A Pre-Landing Assessment of Regolith Properties at the InSight Landing Site

This article discusses relevant physical properties of the regolith at the Mars InSight landing site as understood prior to landing of the spacecraft. InSight will land in the northern lowland plains of Mars, close to the equator, where the regolith is estimated to be ≥3--5 m thick. These investigations of physical properties have relied on data collected from Mars orbital measurements, previously collected lander and rover data, results of studies of data and samples from Apollo lunar missions, laboratory measurements on regolith simulants, and theoretical studies. The investigations include changes in properties with depth and temperature. Mechanical properties investigated include density, grain-size distribution, cohesion, and angle of internal friction. Thermophysical properties include thermal inertia, surface emissivity and albedo, thermal conductivity and diffusivity, and specific heat. Regolith elastic properties not only include parameters that control seismic wave velocities in the immediate vicinity of the Insight lander but also coupling of the lander and other potential noise sources to the InSight broadband seismometer. The related properties include Poisson’s ratio, P- and S-wave velocities, Young’s modulus, and seismic attenuation. Finally, mass diffusivity was investigated to estimate gas movements in the regolith driven by atmospheric pressure changes. Physical properties presented here are all to some degree speculative. However, they form a basis for interpretation of the early data to be returned from the InSight mission.Additional co-authors: Nick Teanby and Sharon Keda

Direct effects of protective cladding material on insect pests in crops

Current horticultural crops are increasingly grown under protective plastic claddings. These have historically been used to protect crops from abiotic stresses, however new challenges are emerging that present opportunities for innovative control technologies. Protected cropping already provides a favourable environment for pest and disease establishment. Coupled with high labour costs, restrictions in pesticide approval and introductions of new invasive species, development of new pest and disease control methods is of paramount importance. Claddings have been formulated to change the properties of solar illumination in the crop environment with wide ranging implications for crop, pest and pathogen. Properties that interfere with pest behaviour, leading to disrupted host location and lower pest load, can be exploited as part of an Integrated Pest Management system. This review provides a state-of-the-art summary of the field and laboratory studies that have focused on the direct effects of UV-attenuating film claddings on insect pests. It relates this to insect vision and the likely mechanisms of pest control. Ultimately, it provides a useful synthesis of the research completed to date, and recommends future research and agronomy directions

Alimentary microbes of winter-form Drosophila suzukii

Drosophila suzukii (Matsumura) (Diptera: Drosophilidae) is a damaging pest of fruit. Reproductively diapausing adults overwinter in woodlands and remain active on warmer winter days. It is unknown if this adult phase of the lifecycle feeds during the winter period, and what the food source may be. This study characterized the flora in the digestive tract of D. suzukii using a metagenomics approach. Live D. suzukii were trapped in four woodlands in the south of England and their guts dissected for DNA extraction and amplicon-based metagenomics sequencing (internal transcribed spacer and 16S rRNA). Analysis at genus and family taxonomic levels showed high levels of diversity with no differences in digestive tract bacterial or fungal biota between woodland sites of winter-form D. suzukii. Female D. suzukii at one site appeared to have higher bacterial diversity in the alimentary canal than males, but there was a site, sex interaction. Many of the biota were associated with cold, wet climatic conditions and decomposition. This study provides the first evidence that winter-form D. suzukii may be opportunistic feeders during the winter period and are probably exploiting food sources associated with moisture on decomposing vegetation during this time. A core gut microbiome has been identified for winter-form D. suzukii

W638: Understanding and modifying the nutritional and oil quality architecture to breed Nutrition-Rich and high oil quality peanuts

Peanut or groundnut (Arachis hypogaea), grown and consumed in several Asian and African countries in addition to Americas, plays an important role in providing daily nutritional requirement for large population of the world. Aflatoxin contamination and allergens are the major quality and food safety concerns across globe which adversely impact the global peanut trade and commerce. On the other hand, high oleic acid is an industry preferred trait for imparting increased shelf life to peanut-based products. Through precise phenotyping, genomics, transcriptomics and molecular breeding approaches, we are developing better understanding of these traits, conducting trait mapping and candidate gene discovery, and deploying molecular breeding for developing improved peanut varieties. For example, transcriptome analysis have identified several important candidate genes and pathways for three different types of resistance mechanisms of aflatoxin contamination namely in vitro seed colonization (IVSC), pre-harvest aflatoxin contamination (PAC), and aflatoxin production (AP). Further, genetic analysis of multi-parent advanced generation intercross (MAGIC) and genome-wide association study (GWAS) on a diverse association mapping panel are likely to provide associated genomic regions and candidate genes for aflatoxin contamination. Development and deployment of precise ELISA-based methods for quantifying five major and important peanut allergens (Ara h 1, Ara h 2, Ara h 3, Ara h 6 and Ara h 8) have led to the identification of several hypoallergenic lines. Subsequently sequence/GWAS analysis is likely to identify the alleles responsible for making peanut, hypo or hyper allergenic. Allele-specific genetic markers were successfully deployed for developing several high oleic molecular breeding lines in multiple genetic backgrounds. Many of these lines are in final year of testing in India and are most likely to get released in 2019 for cultivation. Identification and development of improved peanut lines with combination of these nutritionally important and oil quality traits are likely to enhance the consumption and international trade of peanut

Tolerance of genetically characterized Folsomia candida strains to phenmedipham exposure

Abstract Background, Aims, and Scope The springtail Folsomia candida is a commonly used model species in ecotoxicological soil testing. The species reproduces parthenogenetically and, thus, laboratories use different clonal lineages. In this study, we investigated if genetic divergence between F. candida strains impacts the reaction to chemical stress and may thus affect the outcome of toxicity tests. Methods In two exposure assays (life-cycle reproduction test and avoidance behaviour test), three laboratory strains of F. candida from Portugal (PTG), Spain (SPN) and Denmark (DNK) were exposed to different concentrations of the reference chemical phenmedipham. Genetic divergence among strains was estimated based on mitochondrial COI sequence data. Results No significant differences between tolerance towards phenmedipham exposure were observed in a reproduction test. In contrast, one strain (SPN) showed a decreased susceptibility to phenmedipham compared to the other strains (PTG and DNK) in the avoidance assay. Discussion A phylogenetic tree based on mitochondrial COI sequences revealed clear genetic differentiation between both ‘reaction types’. Thus, we found a potential lineage dependent stress reaction in avoidance behaviour towards the pesticide. Conclusions Our findings have implications for the comparability of test results among laboratories. Reproduction tests seem to be more robust towards interclonal genetic differentiation than avoidance tests. Recommendations and Perspectives We recommend the use of molecular tools for simple and cost effective genetic characterization of F. candida strains used in chemical avoidance tests. Closer investigations concerning the relation between genetic relatedness and chemical response will provide a more detailed and comprehensive picture on the role of intraspecific genetic differentiation in stress tolerance

The phenotypic spectrum of Schaaf-Yang syndrome: 18 new affected individuals from 14 families

Genetics of disease, diagnosis and treatmen