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ABSTRACT Fire is a common ecological disturbance that structures terrestrial ecosystems and biological communities. The ability of fires to contribute to ecosystem heterogeneity has been termed pyrodiversity and has been directly linked to biodiversity (i.e., the pyrodiversity–biodiversity hypothesis). Since climate change models predict increases in fire frequency, understanding how fire pyrodiversity influences soil microbes is important for predicting how ecosystems will respond to fire regime changes. Here we tested how fire frequency‐driven changes in burn patterns (i.e., pyrodiversity) influenced soil microbial communities and diversity. We assessed pyrodiversity effects on soil microbes by manipulating fire frequency (annual vs. biennial fires) in a tallgrass prairie restoration and evaluating how changes in burn patterns influenced microbial communities (bacteria and fungi). Annual burns produced more heterogeneous burn patterns (higher pyrodiversity) that were linked to shifts in fungal and bacterial community composition. While fire frequency did not influence microbial (bacteria and fungi) alpha diversity, beta diversity did increase with pyrodiversity. Changes in fungal community composition were not linked to burn patterns, suggesting that pyrodiversity effects on other ecosystem components (e.g., plants and soil characteristics) influenced fungal community dynamics and the greater beta diversity observed in the annually burned plots. Shifts in bacterial community composition were linked to variation in higher severity burn pattern components (grey and white ash), suggesting that thermotolerance contributed to the observed changes in bacterial community composition and lower beta diversity in the biennially burned plots. This demonstrates that fire frequency‐driven increases in pyrodiversity augment biodiversity and may influence productivity in fire‐prone ecosystems. 

This work utilizes the collection of Raman spectra directly from thin layer chromatography (TLC) plates for quantitative determination of the pigment content of plant leaves. 

Sustainable food production is a grand challenge facing the global economy. Traditional agricultural practice requires numerous interventions, such as application of nutrients and pesticides, of which only a fraction are utilized by the target crop plants. Controlled release systems (CRSs) designed for agriculture could improve targeting of agrochemicals, reducing costs and improving environmental sustainability. CRSs have been extensively used in biomedical applications to generate spatiotemporal release patterns of targeted compounds. Such systems protect encapsulant molecules from the external environment and off-target uptake, increasing their biodistribution and pharmacokinetic profiles. Advanced ‘smart’ release designs enable on-demand release in response to environmental cues, and theranostic systems combine sensing and release for real-time monitoring of therapeutic interventions. This review examines the history of biomedical CRSs, highlighting opportunities to translate biomedical designs to agricultural applications. Common encapsulants and targets of agricultural CRSs are discussed, as well as additional demands of these systems, such as need for high volume, low cost, environmentally friendly materials and manufacturing processes. Existing agricultural CRSs are reviewed, and opportunities in emerging systems, such as nanoparticle, ‘smart’ release, and theranostic formulations are highlighted. This review is designed to provide a guide to researchers in the biomedical controlled release field for translating their knowledge to agricultural applications, and to provide a brief introduction of biomedical CRSs to experts in soil ecology, microbiology, horticulture, and crop sciences. 

The symbiotic interaction between plants and arbuscular mycorrhizal (AM) fungi is often perceived as beneficial for both partners, though a large ecological literature highlights the context dependency of this interaction. Changes in abiotic variables, such as nutrient availability, can drive the interaction along the mutualism-parasitism continuum with variable outcomes for plant growth and fitness. However, AM fungi can benefit plants in more ways than improved phosphorus nutrition and plant growth. For example, AM fungi can promote abiotic and biotic stress tolerance even when considered parasitic from a nutrient provision perspective. Other than being obligate biotrophs, very little is known about the benefits AM fungi gain from plants. In this review, we utilize both molecular biology and ecological approaches to expand our understanding of the plant–AM fungal interaction across disciplines. 

Beech leaf disease (BLD) is a recently discovered disease that is causing severe damage to American beech (Fagus grandifolia) in northeastern North America. The recently described nematode Litylenchus crenatae subsp. mccannii was detected in BLD-affected foliage and may be associated with the disease. However, speculation on the direct role of the nematode in infection still remains. In this study, we profiled the microbial communities associated with asymptomatic, symptomatic, and naïve (control) American beech foliage by using a high-throughput sequence-based metabarcoding analysis of fungi, bacteria, phytoplasmas, and nematodes. We then used both a differential abundance analysis and indicator species analysis as well as several diversity metrics to try and discover microbes associated only with symptomatic foliage. To do so, we amplified the organism-specific phylogenetic informative regions of the 16S, 18S, and internal transcribed spacer (ITS)1 regions using Illumina MiSeq. Our results detected the amplicon sequence variant (ASV) associated with the nematode L. crenatae subsp. mccannii but in all symptom types. However, four ASVs associated with the bacterial genera Wolbachia, Erwinia, Paenibacillus, and Pseudomonas and one ASV associated with the fungal genus Paraphaeosphaeria were detected only in symptomatic samples. In addition, we identified significant differences based on symptom type in both the α- and β-diversity indices for the bacterial and fungal communities. These results suggest that L. crenatae subsp. mccannii may not be fully responsible for BLD but, rather, that other microbes may be contributing to the syndrome, including the putative nematode endosymbiont Wolbachia sp.