Common Species Research Articles

Molecular and phenotypic identification of bacterial species isolated from cows with mastitis from three regions of Poland

BackgroundBovine mastitis is a widespread disease affecting dairy cattle worldwide and it generates substantial losses for dairy farmers. Mastitis may be caused by bacteria, fungi or algae. The most common species isolated from infected milk are, among others, Streptococcus spp., Escherichia coli, Staphylococcus aureus and non-aureus staphylococci and mammaliicocci. The aim of this paper is to determine the frequency of occurrence of bacterial species in milk samples from cows with mastitis from three regions of Poland: the north-east, the south-west and the south. To this end 203 milk samples taken from cows with a clinical form (CM) of mastitis (n = 100) and healthy animals (n = 103) were examined, which included culture on an appropriate medium followed by molecular detection of E. coli, S. aureus, Streptococcus agalactiae and Streptococcus uberis, as one of the most common species isolated from mastitis milk.ResultsThe results obtained indicated that S. uberis was the most commonly cultivated CM species (38%, n = 38), followed by S. aureus (22%, n = 22), E. coli (21%, n = 21) and S. agalactiae (18%, n = 18). Similar frequencies in molecular methods were obtained for S. uberis (35.1%) and S. aureus (28.0%). The variation of sensitivity of both methods may be responsible for the differences in the E. coli (41.0%, p = 0.002) and S. agalactiae (5.0%, p = 0.004) detection rates. Significant differences in composition of species between three regions of Poland were noted for E. coli incidence (p < 0.001), in both the culture and molecular methods, but data obtained by the PCR method indicated that this species was the least common in north-eastern Poland, while the culture method showed that in north-eastern Poland E. coli was the most common species. Significant differences for the molecular method were also observed for S. uberis (p < 0.001) and S. aureus (p < 0.001). Both species were most common in southern and south-western Poland.ConclusionsThe results obtained confirm the need to introduce rapid molecular tests for veterinary diagnostics, as well as providing important epidemiological data, to the best of our knowledge data on Polish cows in selected areas of Poland is lacking.

Personalideer: A comprehensive review of personality studies in cervids

Understanding animal personality, that is, consistent behavioural variation among individuals, is essential for elucidating the evolutionary origins of human personality. Despite extensive research on personality in diverse taxa, its significance in deer (i.e. cervids, family Cervidae), a taxon with diverse socioecological strategies, remains largely unexplored. This review summarizes the deer personality literature and highlights the knowledge gap in the studied species, personality assessment methods and traits, the general goal of the study, and implications for human personality research. We identified 32 eligible studies on seven species of deer, representing only a small portion of existing deer taxonomic diversity. More than half of the articles focused on three common deer species, roe deer ( Capreolus capreolus), fallow der ( Dama dama), and elk ( Cervus canadensis). Most studies evaluated reactions to capture, handling, and approaching humans, interpreting these behaviours as ‘Boldness’ or a ‘Coping style’. Also, most articles investigated the personality links to ecological variables, followed by physiological measures, and management applications. We advise researchers to move beyond measuring single traits and adopt a multitrait–multimethod approach, as is common in human personality research. Finally, deer and other animal models might be viable alternatives for studying adaptive value and genetic and environmental underpinnings of personality when research on humans is complicated.

The effects of turbulence on the growth of three different diatom species

The effects of turbulence on phytoplankton growth have received considerable attentions. However, the complexity of turbulence poses a significant challenge to its systematic characterization in the laboratory, resulting in relatively limited data on the effects of turbulence on several algal species. Here, a laboratory turbulence simulation system was set up to systematically investigate the growth of three common diatom species (Thalassiosira pseudonana, Skeletonema costatum, and Phaeodactylum tricornutum) under stationary and turbulent conditions (at 60, 120, 180 rpm), and measurements were taken for the algal biomass, algal photosynthetic activity, and nutrients consumption. By comparing the growth of three algae species under different turbulence exposure intensities, this study found that different algae exhibit varying sensitivities to turbulence, and therefore have different shear thresholds. Meanwhile, cell morphology is the key factor influencing the different shear threshold values observed in the three diatom species. Additionally, turbulence could impact algal aggregation and light availability, and dramatically improve nutrient uptake by phytoplankton. Our study will provides theoretical support for future endeavors in using turbulence to cultivate phytoplankton or combat algal blooms.

