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Chickpea (Cicer arietinum L.) is an important food legume worldwide, providing a source of high-quality protein. Fifteen chickpea samples showing leaf yellowing and root rot were obtained from southern Alberta, Canada, in 2018. Twenty single-spore Fusarium isolates were obtained from those samples. Based on the morphological characteristics, five species of Fusarium were identified, with F. redolens as the predominant species (11 isolates), followed by F. culmorum (3), F. sporotrichioides (3), F. oxysporum (2) and F. equiseti (1). The identification of each isolate was confirmed using partial sequences of the translation elongation factor 1-alpha (EF-1α) gene. Each EF-1α sequence displayed 99.54% to 100% similarity to sequences for each corresponding species in the GenBank database. The Fusarium isolates were tested for pathogenicity on chickpea 'CDC Frontier' in a greenhouse. Isolates recovered from inoculated plants were confirmed as the respective Fusarium species, fulfiling Koch's postulates. Selected isolates of each Fusarium species were able to infect common crops including barley, corn, canola, and lentil in Alberta. This is the first report of F. redolens on chickpea in Alberta, F. equiseti on chickpea in Canada, and F. culmorum and F. sporotrichioides on chickpea in the world. [ABSTRACT FROM AUTHOR]

Root rot is an important disease of field pea (Pisum sativum L.) on the Canadian Prairies. The composition and alternative crop hosts of fungal and oomycete communities colonizing pea residues from Alberta and Manitoba were studied in field trials over two years. Standing pea residues were sampled from diseased and asymptomatic patches of 17 commercial fields in 2013 and 2014 after harvest and again in early spring the following year prior to seeding. The pea residue was ground to a powder and mixed with sterile Cornell potting mix. Plants of pea, wheat, and canola were grown in this mixture under controlled conditions. The root rot severity on each plant was evaluated and sections from diseased roots were plated on agar medium. Fungal and oomycete communities isolated from symptomatic roots were identified based on culture morphology and PCR analysis. About 3000 fungal isolates, belonging to some 50 species, were identified. Canola was less susceptible to infection than pea or wheat. Fusarium avenaceum (Fr.) Sacc. was the most abundant species infecting the three hosts; F. culmorum (Wm.G.Sm.) Sacc. and Bipolaris sorokiana (Sacc.) Shoemaker were more frequently isolated from wheat, and F. solani (Mart.) Sacc., F. oxysporum Schlecht. and Aphanomyces euteiches Drechsler were more frequently isolated from pea. Pathogen communities from asymptomatic and diseased patches of fields were similar. Overall, composition of the fungal community changed over winter, but the most abundant species did not change. The results show that multiple pathogens, and particularly Fusarium spp., can survive overwinter on pea residue. [ABSTRACT FROM AUTHOR]

Root rot is a concern in the pea growing areas of Canada and elsewhere in the world, since it can cause significant yield loss. Fusarium spp. are considered major pea root rot pathogens. In this study, the pathogenicity and host range of Fusarium species collected from earlier surveys of commercial pea fields in Alberta were evaluated. Forty-five isolates belonging to six Fusarium species were selected for pathogenicity testing under greenhouse conditions. Fusarium solani f. sp. pisi and F. avenaceum were the most aggressive species, followed by F. oxysporum, F. culmorum and F. redolens. Due to their ability to cause severe disease on pea, F. solani f. sp. pisi and F. avenaceum were chosen for further testing on other common rotational crops grown in Alberta, and 10 cereal, oilseed and pulse crops were inoculated with isolates of those species. Both F. solani f. sp. pisi and F. avenaceum caused significant disease symptoms on pea, chickpea, dry bean and faba bean, but not on cereal crops, soybean, green lentil or canola when compared with their respective non-inoculated controls. Fusarium avenaceum, but not F. solani f. sp. pisi, caused significant root rot symptoms on red lentil, although disease severity was low. New information on the host range of these root rot pathogens will be valuable for choosing appropriate disease management strategies. [ABSTRACT FROM AUTHOR]