Mycorrhizal Species Differentially Alter Plant Growth and Response to Herbivory

Plants simultaneously interact with multiple organisms which can both positively and negatively affect their growth. Herbivores can reduce plant growth through loss of plant biomass and photosynthetic area, while plant mutualists, such as mycorrhizal fungi, can increase plant growth through uptake of essential nutrients. This is the first study examining whether species-specific associations with mycorrhizal fungi alter plant tolerance to herbivory. We grew Plantago lanceolata plants with three species of mycorrhizal fungi previously shown to have differential impacts on plant growth and subjected them to herbivory by the specialist lepidopteran herbivore, Junonia coenia. Association with mycorrhizal fungus Glomus white provided the greatest growth benefit but did not alter plant response to herbivory. Alternatively, association with Archaeospora trappei provided less growth promotion but did lead to tolerance to herbivory in the form of an increased growth rate. Finally, an association with the fungus Scutellospora calospora led to neither plant growth promotion nor tolerance to herbivory. In fact, an association with S. calospora appeared to reduce plant tolerance to herbivory. An association with all three species of mycorrhizae resulted in a pattern of growth similar to that of plants grown only with Glomus white, suggesting that growth promotion by multiple mycorrhizal species is driven by the inclusion of a “super fungus,” in this case, Glomus white. This work illustrates that plant response to herbivory depends upon the mycorrhizal fungal mutualist with which a plant is associated

Beyond the black box: promoting mathematical collaborations for elucidating interactions in soil ecology

Understanding soil systems is critical because they form the structural and nutritional foundation for plants and thus every terrestrial habitat and agricultural system. In this paper, we encourage increased use of mathematical models to drive forward understanding of interactions in soil ecological systems. We discuss several distinctive features of soil ecosystems and empirical studies of them. We explore some perceptions that have previously deterred more extensive use of models in soil ecology and some advances that have already been made using models to elucidate soil ecological interactions. We provide examples where mathematical models have been used to test the plausibility of hypothesized mechanisms, to explore systems where experimental manipulations are currently impossible, or to determine the most important variables to measure in experimental and natural systems. To aid in the development of theory in this field, we present a table describing major soil ecology topics, the theory previously used, and providing key terms for theoretical approaches that could potentially address them. We then provide examples from the table that may either contribute to important incremental developments in soil science or potentially revolutionize our understanding of plant–soil systems. We challenge scientists and mathematicians to push theoretical explorations in soil systems further and highlight three major areas for the development of mathematical models in soil ecology: theory spanning scales and ecological hierarchies, processes, and evolution

Three-Way Interactions among Mutualistic Mycorrhizal Fungi, Plants, and Plant Enemies: Hypotheses and Synthesis

A number of studies have shown that an association with mycorrhizal fungi can alter the outcome of interactions between plants and their enemies. While the directions of these effects vary, their strength suggests the need for greater attention to multispecies interactions among plant enemies, plants, and mycorrhizal fungi. We recognize that mycorrhizal fungi could effect plant enemies by improving plant nutrition, modifying plant tolerance, or modifying plant defenses. In addition, mycorrhizal fungi could directly interfere with pathogen infection, herbivory, or parasitism by occupying root space. We formalize these alternative outcomes of multispecies interactions and explore the long‐term dynamics of the plant‐enemy interactions based on these different scenarios using a general model of interactions between plants and plant enemies. We then review the literature in terms of the assumptions of the alternative mechanisms and the predictions of these models. Through this effort, we identify new directions in the study of tritrophic interactions between enemies, plants, and soil mutualists

The Effect of Ethnicity on Neuropsychological Test Performance of Former NFL Athletes