Rat lungworm, Cryptosporidium and other zoonotic pathogens of Rattus rattus and native wildlife on Sydney's Northern beaches

ABSTRACT Urbanisation is disrupting natural habitats and potentially causing spillover of zoonotic diseases from animals common in highly populated areas to natural environments and native wildlife. The black rat (Rattus rattus) is a common commensal species abundant in urban areas and nearby bushland in Australia and globally. It can be a major reservoir of pathogens and vectors for diseases that affect humans, pets, and wildlife. We examined pathogen prevalence in black rats and native wildlife in peri-urban northern Sydney. We trapped rats and native wildlife at eight 1-ha bushland sites and sampled for a range of internal pathogens from necropsied individuals (n=85 rats) and animal/trap swabs (n=54 native individuals). We detected a high prevalence of rat lungworm (Angiostrongylus spp.) in black rats (67%) as well as native wildlife including long-nosed bandicoots (Perameles nasuta; 43%; previously undetected) and bush rats (R. fuscipes; 33%). Incidence of detection tended to be more frequent where rat activity was greatest. Non-zoonotic Cryptosporidium spp. was also recorded in 17% of black rats and Salmonella spp. in 21% of bandicoots. Our findings suggest black rats may be facilitating spill-over of disease into native wildlife. The detected prevalence of Angiostrongylus spp. suggests an increasing occurrence in this natural system. These data provide valuable insight for disease management highlighting important reservoirs of disease which could be targeted to reduce disease burden in humans, pets, and wildlife.

Widespread establishment of adventive populations of Leptopilina japonica (Hymenoptera, Figitidae) in North America and development of a multiplex PCR assay to identify key parasitoids of Drosophila suzukii (Diptera, Drosophilidae)

In recent years, there has been an increase in the adventive establishment and spread of parasitoid wasps outside of their native range. However, lack of taxonomic tools can hinder the efficient screening of field-collected samples to document the establishment and range expansion of parasitoids on continent-wide geographic scales. Here we report that Leptopilina japonica (Hymenoptera, Figitidae), a parasitoid of the globally invasive fruit pest Drosophila suzukii (Diptera, Drosophilidae), is now widespread in much of North America despite not having been intentionally introduced. Surveys in 2022 using a variety of methods detected L. japonica in 10 of 11 surveyed USA States and one Canadian Province where it was not previously known to occur. In most surveys, L. japonica was the most common species of D. suzukii parasitoid found. The surveys also resulted in the detection of Ganaspis cf. brasiliensis (Hymenoptera, Figitidae), the recently-released biological control agent of D. suzukii, in six USA States where it had not previously been found. These new detections are likely a result of intentional biological control introductions rather than spread of adventive populations. A species-specific multiplex PCR assay was developed as a rapid, accurate and cost-effective method to distinguish L. japonica, G. cf. brasiliensis, the closely-related cosmopolitan parasitoid Leptopilina heterotoma (Hymenoptera, Figitidae) and other native parasitoid species. This dataset and the associated molecular tools will facilitate future studies of the spread and ecological impacts of these introduced parasitoids on multiple continents.

Taraxacum sect. Erythrosperma (Asteraceae, Cichorioideae) in Slovakia IV. Distribution of T. erythrospermum and synonymisation of T. slovacum

