title: Toxigenic profiles and trinucleotide repeat diversity ofFusariumspecies isolated from banana fruits.
abstract: InfestingFusariumspecies isolated from banana fruit samples were identified and quantified by morphological, mycotoxicological and molecular tools. A total of 19Fusariumisolates were obtained:F. semitectumwas most predominant (26%), followed byF. proliferatum(16%),F. circinatum(16%),F. chlamydosporum(10.5%),F. solani(10.5%),F. oxysporum(10.5%) andF. thapsinum(5%). Fumonisin B1, deoxynivalenol and zearalenone contents were assayed by high-performance liquid chromatography (HPLC). Seventeen isolates, belonging toF. chlamydosporum,F. circinatum,F. semitectum,F. solani,F. thapsinum,F. proliferatumandFusariumspp., produced mycotoxins when cultured on rice medium. Fumonisin was produced by all of the studiedFusariumisolates, exceptF. oxysporum, at a concentration of over 1 μg/mL.F. citriniumisolates 4 and 5 andF. solaniisolate 3 were the most potent producers of deoxynivalenol. We compared the 19Fusariumisolates based on the bands amplified by 10 microsatellite primers. Of these, seven primers, (TCC)5, (TGG)5, (GTA)5, (ATG)5, (TAC)5, (TGC)5 and (TGT)5, yielded a high number of bands and different mean number of alleles. The similarity level between isolates was calculated using a simple matching coefficient. Dendrograms were constructed by the unweighted pair-group method with arithmetical averages (UPGMA). Two main clusters were observed. The interspecific genetic similarity betweenFusariumspp. isolates was between 40% and 58% and the intraspecific similarity from 58% to 100%, indicating a high degree of genetic diversity in the tested isolates. Some unexpected genetic similarities were observed among the isolates, indicating non-agreement between morphological and molecular identification of the isolates.
authors.affiliation: Biology Department, Science and Humanities College, Shaqra University , Shaqra , Saudi Arabia.
authors.forename: Mousa Abdullah
authors.initials: MA
authors.lastname: Alghuthaymi
authors.affiliation: Botany and Microbiology Department, Faculty of Science, King Saud University , Riyadh , Saudi Arabia.
authors.forename: Ali Hassan
authors.initials: AH
authors.lastname: Bahkali
keywords: Fusarium; ISSR analysis; banana fruits; microsatellite markers; mycotoxin