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Cercospora kikuchii (Tak. Matsumoto & Tomoy.) M.W. Gardner 1927 is an ascomycete fungal pathogen that causes Cercospora leaf blight and purple seed stain on soybean. Here, we report the first draft genome sequence and assembly of this pathogen. The C. kikuchii strain ARG_18_001 was isolated from soybean purple seed collected from San Pedro, Buenos Aires, Argentina, during the 2018 harvest. The genome was sequenced using a 2 × 150 bp paired-end method by Illumina NovaSeq 6000. The C. kikuchii protein-coding genes were predicted using FunGAP (Fungal Genome Annotation Pipeline). The draft genome assembly was 33.1 Mb in size with a GC-content of 53%. The gene prediction resulted in 14,856 gene models/14,721 protein coding genes. Genomic data of C. kikuchii presented here will be a useful resource for future studies of this pathosystem. The data can be accessed at GenBank under the accession number VTAY00000000 https://www.ncbi.nlm.nih.gov/nuccore/VTAY00000000.

Based on the precedent discovery of a weak antifungal indole isolated from Aporpium caryae, which increased its activity when changing the N-alkyl chain, nineteen N-alkyl

Late season diseases cause yield reductions to soybean grown worldwide. In Argentina, fungicide mixtures composed of quinone outside inhibitors (QoIs) and demethylation inhibitors (DMIs), and the newly introduced succinate dehydrogenase inhibitors (SDHIs), have been effective in managing these diseases. Nevertheless, the risk of selecting strains with resistance to these classes of fungicides is considered to be high. This preliminary study was carried out to determine in vitro sensitivities as determined by the effective concentration that inhibited 50% of radial mycelial growth (EC 50 values) of Cercospora kikuchii, Colletotrichum truncatum and Phomopsis phaseoli to selected QoI and DMI fungicide mixtures. The results indicated that EC 50 values ranged from 0.0065 to 0.0402 μg/ml for C. kikuchii, from 0.0344 to 0.1744 μg/ml for C. truncatum and from 0.0001 to 0.1974 μg/ml for P. phaseoli. To better study the possible resistance against these pathogens, future tests should consider several isolates for each pathogen from different production areas and different fungicide active ingredients.

Aspergillus flavus is the second-most common Aspergillus species isolated from human infection and the second leading cause of invasive and non-invasive aspergillosis in tropical countries, predominantly in Asia, the Middle East and Africa. 1 The treatment of aspergillosis typically involves a primary therapy with triazole antifungals. 2 Additionally, triazoles are an important group of successful fungicides used for more than 40 years to control fungal phytopathogens in agriculture owed to their effectiveness in a broad range of fungi. 3 These antifungals target fungal 14-α sterol demethylases (CYP51s), key enzymes in the biosynthetic

The increase in food production requires reduction of the damage caused by plant pathogens, minimizing the environmental impact of management practices. Soil‐borne pathogens are among the most relevant pathogens that affect soybean crop yield. Soybean sudden death syndrome (SDS), caused by several distinct species of Fusarium, produces significant yield losses in the leading soybean‐producing countries in North and South America. Current management strategies for SDS are scarce since there are no highly resistant cultivars and only a few fungicide seed treatments are available. Because of this, innovative approaches for SDS management need to be developed. Here, we summarize recently explored strategies based on plant nutrition, biological control, priming of plant defenses, host‐induced gene silencing, and the development of new SDS‐resistance cultivars using precision breeding techniques. Finally, sustainable management of SDS should also consider cultural control practices with minimal environmental impact. © 2021 Society of Chemical Industry.

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The aim of the present study was to evaluate indigenous PGPR (Plant growth promoting rhizobacteria) previously isolated from Argentina's soybean fields for their in vitro antagonistic effects on the control of Fusarium tucumaniae and F. virguliforme, in two separated in vitro assays. In assay 1, the bacteria that showed the highest significant (P < 0.05) F. tucumaniae mycelial growth inhibition were strains Bacillus subtilis 54 (70%), B. cereus 13 (44%), B. cereus 7 (44%) and Chryseobacterium vietnamense 110 (42%). Despite their antagonistic activity, the strains identified as Stenotrophomonas malthophilia and B. cereus were not included in any further experiments, because of their potential hazard. In assay 2, strains 54, 110 and Pseudomonas fluorescens 9 and 115 were tested against F. tucumaniae and F. virguliforme. In this study, native bacterial strains isolated from Argentine Pampas were tested for the first time against these pathogens. All four bacterial strains significantly inhibited mycelial growth of F. virguliforme. Further studies on the effects of these strains on the growth of soybean plants and on the Sudden Death Syndrome (SDS) control will uncover the mechanisms and in vitro antagonism potential of these bacterial isolates.