Objective: To investigate the effect of ethnicity on neuropsychological test performance by specifically exploring differences between white and black former NFL athletes on subtests of the WAIS-IV. Participants and Methods: Data was derived from a de-identified database in Florida consisting of 63 former NFL athletes (Mage=50.38; SD=11.57); 28 white and 35 black. Participants completed the following subtests of the WAIS-IV: Block Design, Similarities, Digit Span, Matrix Reasoning, Arithmetic, Symbol Search, Visual Puzzles, Coding, and Cancellation. Results: One-Way ANOVA yielded a significant effect between ethnicity and performance on several subtests. Black athletes had significantly lower scaled scores than white athletes on Block Design F(1,61)=14.266, p\u3c.001, Similarities F(1,61)=5.904, p=.018, Digit Span F(1,61)=8.985, p=.004, Arithmetic F(1,61)=16.07, p\u3c.001 and Visual Puzzles F(1,61)=16.682, p\u3c .001. No effect of ethnicity was seen on performance of Matrix Reasoning F(1,61)=2.937, p=.092, Symbol Search F(1,61)=3.619, p=.062, Coding F(1,61)=3.032, p=.087 or Cancellation F(1,61)=2.289, p=.136. Conclusions: Results reveal significant differences between white and black athletes on all subtests of the WAIS-IV but those from the Processing Speed Scale and Matrix Reasoning. These findings align with previous literature that found white individuals to outperform African-Americans on verbal and non-verbal tasks after controlling for socioeconomic and demographic variables (Manly & Jacobs, 2002). These differences may also be a reflection of the WAIS-IV’s psychometric properties and it is significant to consider the normative sample used may not be appropriate for African-Americans. This study highlights the need for future research to identify how ethnicity specifically influences performance, sheds light on the importance of considering cultural factors when interpreting test results, and serves as a call to action to further understand how and why minorities may not be accurately represented in neuropsychological testing

Bacterial disease induced changes in fungal communities of olive tree twigs depend on host genotype

In nature, pathogens live and interact with other microorganisms on plant tissues. Yet, the research area exploring interactions between bacteria-fungi and microbiota-plants, within the context of a pathobiome, is still scarce. In this study, the impact of olive knot (OK) disease caused by the bacteria Pseudomonas savastanoi pv. savastanoi (Psv) on the epiphytic and endophytic fungal communities of olive tree twigs from three different cultivars, was investigated in field conditions. The ITS-DNA sequencing of cultivable fungi, showed that OK disease disturbs the resident fungal communities, which may reflect changes in the habitat caused by Psv. In particular, a reduction on epiphyte abundance and diversity, and changes on their composition were observed. Compared to epiphytes, endophytes were less sensitive to OK, but their abundance, in particular of potential pathogens, was increased in plants with OK disease. Host genotype, at cultivar level, contributed to plant fungal assembly particularly upon disease establishment. Therefore, besides fungi - Psv interactions, the combination of cultivar - Psv also appeared to be critical for the composition of fungal communities in olive knots. Specific fungal OTUs were associated to the presence and absence of disease, and their role in the promotion or suppression of OK disease should be studied in the future.This research was partially supported by FEDER funds through COMPETE (Programa Operacional Factores de Competitividade) and by national funds through FCT (Fundacao para a Ciencia e a Tecnologia) in the framework of the project EXCL/AGR-PRO/0591/2012. This work was supported by FCT under the project UID/MULTI/04046/2013. T. Gomes thanks FCT, POPH-QREN and FSE for PhD SFRH/BD/98127/2013 grant; and also the COST Action FA1405 for a short-term scientific mission (STSM) grant

Differential Binding of Co(II) and Zn(II) to Metallo-β-Lactamase Bla2 from \u3cem\u3eBacillus anthracis\u3c/em\u3e

In an effort to probe the structure, mechanism, and biochemical properties of metallo-β-lactamase Bla2 from Bacillus anthracis, the enzyme was overexpressed, purified, and characterized. Metal analyses demonstrated that recombinant Bla2 tightly binds 1 equiv of Zn(II). Steady-state kinetic studies showed that mono-Zn(II) Bla2 (1Zn-Bla2) is active, while di-Zn(II) Bla2 (ZnZn-Bla2) was unstable. Catalytically, 1Zn-Bla2 behaves like the related enzymes CcrA and L1. In contrast, di-Co(II) Bla2 (CoCo-Bla2) is substantially more active than the mono-Co(II) analogue. Rapid kinetics and UV−vis, 1H NMR, EPR, and EXAFS spectroscopic studies show that Co(II) binding to Bla2 is distributed, while EXAFS shows that Zn(II) binding is sequential. To our knowledge, this is the first documented example of a Zn enzyme that binds Co(II) and Zn(II) via distinct mechanisms, underscoring the need to demonstrate transferability when extrapolating results on Co(II)-substituted proteins to the native Zn(II)-containing forms

Beyond the black box: promoting mathematical collaborations for elucidating interactions in soil ecology

