METHODS AND RESULTS: One-hundred and thirteen microfungi isolates were obtained from fruit rot infected banana in Peninsular Malaysia. However, this study was focused on the dominant number of the discovered microfungi that belongs to the genus Fusarium; 48 isolates of the microfungi have been identified belonging to 11 species of Fusarium, namely Fusarium incarnatum, Fusarium equiseti, Fusarium camptoceras, Fusarium solani, Fusarium concolor, Fusarium oxysporum, Fusarium proliferatum, Fusarium verticillioides, Fusarium sacchari, Fusarium concentricum and Fusarium fujikuroi. All Fusarium isolates were grouped into their respective clades indicating their similarities and differences in genetic diversity among isolates. Out of 48 Fusarium isolates tested, 42 isolates caused the fruit rot symptom at different levels of severity based on Disease Severity Index (DSI). The most virulent isolate was F. proliferatum B2433B with DSI of 100%.
CONCLUSIONS: All the isolated Fusarium species were successfully identified and some of them were confirmed as the causal agents of pre- and postharvest fruit rot in banana across Peninsular Malaysia.
SIGNIFICANCE AND IMPACT OF THE STUDY: Our results will provide additional information regarding new report of Fusarium species in causing banana fruit rot and in the search of potential biocontrol agent of the disease.
METHODS/FINDINGS: Blastocystis in stool samples were cultured followed by isolation, PCR amplification of a partial SSU rDNA gene, cloning, and sequencing. The DNA sequences of isolated clones showed 98.3% to 100% identity with the reference Blastocystis isolates from the Genbank. Multiple sequence alignment showed polymorphism from one to seven base substitution and/or insertion/deletion in several groups of non-identical nucleotides clones. Phylogenetic analysis revealed three assemblage subtypes (ST) with ST1 as the most prevalent (51.1%) followed by ST2 (24.4%), ST3 (17.8%) and mixed infections of two concurrent subtypes (6.7%).
BLASTOCYSTIS: ST1 infection was significantly associated with female (P = 0.009) and low educational level (P = 0.034). ST2 was also significantly associated with low educational level (P= 0.008) and ST3 with diarrhoea (P = 0.008).
CONCLUSION: Phylogenetic analysis of Libyan Blastocystis isolates identified three different subtypes; with ST1 being the predominant subtype and its infection was significantly associated with female gender and low educational level. More extensive studies are needed in order to relate each Blastocystis subtype with clinical symptoms and potential transmission sources in this community.