Identification, Pathogenicity, and Genetic Diversity of Fusarium spp. Associated with Maize Sheath Rot in Heilongjiang Province, China

Abstract

Maize sheath rot is a prevalent maize disease in China. From 2020 to 2021, symptomatic samples were collected from the main maize-growing regions of Heilongjiang province. To clarify the population and genetic diversity, as well as the virulence of pathogens responsible for maize sheath rot, a total of 132 Fusarium isolates were obtained and used for follow-up studies. Ten Fusarium species were identified based on morphological characteristics, and phylogenetic analysis was conducted using the TEF-1α gene sequences, including F. verticillioides (50.00%), F. subglutinans (18.94%), the Fusarium incarnatum-equiseti species complex (14.39%), F. temperatum (5.30%), F. acuminatum (3.03%), F. solani (2.27%), F. sporotrichioides (2.27%), F. tricinctum (1.52%), F. asiaticum (1.52%), and F. proliferatum (0.76%). All 10 Fusarium species could produce oval-to-annular lesions on maize sheath, and the lesions were grayish yellow to dark brown in the center and surrounded by a dark gray-to-dark brown halo. Of these, F. tricinctum and F. proliferatum showed significantly higher virulence than the other Fusarium species. In addition, haplotype analysis based on the concatenated sequences of the ITS and TEF-1a genes showed that 99 Fusarium isolates which belonged to the Fusarium fujikuroi species complex—consisting of F. verticillioides isolates, F. subglutinans isolates, F. temperatum isolates, and F. proliferatum isolates—could be grouped into 10 haplotypes, including 5 shared haplotypes (Haps 1, 2, 4, 5, and 6) and 5 private haplotypes (Haps 3, 7, 8, 9, and 10). Furthermore, the F. verticillioides clade in the haplotype network was radial with the center of Hap 2, suggesting that population expansion occurred. This research showed that Fusarium species associated with maize sheath rot in Heilongjiang province are more diverse than previously reported, and this is the first time that F. subglutinans, F. temperatum, F. solani, F. sporotrichioides, F. tricinctum, and F. acuminatum have been confirmed as the causal agents of maize sheath rot in Heilongjiang province.

Relationship between Dubas Bug (Ommatissus lybicus) Infestation and the Development of Fungal-Induced Leaf Spots in Date Palms (Phoenix dactylifera)

“…Fusarium is a widely distributed pathogen in different crops in different parts of the world. Fusarium fujikuroi is a pathogen of rice seeds [ 49 ], maize sheath rot [ 50 ], round spot disease of Zanthoxylum armatum [ 51 ], and brown leaf spot on kiwifruit [ 52 ]. Fusarium humuli has been reported to cause wilt in yams in China [ 53 ], while F. microconidium is a recently described species with unknown origin and unknown substrate, with an ex-type culture located in the Centraal Bureau voor Schimmelcultures (CBS) culture collection (CBS 119843 = MRC 8391) [ 54 ].…”

A Study of Soil-Borne Fusarium Wilt in Continuous Cropping Chrysanthemum Cultivar ‘Guangyu’ in Henan, China

“…Healthy chrysanthemum plants ("Guangyu" cultivar) that remained asymptomatic after three generations of consecutive cutting and transplanting in an indoor environment were chosen as the inoculated hosts [20]. The method described by Getha et al [21] was employed to determine which Fusarium species were responsible for inducing plant disease.…”