The group of lesser dandelions (Taraxacum sect. Erythrosperma) is represented by more than 215 species growing in mostly xerothermic habitats throughout Europe. The only known species with sexual reproduction in this section is the diploid T. erythrospermum. It occurs in southern parts of Europe and reaches its northern limit in central Europe. In this study, we aimed at a detailed mapping of the species distribution in Slovakia in order to understand the spatial distribution at its northern range limits. We found that it is the most common xerothermous species in Slovakia, growing on various substrates such as limestone, dolomite, travertine, volcanic rocks and sands, while it is less common on brown soils and ruderal biotopes. It is a characteristic species of the class Festuco-Brometea with an altitudinal range extending from 120 to 650 m above sea level. We delimited the northern distribution and documented its highest occurrence at approximately ca 1500 m a.s.l. Two taxa, T. slovacum and T. punctatum, were described from the territory of Slovakia and we discuss their relationships to T. erythrospermum, with which T. slovacum is synonymised here for the first time. We also present new data on the genome size of T. erythrospermum in Slovakia, which range from 1.529 to 1.604 pg with a mean of 1.554 pg (± 0.024 SD), and provide chorological data on a remarkable morphological variant with grey-coloured achenes.

Preemergence Herbicides and Mulches for Cutting Propagation—Impact on Rooting, Growth after Transplant, and Weed Control

Preemergence Herbicides and Mulches for Cutting Propagation—Impact on Rooting, Growth after Transplant, and Weed Control

Hibernacula of bats in Mexico, the southernmost records of hibernation in North America

Abstract Although Mexico holds the southernmost hibernating bats in North America, information on winter behavior and hibernacula microclimate use of temperate Mexican bats is limited. We studied hibernating bats at high altitudes (&amp;gt;1,000 m a.s.l.) in northern and central Mexico during 5 consecutive winters. Our aims were to document and describe the hibernacula, winter behavior (such as abundance and roost pattern), and microclimates (estimated as adjacent substrate temperature) of cave-hibernating bats in Mexico. We found 78 hibernacula and 6,089 torpid bats of 10 vespertilionid species, increasing by over 50% the number of cave-hibernating bat species and quadrupling the number of hibernacula for Mexico. Hibernacula were at altitudes between 1,049 and 3,633 m a.s.l., located in 3 mountain ranges, mainly in oak and conifer forests. Myotis velifer was the most common species, followed by Corynorhinus townsendii and C. mexicanus. We recorded the adjacent substrate temperatures from 9 species totaling 1,106 torpid bats and found differences in microclimate use among the 3 most common species. In general, abundance of torpid bats in our region of study was similar to those in the western United States, with aggregations of tens to a few hundred individuals per cave, and was lower than in the eastern United States where a cave may hold thousands of individuals. Knowledge of bat hibernation is crucial for developing conservation and management strategies on current conditions while accommodating environmental changes and other threats such as emerging diseases.

Complete mitochondrial genome sequence and phylogenetic analysis of Tylopilus brunneirubens (Boletales, Basidiomycota)

Tylopilus brunneirubens is a common species in southern China. It is known for brown to dark brown pileus, white context turning reddish brown or rust brown when touched and distinct reticulation on the upper stem. However, little is known about its mitochondrial genome and its relationship with other boletes. Our analysis revealed that the mitochondrial genome of this species is a circular DNA molecule that spans 32,389 bp. It contains 15 core protein-coding genes, 24 transfer RNA genes, and two ribosomal RNA genes. The base composition of the mitochondrial genome is as follows: A (37.20%), C (11.32%), G (12.48%), and T (39.00%), with a GC content of 23.80%. Furthermore, a phylogenetic tree based on 24 mitochondrial genomes provided valuable insights into the phylogenetic relationships of Tylopilus brunneirubens with other boletes for the first time.

Techniques for subretinal injections in animals.

Subretinal injections are not commonly performed during clinical treatment of animals but are frequently used in laboratory animal models to assess therapeutic efficacy and safety of gene and cell therapy products. Veterinary ophthalmologists are often employed to perform the injections in the laboratory animal setting, due to knowledge of comparative ocular anatomy between species and familiarity with operating on non-human eyes. Understanding the different approaches used for subretinal injection in each species and potential complications that may be encountered is vital to achieving successful and reproducible results. This manuscript provides a summary of different approaches to subretinal injections in the most common animal model species, along with information from published literature and experience of the authors to educate novice or experienced surgeons tasked with performing these injections for the first time.

