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Azole resistance in the fungal pathogen Aspergillus fumigatus is an emerging problem and may develop during azole therapy in humans and animals or exposure to azole fungicides in the environment. To assess the potential risk of azole-resistance emergence in avian farms where azole compounds are used for the control of avian mycoses, we conducted a drug susceptibility study including A. fumigatus isolates from birds and avian farms in France and Southern China. A total number of 175 isolates were analyzed: 57 isolates were collected in France in avian farms where chemoprophylaxis with parconazole was performed; 51 isolates were collected in southern China in avian farms where no chemoprophylaxis was performed; and 67 additional isolates came from the collection of a mycology laboratory. No resistant isolate was detected, and the distribution of minimum inhibitory concentrations was similar for isolates collected in farms with or without azole chemoprophylaxis. For 61 randomly selected isolates, the full coding sequence of the Cyp51A gene was determined to detect mutations. Nine amino acid alterations were found in the target enzyme, 3 of which were new.

Aspergillus flavus is second only to A. fumigatus in causing invasive aspergillosis and it is the major agent responsible for fungal sinusitis, keratitis and endophthalmitis in many countries in the Middle East, Africa and Southeast Asia. Despite the growing challenge due to A. flavus, data on the molecular epidemiology of this fungus remain scarce. The objective of the present study was to develop a new typing method based on the detection of VNTR (Variable number tandem repeat) markers. Eight VNTR markers located on 6 different chromosomes (1, 2, 3, 5, 7 and 8) of A. flavus were selected, combined by pairs for multiplex amplifications and tested on 30 unrelated isolates and six reference strains. The Simpson index for individual markers ranged from 0.398 to 0.818. A combined loci index calculated with all the markers yielded an index of 0.998. The MLVA (Multiple Locus VNTR Analysis) technique proved to be specific and reproducible. In a second time, a total of 55 isolates from Chinese avian farms and from a Tunisian hospital have been evaluated. One major cluster of genotypes could be defined by using the graphing algorithm termed Minimum Spanning Tree. This cluster comprised most of the isolates collected in an avian farm in southern China. The MLVA technique should be considered as an excellent and cost-effective typing method that could be used in many laboratories without the need for sophisticated equipment.

Hybrid breeding of tomatoes (Solanum lycopersicum), an important vegetable crop, is an effective way to improve yield and enhance disease and stress resistance. However, the efficiency of tomato hybridization is hindered by self-fertilization, which can be overcome using male sterile lines. It has been reported that reactive oxygen species (ROS) act as a key regulator for anther development, mediated by RBOH (Respiratory Burst Oxidase Homolog) genes. Here, two tomato anther-expressed genes, LeRBOH (Solyc01g099620) and LeRBOHE (Solyc07g042460), were selected to cultivate novel tomato male sterile strains. By using a CRISPR/Cas9 system with a two-sgRNA module, the lerboh, lerbohe, and lerboh lerbohe mutant lines were generated, among which the lerbohe and lerboh lerbohe mutants displayed complete male sterility but could accept wild-type pollens and produce fruits normally. Further analysis uncovered significantly decreased ROS levels and abnormal programmed cell death in lerboh lerbohe anthers, indicating a key role of ROS metabolism in tomato pollen development. Taken together, our work demonstrates a successful application of gene editing via CRISPR/Cas9 in generating male sterile tomatoes and afforded helpful information for understanding how RBOH genes regulating tomato reproduction process.

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