, while fungicides reduced or prevented the growth of isolates, with the exception of CMM - 1976, for which Thiophanate-Methyl had no effect. The VML (1000 μg/mL) and PPL (100 μg/mL) lectins were not effective in reducing the growth of the tested isolates. Nonetheless, PPL (200 μg/mL) reduced the fungal growth of both CFC - 0516 and CMM - 4065 compared to the control. Taken together, our results spur further research in the experimental area with lectins in order to establish efficacy strategies of possible chemical formulations for the control of diseases caused by fungi in plants.