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Soil-borne diseases threaten sustainable agriculture, traditionally managed by chemical fumigants, whose use is now restricted due to environmental and health concerns. This study evaluates the biofumigation potential of Brassicaceae species, specifically Brassica carinata A. Braun., Brassica juncea (L.) Vassiliĭ Matveievitch Czernajew., Raphanus sativus L., and Sinapis alba L., cultivated in central Spain. Field trials across two growing cycles assessed biomass production, glucosinolate (GSL) concentration, photosynthetically active radiation (PAR) interception, and radiation use efficiency (RUE). Biomass production varied across species and sampling dates, with S. alba and R. sativus outperforming other species in shorter cycles, while B. juncea and B. carinata showed a more efficient GSL profile regarding soil-borne disease control, particularly in aliphatic GSLs like sinigrin. Results highlight B. juncea and B. carinata as potent biofumigants due to their high GSL levels, whereas S. alba and R. sativus are more suited to early biomass production. The study also explores the chlorophyll content index (SPAD) as a potential field indicator of GSL concentration, providing a practical approach for optimizing biofumigation timing. These findings support the selection of specific Brassicaceae species adapted to climatic conditions and crop cycles for effective biofumigation in sustainable agricultural practices. [ABSTRACT FROM AUTHOR]

Fusarium proliferatum is a globally distributed fungal pathogen that affects a range of crop hosts and is one of the main producers of mycotoxins, such as fumonisins, in foods. Specific PCR primers are commonly used for detection and identification of this pathogen. The aim of this study was to validate previously published F. proliferatum‐specific primers targeting the intergenic spacer (IGS) region and characterize intraspecific variation and homologous recombination events for isolates obtained from diseased garlic bulbs in Spain. Sixty‐nine isolates were morphologically identified as F. proliferatum, and their identity was confirmed by sequencing of the translation elongation factor; however, specific IGS primers did not result in an amplification product for nine of these isolates. Further analysis showed that this was due to polymorphism in the IGS region and six isolates were classified as IGS type I, while the remaining isolates were type II. Sequencing of the complete IGS region revealed numerous sequence polymorphisms amongst F. proliferatum isolates, and regions of recombination. Duplication and deletion events may have occurred via unequal crossing over during mitotic or meiotic recombination. These results suggest that the IGS region may be too variable as a reliable target for F. proliferatum‐specific identification. [ABSTRACT FROM AUTHOR]

This work examines the physiology of Schizosaccharomyces pombe (represented by strain 938) in the production of red wine, as the sole fermentative yeast, and in mixed and sequential fermentations with Saccharomyces cerevisiae 796. For further comparison, fermentations in which Saccharomyces cerevisiae was the sole fermentative yeast were also performed; in these fermentations a commercial lactic acid bacterium was used to perform malolactic fermentation once alcoholic fermentation was complete (unlike S. cerevisiae, the Sc. pombe performs maloalcoholic fermentation and therefore removes malic acid without such help). Relative density, acetic, malic and pyruvic acid concentrations, primary amino nitrogen and urea concentrations, and pH of the musts were measured over the entire fermentation period. In all fermentations in which Sc. pombe 938 was involved, nearly all the malic acid was consumed from an initial concentration of 5.5 g/L, and moderate acetic acid concentrations below 0.4 g/L were formed. The urea content of these wines was notably lower, showing a tenfold reduction when compared with those that were made with S. cerevisiae 796 alone. The sensorial properties of the different final wines varied widely. The wines fermented with Sc. pombe 938 had maximum aroma intensity and quality, and they were preferred by the tasters. [ABSTRACT FROM AUTHOR]

Spain is the second largest onion-producing country in Europe with 1,465,430 tons and an export value of 584 million € in 2021 (MAPA 2022). In summer 2022 rot bulb symptoms were observed in five commercial fields and during the storage of cultivars 'Orlenda', 'Veleta', 'Mallory', 'Citation' and 'Pantano' from La Roda in Albacete (Castilla-La Mancha, Spain). Approximately 20% of sampled bulbs (113 bulbs analyzed) were affected with dry scales showing brown to dark brown rot on the top and basal plate of the onion bulbs. Occasionally, white to light pink fungal mycelium was observed between rotten scales and the plate basal. Sections of dry scales (5-10 mm) of the apical and basal plate were cut and placed on potato dextrose agar (PDA) and Komada medium (Komada 1975). From 5-day-old cultures typical white to light pink mycelium with microconidia in chains formed on polyphialides and macroconidia resembling Fusarium proliferatum (Nelson et al. 1983). To confirm the pathogen identity, partial translation elongation factor 1-alpha ( TEF1 ) and RNA polymerase II subunit 2 ( RPB2 ) genes were amplified and sequenced using primers reported in O´Donnell et al. (1998) and Samuels et al. (2002) for TEF1 and Liu et al. (1999) for RPB2 . In BLAST analyses, the sequences showed 100% identity to the corresponding region of F. proliferatum (KP964908 and JF740801). Sequences were submitted to GenBank, and registered accession numbers are OR061014-16 for TEF1 and OR061017-19 for RPB2. Pathogenicity tests were conducted by inoculating healthy onion bulbs (five replicates per treatment) on the apical and basal plate by placing a 7-day old mycelial plug (10 mm diameter) from PDA cultures. Two onion cultivars ('Pandero' by Nunhems USA and 'Mallory' by Bejo The Netherlands) were inoculated separately with three isolates (PRO1, PRO9, PRO12). Control bulbs were inoculated with sterile PDA. The experiment was carried out twice. All bulbs were placed in a moist chamber and incubated at 25°C in the dark. After 15 days, bulbs inoculated with mycelial plugs showed similar symptoms to those of the original diseased bulbs. Browning dry rot was observed on the apical and basal plate of bulbs. When bulbs were cut longitudinally inner progressing rot was observed. Control bulbs remained symptomless. In both experiments, F. proliferatum was successfully re-isolated and morphologically confirmed from symptomatic bulbs to fulfill Koch's postulates. These results confirmed that isolates PRO1, PRO9 and PRO12 were the pathogen causing basal and dry rot on onion bulbs. This pathogen has recently been identified in China on Allium cepa L. var. agrogatum (Liu et al. 2022) and Idaho on onion (Beck et al. 2020) and could become a serious threat to onion production in Spain, reducing the quality and yield of onion.