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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]

A survey was conducted in southern Alberta, Canada, to collect Fusarium stalk rot and Fusarium head blight (FHB) disease samples from corn and wheat fields, respectively, with an aim to understand the diversity in the population of Fusarium graminearum. From 77 wheat and 80 corn samples, 79 isolates of F. graminearum were obtained. These 79 isolates were evaluated for their growth rate, sporulation ability, pathogenicity and trichothecene genotype. Eighty-two percent of the isolates were recovered from corn, which suggests corn residue may be better suited than wheat for perpetuating the FHB pathogen. Three genotypes with potential of producing 3-ADON, 15-ADON and NIV were present in the population, and among them, 15-ADON producing genotype was predominant, and 3-ADON genotype produced more spores than the 15-ADON genotype. The proportion of 3-ADON genotype is increasing overtime in Alberta. The impact of increasing population of 3-ADON genotype is worthy of to be monitored for the management of FHB. There were variations in the population of F. graminearum isolates for growth rate, sporulation and pathogenicity but revealed no association among the parameters suggesting other factors like host susceptibility and environment play a significant role in the development of FHB. [ABSTRACT FROM AUTHOR]

A simple and accurate PCR protocol for identification of Fusarium graminearum from fungal cultures was developed. In this protocol, DNA extraction was omitted by using the Thermo Scientific Phire direct PCR master mix kit for template preparation and PCR. Two primer pairs, ITS5/ITS2 for DNA template quality control and Fg16F/Fg16R for F. graminearum identification, were used in a duplex PCR. Each 20-µL PCR contained 10 µL 2× Phire Direct PCR master mix, 2 µL template and 0.25 µM each of the four primers. The PCR program consisted of an initial denaturation at 98°C for 5 min, followed by 40 cycles of denaturation at 98°C for 5 s, annealing at 62°C for 5 s and extension at 72°C for 20 s, and a final extension at 72°C for 1 min. This protocol was used to test 196 fungal cultures isolated from 75 wheat samples. Fourteen cultures were identified as F. graminearum. This protocol was demonstrated to be simpler and more accurate than other PCR protocols for F. graminearum identification. [ABSTRACT FROM AUTHOR]

A simple and inexpensive method for extraction of genomic DNA from mycelia of filamentous fungi was developed and the standardization of the protocol is described. The protocol includes both mycelium culturing and DNA extraction. By incorporating a selected commercial sand product into the culture media, the collection and the grinding of mycelia was simple and quick. The protocol of DNA extraction was derived from the alkaline lysis method for plasmid DNA extraction and modified to facilitate efficient extraction of fungal genomic DNA. It has increased efficiency and fidelity compared to the other simple DNA extraction protocols. Relative to a commonly used commercial DNA extraction kit, this extraction protocol is faster, easier and can generate more DNA without compromising quality. From a single sample of mycelium, genomic DNA can be prepared within 20 min, including concentration measurement. The DNA can be used in restriction enzyme digestion and as a template in PCR to amplify DNA fragments larger than 3000 base pairs. This method is recommended for DNA extraction in fungal phylogenetic studies when hundreds or thousands of isolates from one or a few closely-related species are subjected to PCR-based genotyping. [ABSTRACT FROM PUBLISHER]

Abstract: Canola seedling blight, caused by Rhizoctonia solani, and Fusarium spp., can result in large yield losses to canola (Brassica napus) at high inoculum pressure. The effect of inoculum density was studied by mixing different amounts of R. solani AG-2-1 and Fusarium avenaceum into a sterilized natural soil and soil-less mix (2:1, v:v) separately, and recording seedling emergence, damping-off and seedling height within ten days after seeding; root rot severity at 12 days after seeding and seed yield at harvest on canola cultivars ‘45H29’ and ‘73-77RR’. Root rot severity increased and emergence, plant height and seed yield decreased with increased inoculum density of both R. solani and F. avenaceum. For quantification of R. solani AG-2-1, a primer and TaqMan probe set (Rs21F/Rs21R/Rs21P) was designed based on the nuclear ribosomal internal transcribed spacer (ITS) region of R. solani AG-2-1. From a conventional PCR amplification, an 88-bp product was amplified from all isolates classified as AG-2-1 with the primers Rs21F and Rs21R. No product was amplified with DNA from isolates belonging to other anastomosis groups of R. solani, other pathogens or the host plant. By using quantitative PCR, DNA amounts as low as 100 fg of R. solani AG-2-1 were detected. The quantity of DNA from soil samples with different inoculum densities estimated using qPCR was highly correlated to the number of colony-forming units (cfu) obtained from the same soil samples for both R. solani AG-2-1 and F. avenaceum. [Copyright &y& Elsevier]