Evaluation of single and mixed cover crops species in a sandy loam soil under corn production

AbstractInformed selection of cover crop species is critical for optimizing their benefits by considering the costs of adoption and potential initial negative impact on yields against the proven benefits for sustainable production. The Lower Mississippi Delta region is lagging in cover crop adoption, partly due to a paucity of this information from the area, despite being one of the major row crop‐producing regions in the United States. Common cover crop species in the region, cereal rye (CR) (Secale cereale), hairy vetch (HV) (Vicia villosa), and crimson clover (CC) (Trifolium incarnatum), and their possible two‐ and three‐combination mixes were evaluated for their impact on biomass production, enzyme activities, nutrient cycling, and corn (Zea mays) yields. HV + CC + CR and HV + CR produced the highest biomass and lowest yields compared to all treatments. HV and CC produced the least biomass but comparable yields to no cover crop. HV + CC + CR, HV + CR, CR, CC, and HV treatments had comparable total nitrogen, phosphorus, and soil organic carbon levels in the surface 0‐ to 5‐cm depth. Generally, CC alone and the HV + CR mix consistently displayed significantly higher phosphatase, N‐acetylglucosaminidase, β‐glucosidase, and cellobiohydrolase activities compared to all other treatments, while CR had the lowest. The single species of CC or HV may be the best option in the short term for initial cover crop implementation, rotating with CR a few years down the line for optimum long‐term benefits under corn production in this region.

[Fatal retroperitoneal necrotizing fasciitis due to Aeromonas caviae septicaemia].

Aeromonas is well-recognized for causing diarrhea and post-traumatic wound infections. The most common Aeromonas species include Aeromonas hydrophila, Aeromonas caviae, and Aeromonas sobria. In cases of immunocompromise and malignancy, Aeromonas infections can prove fatal. Instances of deadly necrotizing fasciitis in the extremities due to Aeromonas infection have been documented. Herein, acase of previously unreported fatal retroperitoneal necrotizing fasciitis involving Aeromonas caviae in apatient with ahistory of gastric cancer is presented.

Spatial distribution models for the four commercial tuna in the sea of maritime continent using multi-sensor remote sensing and maximum entropy

The dynamic of marine environmental parameters affects the distribution of commercial tuna in the sea of the maritime continent. Hence, the objectives of this study are to develop spatial distribution models for the four main tuna species in the Maritime continent's sea with reasonable accuracy, identify their correlation with marine environmental parameters, and investigate areas of interaction between those tuna species. The study develops the distribution models for albacore (Thunnus alalunga), bigeye (Thunnus obesus), yellowfin (Thunnus albacares), and skipjack (Katsuwonus pelamis) tuna species, utilizing multi-sensor satellite remote sensing and maximum entropy. The results show models have good performance, focusing on environmental factors such as sea surface temperature (SST), chlorophyll-a (CHL), and sea surface height anomalies (SSHA), combined with eddy kinetic energy (EKE). Seasonal variations in potential tuna habitats are revealed, emphasizing the influence of those marine environmental conditions. From December to May, the four commercial tuna species were distributed in conditions characterized by SST of 26–31.5 °C, CHL levels of 0–3 mg/l, SSHA of −0.3 to 0.2 m, and EKE of 0–1 m2/s2, while from June to November, they experienced SST of 23–31 °C, CHL levels of 0–4 mg/l, SSHA of −0.5 to 0.3 m, and EKE of 0–1.1 m2/s2. The spatial persistence of the four tuna species emerged mainly around the south sea of Java, with skipjack being the most common species found in the sea of the maritime continent. With sufficient and evenly distributed tuna presence records, the results indicate the potential for extrapolation beyond the training data to estimate habitat suitability for the four commercial tuna distributions. The results also suggest potential competition between tuna species sharing ecological niches and highlight possible overlapping areas where different tuna species interact with the same fishing gear.

