Biology subjects

Kay, W. T.

Publications and source records attributed to Kay, W. T..

3 recordsLinked to original sources

bioRxiv2026

The scents of summer: Plant-diversity and vegetation-height drive health-relevant scent exposure in urban greenspaces

Urban green infrastructure is increasingly promoted as a public-health intervention, yet the biological features that determine exposure to potentially beneficial plant-derived volatile compounds remain poorly understood. Here we quantified airborne terpenes and terpenoids across five contrasting urban greenspaces in Oxford, UK, and related chemical profiles to plant diversity, vegetation structure and surrounding habitat characteristics. Ambient air samples collected across spring and summer were analysed by thermal-desorption gas chromatography-mass spectrometry, alongside field surveys of taxonomic richness, canopy cover, vegetation volume and ground composition. Terpene and terpenoid scentscapes differed strongly among sites and through time, with monoterpenes dominating detected profiles. Sites with greater plant richness and greater vegetation volume below 1.5 m consistently showed higher terpene/terpenoid abundance, whereas total vegetation volume, canopy cover and tree abundance were weaker and less consistent predictors. These relationships were specific to plant-associated chemical classes and were not observed for predominantly anthropogenic volatile compounds. These patterns were resolved across only five independent sampling sites, and the relationships reported here should therefore be considered exploratory. Our findings suggest that human exposure to plant-derived volatiles in cities may be maximised not simply by increasing tree cover, but by designing biodiverse, structurally complex lower-to-mid-storey vegetation within the breathing zone. These results provide an empirical basis for incorporating scentscape ecology into health-oriented urban greenspace design.

ecology↗

bioRxiv2025

Biocontrol against fungal mycoparasites driven by Bacillus velezensis strains from a mushroom crop microcosm

1.The cultivation of button mushroom (Agaricus bisporus) requires the design of tailor-made substrates that nourish the crop and promote morphology changes from mycelium to basidiome. The agronomic stages of mushroom development are also influenced by the microbiota present in the mushroom crop microcosm, which may have a beneficial impact on mushroom growth, development and quality, or a detrimental impact through reduction of yield or quality as parasites, competitors or disease vectors in mushroom crops. In this report we describe the isolation of multiple strains of Bacillus velezensis from mushroom casing material and basidiomes that show antifungal activity towards major mushroom mycoparasites, along with further characterization of their mode of action. Full genomes of B. velezensis CM5, CM19, CM35, EM5 and EM39 were sequenced and annotated, which together with metabolic profiling of specialised metabolites produced by CM5, CM19 and CM35 suggested that the antifungal activity of these strains is linked to the production of the lipopeptide fengycin. However, in crop trials, these strains did not increase mushroom yield or provide significant control of the mushroom parasite Lecanicillium fungicola. Genomic and analytical tools were designed and used to evaluate B. velezensis persistence in casing when the selected strains were artificially applied. B. velezensis population levels decreased significantly after application, potentially contributing to the lack of biocontrol activity observed in crop trials. 3. Key PointsO_LIB. velezensis strains isolated from peat-based microcosms are shown to have significant inhibitory effects against major fungal parasites of mushrooms in vitro. C_LIO_LIThrough full genome sequencing and metabolic profiling using LC-HRMS, the antifungal activity is correlated with the production of lipopeptides, particularly fengycin analogues. C_LIO_LIIn trials using button mushroom crops artificially infected with Lecanicillium fungicola, the causal agent of dry bubble, treatment of casing material with these strains did not significantly limit dry bubble disease or increase yield. C_LIO_LIThe persistence of strains in crop when artificially applied showed significant decreases after application on casing, potentially contributing to the lack of biocontrol activity. C_LI

microbiology↗

bioRxiv2024

Long-term survival of asexual Zymoseptoria tritici spores in the environment

The fungal phytopathogen Zymoseptoria tritici, causal agent of the economically damaging Septoria tritici blotch of wheat, is different from most foliar fungal pathogens in that its germination occurs slowly and apparently randomly after arrival on the leaf surface and is followed by a potentially prolonged period of epiphytic growth and even reproduction, during which no feeding structures are formed by the fungus. Thus, understanding the cues for germination and the mechanisms that underpin survival in low-nutrient environments could provide key new avenues for disease control. In this work, we examine survival, culturability, and virulence of spores following transfer from a high nutrient environment to water. We find that a sub-population of Z. tritici spores can survive and remain virulent for at least 7 weeks in water alone, during which time multicellular structures split to single cells. The fungus relies heavily on stored lipids; however, if cell suspensions in water are dried, the cells survive without lipid utilisation. Changes in gene expression in the first hours after suspension in water reflect adaptation to stress, while longer term starvation (7 days) induces changes particularly in primary metabolism and cytochrome P450 (CYP) gene expression. Importantly, we also found that Z. tritici spores are equally or better able to survive in soil as in water, and that rain-splash occurring 49 days after soil inoculation can transfer cells to wheat seedlings growing in inoculated soil and cause Septoria leaf blotch disease.

microbiology↗