ABSTRACT The genus Fusarium causes several diseases in grasses such as sugarcane and is characterised by high genetic variability and adaptability. Despite being the world's largest producer of sugarcane, Brazil still lacks information on Fusarium species diversity in its major producing regions. The species identity of 56 Brazilian Fusarium isolates recovered from Brazilian sugarcane was determined using DNA sequences of fragments of the partial TEF‐1α and RPB2 genes, and their population genetic structure was assessed by amplified fragment length polymorphism (AFLP) analysis. The DNA polymorphism of partial TEF ‐ 1α gene sequences of Brazilian F. sacchari isolates was additionally compared with sequences deposited in the NCBI GenBank database originating from China, India, Malaysia and Iran to evaluate genetic diversity. Seven Fusarium species were identified, with a significant dominance of F. sacchari (64.3%). The species belonged to the Fusarium fujikuroi species complex (FFSC, five species) and the Fusarium incarnatum‐equiseti species complex (FIESC, two species). Based on TEF‐1α sequences, a high genetic differentiation ( F ST = 18%) was observed for F. sacchari among countries. Sixteen haplotypes were identified, with the prevalence of one haplotype (60.4%) despite their geographical separation. The AFLP‐based genetic structure of the 56 isolates indicated three genetic clusters ( K = 3), with moderate genetic diversity. This study advances the understanding of Fusarium spp. diversity and population structure, contributing to the development of integrated disease management strategies.
Soares et al. (Sun,) studied this question.