Ecophysiological Crop Modelling Combined with Genetic Analysis Is a Powerful Tool for Ideotype Design

Improving the grain yield of crops in both favourable and stressful environments is the main breeding objective required to ensure food security. In this review, I outline a genotype-to-phenotype approach that exploits the potential values of quantitative genetics and process-based crop modelling in developing new plant types with high yields. The effects of quantitative trait locus (QTL), for traits typically at the single-organ level over a short time scale, were projected for their impact on crop growth during the whole growing season in the field. This approach can provide more markers for selection programmes for specific environments whilst also allowing for prioritization. Crop modelling is thus a powerful tool for ideotyping under contrasting conditions, i.e., use of single-environment information for predicting phenotypes under different environments.

Calcium/Calmodulin-Mediated Defense Signaling: What Is Looming on the Horizon for AtSR1/CAMTA3-Mediated Signaling in Plant Immunity

Calcium (Ca2+) signaling in plant cells is an essential and early event during plant-microbe interactions. The recognition of microbe-derived molecules activates Ca2+ channels or Ca2+ pumps that trigger a transient increase in Ca2+ in the cytoplasm. The Ca2+ binding proteins (such as CBL, CPK, CaM, and CML), known as Ca2+ sensors, relay the Ca2+ signal into down-stream signaling events, e.g., activating transcription factors in the nucleus. For example, CaM and CML decode the Ca2+ signals to the CaM/CML-binding protein, especially CaM-binding transcription factors (AtSRs/CAMTAs), to induce the expressions of immune-related genes. In this review, we discuss the recent breakthroughs in down-stream Ca2+ signaling as a dynamic process, subjected to continuous variation and gradual change. AtSR1/CAMTA3 is a CaM-mediated transcription factor that represses plant immunity in non-stressful environments. Stress-triggered Ca2+ spikes impact the Ca2+-CaM-AtSR1 complex to control plant immune response. We also discuss other regulatory mechanisms in which Ca2+ signaling activates CPKs and MAPKs cascades followed by regulating the function of AtSR1 by changing its stability, phosphorylation status, and subcellular localization during plant defense.

Host defense mechanisms induce genome instability leading to rapid evolution in an opportunistic fungal pathogen

The ability to generate genetic variation facilitates rapid adaptation in stressful environments. The opportunistic fungal pathogen Candida albicans frequently undergoes large-scale genomic changes, including aneuploidy and loss-of heterozygosity (LOH), following exposure to host environments. However, the specific host factors inducing C. albicans genome instability remain largely unknown. Here, we leveraged the genetic tractability of nematode hosts to investigate whether innate immune components, including antimicrobial peptides (AMPs) and reactive oxygen species (ROS), induced host-associated C. albicans genome instability. C. albicans associated with immunocompetent hosts carried multiple large-scale genomic changes including LOH, whole chromosome, and segmental aneuploidies. In contrast, C. albicans associated with immunocompromised hosts deficient in AMPs or ROS production had reduced LOH frequencies and fewer, if any, additional genomic changes. To evaluate if extensive host-induced genomic changes had long-term consequences for C. albicans adaptation, we experimentally evolved C. albicans in either immunocompetent or immunocompromised hosts and selected for increased virulence. C. albicans evolved in immunocompetent hosts rapidly increased virulence, but not in immunocompromised hosts. Taken together, this work suggests that host-produced ROS and AMPs induces genotypic plasticity in C. albicans which facilitates rapid evolution.

Mnemonic Oasis: Interior architecture as a stimulus for wellbeing through sensorial experience

<p>In today’s society the priority of work and careers has resulted in highly stressful environments. In the twenty-first century the tendency of inflated urban centres has encouraged people to move to the cities and as the urban population increases, the quality of life, people’s wellbeing and overall life satisfaction, becomes a concern. Interested in the effect of human perception through spatial design, this thesis explores how sensorial experience can influence the design of interior architecture to promote productivity and wellbeing. This research aims to explore the implications of environmental stimuli and sensory experience to enhance an occupant’s behaviour and wellbeing within an interior space. Looking closely at the built environment that we inhabit and identifying how it impacts its occupants would aid in how we as designers could design spaces that benefit the occupant’s quality of life. This thesis asks how interior architecture may be utilised to enhance the sense of productivity, wellbeing and life satisfaction of the working class and city dwellers. In addition, this thesis aims to adaptively reuse a historic site in the Wellington CBD as the principal vehicle for the design component of this study. Overall the research suggests providing multiple opportunities for occupants to engage with the built and natural environment whereby interior architecture, through atmospheres and sensorial experiences, contributes to the solution in establishing a sense of productivity, wellbeing and life satisfaction.</p>

Germ cell apoptosis is critical to maintain Caenorhabditis elegans offspring viability in stressful environments