Spatial variation in spring arrival patterns of Afro‐Palaearctic bird migration across Europe

AbstractAimGeographical patterns of migrant species arrival have been little studied, despite their relevance to global change responses. Here, we quantify continent‐wide interspecific variation in spatiotemporal patterns of spring arrival of 30 common migrant bird species and relate these to species characteristics and environmental conditions.LocationEurope.Time Period2010–2019.Major Taxa StudiedBirds, 30 species.MethodsUsing citizen science data from EuroBirdPortal, we modelled arrival phenology for 30 Afro‐Palaearctic migrant species across Europe to extract start and duration of species arrival at a 400 km square resolution. We related inter and intraspecific variation in arrival and duration to species characteristics and temperature at the start of the growing season (green‐up).ResultsSpatial variation in start of arrival times indicates that it took, on average, 1.6 days for the leading migratory front to move northwards by 100 km (range: 0.6–2.5 days). There was a major gradient in arrival phenology, from species which arrived earlier, least synchronously, in colder temperatures and progressed slowly northwards to species which arrived later, most synchronously and in warmer temperatures and advanced quickly through Europe. The slow progress of early arrivers suggests that temperature limits their northward advance; this group included Aerial Insectivores and species wintering north of the Sahel. For the late arrivers, which included species wintering further south, seasonal resource availability in Africa may delay their arrival into Europe.Main ConclusionsWe found support for the green‐wave hypothesis applying widely to migratory landbirds. Species arrival phenologies are linked to ecological differences between taxa, such as diet, and wintering location. Understanding these differences informs predictions of species' sensitivity to global change. Publishing these arrival phenologies will facilitate further research and have additional conservation benefits such as informing designation of hunting seasons. Our methods are applicable to any taxa with repeated occurrence data across large scales.

Environmental DNA storage and extraction method affects detectability for multiple aquatic invasive species

AbstractEnvironmental DNA (eDNA) refers to genetic material released by organisms into their surrounding environment. Collecting and identifying eDNA has gained popularity for monitoring and surveillance of aquatic invasive species. Invasive species management is most successful when an invasion is identified early while population size is likely to be low, highlighting the importance of eDNA detection sensitivity. Various factors influence DNA yield recovered from environmental samples. Environmental DNA storage and extraction methods, for example, can be adjusted to maximize DNA yield, thereby improving detectability. In this study, we compared the performance of two eDNA storage and extraction methods in detecting three common aquatic invasive species (Bythotrephes longimanus, Dreissena polymorpha, and Faxonius rusticus) across five natural ecosystems of Minnesota, United States. One method involved storing filters in 95% ethanol (EtOH) and extracting DNA using a DNeasy PowerSoil Pro Kit (Qiagen, Hilden, Germany), whereas the other method used cetyl trimethylammonium bromide (CTAB) for storage and a phenol–chloroform–isoamyl (PCI) procedure for DNA extraction. We also investigated the effect of DNA extract volume (1 μL relative to 3 μL) in qPCR reactions on eDNA detections for the commercial kit method. The CTAB‐PCI method yielded significantly more positive detections, across all three species, compared to the EtOH‐Qiagen method. Moreover, we found that using 1 μL of DNA extract in qPCR reactions was equally effective as using 3 μL. To improve detections of aquatic invasive species, we recommend that researchers store eDNA sample filters in CTAB or a similar lysis buffer such as Longmire's solution and extract with PCI when feasible, but note that lower extract volumes might be used without negative effect when either increasing technical replicates or repurposing samples for the detection of multiple species.

Macrozoobenthos Community Structure at Teluk Marunggai Beach, Nagari Sungai Nyalo, Pesisir Selatan District, West Sumatera Province

