Characterization of Fusarium species causing dry rot of potato mini tubers produced by biotechnological approaches

Soil-borne diseases affect potatoes and cause severe damage to tubers. Several Fusarium species have been associated as causal agents of potato dry rot. This research focused on characterizing fungal species causing dry rot in potato mini tubers produced using biotechnological approaches. Minitubers with typical symptoms of tuber dry rot were selected from freeze store chambers at Instituto de Biotecnología de las Plantas and processed in the applied microbiology laboratory. Potato Dextrose Agar (PDA, Fluka) with components reduced by 50% was used for fungal isolation, and Spezieller Nährstoffarmer Agar (SNA) was used for morphological characterization. Ten isolates were obtained from potato mini tubers. Mycelia growth was speedy in the culture media used, and CCIBP-Fp-1 had the greatest growth velocity. Cottony colonies were observed in isolates CCIBP-Fp-1, CCIBP-Fp-6, CCIBP-Fp-7 and CCIBP-Fp-9; felty texture was common in isolates CCIBP-Fp-2, CCIBP-Fp-3, CCIBP-Fp-4 and CCIBP-Fp-8, while subfelty texture was seen in isolates CCIBP-Fp-5 and CCIBP-Fp-10. CCIBP-Fp-2 and CCIBP-Fp-4 isolates showed characteristics similar to Fusarium solani, while CCIBP-Fp-3, CCIBP-Fp-5, CCIBP-Fp-6, CCIBP-Fp-7, CCIBP-Fp-8, CCIBP-Fp-9 and CCIBP-Fp-10 corresponded with Fusarium oxysporum. With the results of this work, potato tuber seeds may be protected with better conservation procedures and improve the health of Cuban Potato seeds produced by biotechnological approaches. Keywords: biotechnology; fungi; post-harvest; Solanum tuberosum