Incidence, Molecular Characteristics and Pathogenicity of Gibberella fujikuroi Species Complex Associated with Rice Seeds from Asian Countries

Abstract

Gibberella fujikuroi species complex (GFSC) was isolated from rice (Oryza sativa L.) seed samples from ten Asian countries and investigated for incidence of GFSC, molecular characteristics, and pathogenicity. Regardless of geographic origin, GFSC was detected with incidences ranging from 3% to 80%. Four species, Fusarium fujikuroi, F. concentricum, F. proliferatum, and F. verticillioides, were found to show an association with rice seeds, with F. fujikuroi being the predominant species. In phylogenetic analyses of DNA sequences, no relationship was found between species, isolates, and geographic sources of samples. Unidentified fragments of the β-tubulin gene were observed in ten isolates of F. fujikuroi and F. verticillioides. With the exception of three isolates of F. fujikuroi, F. fujikuroi, F. proliferatum, and F. verticillioides were found to have FUM1 (the fumonisin biosynthetic gene); however, FUM1 was not found in isolates of F. concentricum. Results of pathogenicity testing showed that all isolates caused reduced germination of rice seed. In addition, F. fujikuroi and F. concentricum caused typical symptoms of bakanae, leaf elongation and chlorosis, whereas F. proliferatum and F. verticillioides only caused stunting of seedlings. These findings provide insight into the characteristics of GFSC associated with rice seeds and might be helpful in development of strategies for management of bakanae.

The puzzle of bakanae disease through interactions between Fusarium fujikuroi and rice

“…could also be present on rice, but at a lower incidence. In particular, two species of GFSC, F. verticillioides and F. proliferatum, have been isolated in different rice areas in the world (10,30,31), and these species have also been considered as thebakanae-disease causative agents for decades. Since some species belonging to GFSC are morphologically indistinguishable (e.g.…”

“…Yield losses ranging from 5 to 15%, with an increasing trend, have also been found in Italy, the main European rice producer (219,500 ha and 1,386,100 t in 2014). Bakanae disease continues to spread throughout the world on rice, with reports in California (8), FYR Macedonia (9), Russia, the Philippines and Thailand (10). F. fujikuroi has also been isolated from other hosts, such as grapevine (Vitis vinifera), little bluestem (Andropogon scoparius Michx.)…”

Multi-Homologous Recombination-Based Gene Manipulation in the Rice Pathogen Fusarium fujikuroi

“…The fungal species belongs to the mating population (MP)-C of the Gibberella fujikuroi species complex, which is composed of more than eleven MPs that are sexually infertile with one another ( Bomke et al, 2008 ). It is known to produce fumonisin ( Cruz et al, 2013 ; Jeon et al, 2013 ), moniliformin ( Desjardins et al, 2000 ), and beauvericin ( Desjardins et al, 2000 ). In addition to typical bakanae symptoms, a considerable number of strains or isolates trigger stunting in rice ( Cruz et al, 2013 ; Hur et al, 2015 ; Jeon et al, 2013 ).…”

Molecular strategies for detection and quantification of mycotoxin‐producing Fusarium species: a review

“…Some Fusarium species are worldwide pathogens of Fusarium head blight, which leads to serious reductions of product yield and loss of grain quality. 3 -5 Fusarium species have been frequently isolated from the Gibberella fujikuroi complex, mainly composed of F. verticillioides and F. graminearum, 6,7 which can generate fumonisins and trichothecenes that can contaminate cereals and/or many other foods, and finally affect the human and animal health via the food chain. 8 Conventional identification of toxigenic Fusarium species has been performed mainly based on morphological and cross-fertility criteria, 9 although recognition of morphological characters are, sometimes, not enough to accurately identity fungal isolates at the species level.…”