Understanding soil systems is critical because they form the structural and nutritional foundation for plants and thus every terrestrial habitat and agricultural system. In this paper, we encourage increased use of mathematical models to drive forward understanding of interactions in soil ecological systems. We discuss several distinctive features of soil ecosystems and empirical studies of them. We explore some perceptions that have previously deterred more extensive use of models in soil ecology and some advances that have already been made using models to elucidate soil ecological interactions. We provide examples where mathematical models have been used to test the plausibility of hypothesized mechanisms, to explore systems where experimental manipulations are currently impossible, or to determine the most important variables to measure in experimental and natural systems. To aid in the development of theory in this field, we present a table describing major soil ecology topics, the theory previously used, and providing key terms for theoretical approaches that could potentially address them. We then provide examples from the table that may either contribute to important incremental developments in soil science or potentially revolutionize our understanding of plant–soil systems. We challenge scientists and mathematicians to push theoretical explorations in soil systems further and highlight three major areas for the development of mathematical models in soil ecology: theory spanning scales and ecological hierarchies, processes, and evolution

Effect of host plant and olive Ieaf spot disease on fungal community assembly in olive tree phyllosphere

Olive leaf spot (OLS), a disease that usually occurs on the upper surface of the olive leaf, is caused by the fungus Fusicladium oleagineum with an ability to grow epiphytically and to enter inner leaf tissues. ln this work was studied the effect that host plant, at different levels (i.e. at cultivar level, in resistance to the fungal pathogen, and F. oleogineum infection), have on the phyllosphere fungal community composition of olive tree. For this, both epiphytic and endophytic fungal community inhabiting OLS-symptomatic and asymptomatic leaves of three co-occurring cultivars with different susceptibilities to OLS were compared, after isolation and identification of species by ITS rDNA sequencing. The results indicate that the presence of OLS on leaves had a major effect on the fungal community composition than the host plant, either at cultivar level or of their resistance to the fungal pathogen. Both diversity and abundance of epiphytes in asymptomatic leaves were significantly higher (up to 2.O-fold) than in symptomatic leaves, Although less pronounced, this trend was also evident in endophytes of two of the cultivars surveyed. Among the species identified in asymptomatic leaf, Cladosporium clodosporÍoides and Chromelosporium carneum were the most frequently isolated within epiphytic and endophytic fungal communities, respectively; whereas in symptomatic leaf, Cladosporium sp, and Pseudocercosporo cladosporioides, were the most frequently isolated within epiphytic and endophytic fungal communities, respectively. Determination of indicator value indices has shown significant preference/specificity of four species with asymptomatic leaves, and of two species with symptomatic leaves. Based on this analysis both Atternorio sp. and Tricharina striisporo seems to be the species with the most potential for OLS disease suppression. Future research needs to decipher these complex and dynamic interaction networks and assess their role in plant health.info:eu-repo/semantics/publishedVersio

Feasibility of low-intensity psychological interventions for emotional and behavioural difficulties in children and young people with genetic conditions: a case series

Background: Children with genetic conditions may experience significant mental health difficulties such as anxiety and challenging behaviour. However, understanding of the feasibility and effectiveness of psychological interventions for emotional and behavioural problems in the context of genetic conditions is limited. Low-intensity psychological interventions have demonstrated promise in paediatric populations and may be able to address their mental health difficulties. / Method: A case series design was used to assess the feasibility of low-intensity interventions for emotional and behavioural difficulties in children and young people with genetic conditions recruited from a mental health drop-in centre at a tertiary hospital. Participants received seven weekly sessions with a trained practitioner. The intervention was based on existing modular treatments and evidence-based self-help materials. Feasibility and treatment satisfaction were assessed, as well as measures of symptoms of anxiety and challenging behaviour, treatment goals, and quality of life, at baseline, during treatment, and six-month follow-up. / Results: Five participants received treatment for challenging behaviour, one for anxiety, and one for obsessive compulsive disorder. All participants completed treatment. Clinically significant change in the SDQ Total score was found in three participants. All participants demonstrated progress in goals and symptoms of emotional and behavioural difficulties over the course of treatment. / Conclusions: Low-intensity psychological interventions for emotional and behavioural difficulties in children and young people with genetic conditions is feasible, acceptable, and potentially beneficial. Further research is warranted to examine the effectiveness of the intervention and its use in clinical paediatric settings