Teluk Marunggai Beach, Nagari Sungai Nyalo, is one of the new tourist areas in Pesisir Selatan Regency which, over time, will begin to be in demand by tourists, which will have an impact on the life of the biota on the beach, one of which is macrozoobenthos. This research was conducted in March 2023 in the Intertidal Zone of Teluk Marunggai Beach, Sungai Nyalo Village, Koto Ampek Tarusan District, Pesisir Selatan Regency, West Sumatra Province. The purpose of this study was to determine the type and abundance of macrozoobenthos species in the coastal waters of Marunggai Bay and to determine the diversity, uniformity, dominance and distribution patterns of macrozoobenthos in the coastal waters of Marunggai Bay. The research method used is the survey method, where the sampling using the quadrant transect method is carried out at three stations. The research results found 40 species of macrozoobenthos. The most common species found at all stations were Turbo cinereus from the Turbinidae family and the Gastropod class. The macrozoobenthos abundance values ​​obtained ranged from 6.44–6.67 ind/m2. Species diversity index values ​​ranged from 3.06–3.52, namely high. Uniformity index values ​​ranged from 3.02 to 3.14, high uniformity, dominance index values ​​ranged from 0.10 to 0.15; no species dominated, and the value of the distribution pattern ranged from 2.959 to 2.962 with a group distribution pattern

Characterizing BVOC emissions of common plant species in northern China using real world measurements: Towards strategic species selection to minimize ozone forming potential of urban greening

Biogenic volatile organic compounds (BVOCs) emitted by plants play a crucial role in ozone (O3) formation. Avoiding urban air quality trade-offs of urban greening involves selecting low-emission and O3 forming potential (OFP) plants. Using a dynamic enclosure system and the TD-GC-MS technique, we measured BVOC emissions from 47 common urban greening plant species in northern China. The potential to form O3 was estimated based on the emission quantification of 63 compounds and their maximum incremental reactivity (MIR) values. The results indicated that isoprene and most of monoterpene dominated BVOC emissions. Most of the broad-leaved trees were isoprene emitter, whereas needle-leaved and some broad-leaved trees emitted monoterpene and sesquiterpene. Alkene emissions, such as 1-hexene, were relatively low, while Phoebe zhennan exhibited higher aromatics such as m-ethyltoluene. Broad-leaved trees had a higher potential for O3 generation compared to needle-leaved trees. BVOC emission rates and OFP varied significantly among plant species, ranging from 0.08 to 112.23 μg/(g h) and 0.33–1130.75 μg/(g h), respectively. To minimize BVOC emissions and O3 pollution, we determined a list of preferred urban greening plants using hierarchical cluster analysis combined BVOC emission rates and OFPs. Based on our findings, we recommend incorporating plants with low BVOC emissions and OFPs, such as Eucommia ulmoides, Firmiana platanifolia, and Cercis chinensis, in future urban greening plans to prevent strengthening O3 pollution in northern China.

Assessing Knowledge of the Caracaras: Compiling Information, Identifying Knowledge Gaps, and Recommendations for Future Research

ABSTRACT Because information availability and management are essential components of wildlife conservation, we sought to compile literature published since 1900 on the caracaras, a group of nine extant species, eight of which occur only in Central America and South America. Our findings revealed that the number of sources and therefore, the amount and types of information available varied considerably among the caracara species and among countries where these raptors occur. Most sources represented studies conducted in Argentina, the United States, Brazil, and Chile, and many focused on the more common species, for example, the Crested Caracara (Caracara plancus) and the Chimango Caracara (Milvago chimango). Most sources published in the early 20th century focused on breeding and feeding ecology and natural history. Since the 1960s, the number of studies published per decade has increased, and since the 1990s, more studies have addressed a broader range of topics including behavioral ecology, demography, infectious agents, parasites, contaminants, biomedicine, and taxonomic relatedness among the caracara species and other falcons. Aside from the Striated Caracara (Phalcoboenus australis), which recently has been the subject of intensive research, other species in the genus Phalcoboenus (the Mountain Caracara [P. megalopterus]; the White-throated Caracara [P. albogularis]; and the Carunculated Caracara, [P. carunculatus]) remain little known, as do the two forest-dwelling caracaras, the Black Caracara (Daptrius ater) and the Red-throated Caracara (Ibycter americanus). Knowledge gaps exist for all the caracaras; research is especially needed on subjects outside typically studied topics such as breeding and feeding ecology. Also important to expanding knowledge of this group will be collaboration with researchers studying other avian scavengers such as condors and vultures, focusing on common threats, and coordination among researchers in countries inhabited by multiple caracara species.