Maintaining reproduction in highly variable, often stressful, environments is an essential challenge for all organisms. Even transient exposure to mild environmental stress may directly damage germ cells or simply tax the physiology of an individual, making it difficult to produce quality gametes. In Caenorhabditis elegans, a large fraction of germ cells acts as nurse cells, supporting developing oocytes before eventually undergoing so-called physiological germ cell apoptosis. Although C. elegans apoptosis has been extensively studied, little is known about how germline apoptosis is influenced by ecologically relevant environmental stress. Moreover, it remains unclear to what extent germline apoptosis contributes to maintaining oocyte quality, and thus offspring viability, in such conditions. Here we show that exposure to diverse environmental stressors, likely occurring in the natural C. elegans habitat (starvation, ethanol, acid, and mild oxidative stress), increases germline apoptosis, consistent with previous reports on stress-induced apoptosis. Using loss-of-function mutant alleles of ced-3 and ced-4, we demonstrate that eliminating the core apoptotic machinery strongly reduces embryonic survival when mothers are exposed to such environmental stressors during early adult life. In contrast, mutations in ced-9 and egl-1 that primarily block apoptosis in the soma but not in the germline, did not exhibit such reduced embryonic survival under environmental stress. Therefore, C. elegans germ cell apoptosis plays an essential role in maintaining offspring fitness in adverse environments. Finally, we show that ced-3 and ced-4 mutants exhibit concomitant decreases in embryo size and changes in embryo shape when mothers are exposed to environmental stress. These observations may indicate inadequate oocyte provisioning due to the absence of germ cell apoptosis. Taken together, our results show that the central genes of the apoptosis pathway play a key role in maintaining gamete quality, and thus offspring fitness, under ecologically relevant environmental conditions.

Mnemonic Oasis: Interior architecture as a stimulus for wellbeing through sensorial experience

<p>In today’s society the priority of work and careers has resulted in highly stressful environments. In the twenty-first century the tendency of inflated urban centres has encouraged people to move to the cities and as the urban population increases, the quality of life, people’s wellbeing and overall life satisfaction, becomes a concern. Interested in the effect of human perception through spatial design, this thesis explores how sensorial experience can influence the design of interior architecture to promote productivity and wellbeing. This research aims to explore the implications of environmental stimuli and sensory experience to enhance an occupant’s behaviour and wellbeing within an interior space. Looking closely at the built environment that we inhabit and identifying how it impacts its occupants would aid in how we as designers could design spaces that benefit the occupant’s quality of life. This thesis asks how interior architecture may be utilised to enhance the sense of productivity, wellbeing and life satisfaction of the working class and city dwellers. In addition, this thesis aims to adaptively reuse a historic site in the Wellington CBD as the principal vehicle for the design component of this study. Overall the research suggests providing multiple opportunities for occupants to engage with the built and natural environment whereby interior architecture, through atmospheres and sensorial experiences, contributes to the solution in establishing a sense of productivity, wellbeing and life satisfaction.</p>

Secondary phloem traits in mature stems of Betula ermanii in stressful environments of volcanic activity

This research summarizes the results of study of structural peculiarities of Betula ermanii growing around Baransky Volcano close to the thermal Golubye Ozera. We have performed statistical analysis of parameters of the secondary phloem of multiyear shoots and stems and found some features tied to extreme environmental conditions. We have found that structural reaction of the secondary phloem of multiyear shoots and stems of B. ermanii to the extreme conditions of post-volcanic activity of Baransky Volcano manifests itself as changes in the geometry of the conductive elements and dilatation of the radial parenchyma in the non-conductive phloem. We believe these changes to be adaptive in nature due to the need for increased conductivity in volcanic landscapes.

Oxidative Stress, Mitochondrial Function and Adaptation to Exercise: New Perspectives in Nutrition

Cells have the ability to adapt to stressful environments as a part of their evolution. Physical exercise induces an increase of a demand for energy that must be met by mitochondria as the main (ATP) provider. However, this process leads to the increase of free radicals and the so-called reactive oxygen species (ROS), which are necessary for the maintenance of cell signaling and homeostasis. In addition, mitochondrial biogenesis is influenced by exercise in continuous crosstalk between the mitochondria and the nuclear genome. Excessive workloads may induce severe mitochondrial stress, resulting in oxidative damage. In this regard, the objective of this work was to provide a general overview of the molecular mechanisms involved in mitochondrial adaptation during exercise and to understand if some nutrients such as antioxidants may be implicated in blunt adaptation and/or an impact on the performance of exercise by different means.

The importance of intraspecific diversity on duckweed growth with and without salt stress

The pollution of freshwater ecosystems is threatening freshwater plant species diversity worldwide. Freshwater plants, such as duckweed (Lemna minor), are potentially sensitive to novel stressful environments. To test if intraspecific diversity could increase resistance to stressful environments, I used seven L. minor populations and assessed their growth rates in the absence and presence of moderate salt stress across an intraspecific diversity gradient.I grew the populations (ecotypes) of L. minor over five months in 92 experimental mesocosms in a glasshouse either in ecotype monocultures or in polyculture with either one or three conspecific ecotypes (23 unique compositions). The experiment was conducted in semi-natural conditions, including a natural community of algae and microbes. After assessing the duckweed growth rate in unperturbed conditions, the cultures were subjected to moderate salt stress (50mM NaCl) for several weeks. Population abundances were assessed weekly, both on the ecotype level and the whole-population level.Throughout the experiment, the ecotypes differed in their growth rates, the fastest growing at twice the rate of others. Whether the ecotypes grew in monoculture or in polyculture with other conspecifics further shaped the ecotype growth rates. Ecotype polycultures showed higher abundances towards the end of the experiment, indicating that over time, as the environment deteriorated, intraspecific diversity gained in importance. These findings show that intraspecific variation in growth rates can translate to a positive effect of intraspecific diversity on whole-population abundance. Exposure of L. minor to moderate salt levels did not significantly impact growth rates.