Microbiological Profile of Culture-Positive Fungal Keratitis.

To examine the microbiological profile of cases of culture-positive fungal keratitis presenting to a tertiary eye care center in eastern India. Microbiology records of all culture-positive microbial keratitis patients presenting to L V Prasad Eye Institute, Bhubaneswar, between January 2020 and December 2021, were retrospectively reviewed. Collected data included smear results of culture-positive fungal or mixed infections, the species isolated, and the time taken for organisms to grow in each media. Fungal keratitis formed 36% of all culture-positive microbial keratitis, whereas mixed infections (fungi and other organisms) formed 8.5%. The most common fungal species isolated was Fusarium spp. (25.8%). The most common bacteria involved in mixed infection with fungi was Staphylococcus spp. (54.8%). The positivity of potassium hydroxide+calcofluor white stain in detecting fungal filaments was 89.0% and that of Gram stain was 76.1%. Culture-positive cases of fungal keratitis showed most frequent growth on potato-dextrose agar (77.6%). A similar pattern was observed in culture-positive mixed infections (Sabouraud dextrose agar [SDA]: 84%). Most frequent growth of bacteria in mixed infections was seen in thioglycolate broth (54.7%). The shortest time to achieve significant fungal growth was observed in blood agar (BA) and chocolate agar (CA) (2.2/2.3 days, and 1.8/2 days for fungal keratitis and mixed infections, respectively). Filamentous hyaline fungi took the shortest time to achieve significant growth (2.8 days), whereas yeast forms took the longest (5 days). This study highlights the importance of combined use of both solid and liquid culture media, especially potato dextrose agar (PDA)/SDA and CA, to arrive at a definitive diagnosis of fungal keratitis and possible bacterial co-infection, which forms a significant proportion of cases with fungal keratitis. In resource-poor laboratories, two culture media, either SDA or PDA, along with BA, may be plated to detect mixed infections. Examination of stained smears of corneal samples provides an inexpensive method of rapid diagnosis of fungal keratitis when culture media is not available.

Allometric relationships and trade-offs in 11 common Mediterranean-climate grasses.

Biomass allocation in plants is the foundation for understanding dynamics in ecosystem carbon balance, species competition, and plant-environment interactions. However, existing work on plant allometry has mainly focused on trees, with fewer studies having developed allometric equations for grasses. Grasses with different life histories can vary in their carbon investment by prioritizing the growth of specific organs to survive, outcompete co-occurring plants, and ensure population persistence. Further, because grasses are important fuels for wildfire, the lack of grass allocation data adds uncertainty to process-based models that relate plant physiology to wildfire dynamics. To fill this gap, we conducted a greenhouse experiment with 11 common California grasses varying in photosynthetic pathway and growth form. We measured plant sizes and harvested above- and belowground biomass throughout the life cycle of annual species, while for the establishment stage of perennial grasses to quantify allometric relationships for leaf, stem, and root biomass, as well as plant height and canopy area. We used basal diameter as a reference measure of plant size. Overall, basal diameter is the best predictor for leaf and stem biomass, height, and canopy area. Including height as another predictor can improve model accuracy in predicting leaf and stem biomass and canopy area. Fine root biomass is a function of leaf biomass alone. Species vary in their allometric relationships, with most variation occurring for plant height, canopy area, and stem biomass. We further explored potential trade-offs in biomass allocation across species between leaf and fine root, leaf and stem, and allocation to reproduction. Consistent with our expectation, we found that fast-growing plants allocated a greater fraction to reproduction. Additionally, plant height and specific leaf area negatively influenced the leaf-to-stem ratio. However, contrary to our hypothesis, there were no differences in root-to-leaf ratio between perennial and annual or C4 and C3 plants. Our study provides species-specific and functional-type-specific allometry equations for both above- and belowground organs of 11 common California grass species, enabling nondestructive biomass assessment in California grasslands. These allometric relationships and trade-offs in carbon allocation across species can improve ecosystem model predictions of grassland species interactions and environmental responses through differences in morphology.