Summary Plants are exposed to combinations of various biotic and abiotic stresses, but stress responses are usually investigated for single stresses only.Here, we investigated the genetic architecture underlying plant responses to 11 single stresses and several of their combinations by phenotyping 350 Arabidopsis thaliana accessions. A set of 214 000 single nucleotide polymorphisms (SNPs) was screened for marker‐trait associations in genome‐wide association (GWA) analyses using tailored multi‐trait mixed models.Stress responses that share phytohormonal signaling pathways also share genetic architecture underlying these responses. After removing the effects of general robustness, for the 30 most significant SNPs, average quantitative trait locus (QTL) effect sizes were larger for dual stresses than for single stresses.Plants appear to deploy broad‐spectrum defensive mechanisms influencing multiple traits in response to combined stresses. Association analyses identified QTLs with contrasting and with similar responses to biotic vs abiotic stresses, and below‐ground vs above‐ground stresses. Our approach allowed for an unprecedented comprehensive genetic analysis of how plants deal with a wide spectrum of stress conditions.

The type III secretion system (T3SS) is an important genetic determinant that mediates interactions between Gram-negative bacteria and their eukaryotic hosts. Our understanding of the T3SS continues to expand, yet the availability of new bacterial genomes prompts questions about its diversity, distribution and evolution. Through a comprehensive survey of ∼20 000 bacterial genomes, we identified 174 non-redundant T3SSs from 109 genera and 5 phyla. Many of the bacteria are environmental strains that have not been reported to interact with eukaryotic hosts, while several species groups carry multiple T3SSs. Four ultra-conserved Microsynteny Blocks (MSBs) were defined within the T3SSs, facilitating comprehensive clustering of the T3SSs into 13 major categories, and establishing the largest diversity of T3SSs to date. We subsequently extended our search to identify type III effectors, resulting in 8740 candidate effectors. Lastly, an analysis of the key transcriptional regulators and circuits for the T3SS families revealed that low-level T3SS regulators were more conserved than higher-level regulators. This comprehensive analysis of the T3SSs and their protein effectors provides new insight into the diversity of systems used to facilitate host-bacterial interactions.

Rice white tip nematode, Aphelenchoides besseyi, is a kind of plant parasitic nematodes that cause serious losses in rice and many other crops. Fatty acid and retinoid binding protein (FAR) is a specific protein in nematodes and is related to development, reproduction, infection to the host, and disruption of plant defense reactions, so the inhibition of FAR function is the potential approach to control A. besseyi. The full-length of Ab-far-1 cDNA is 805 bp, including 546 bp of ORF that encodes 181 amino acids. Software analysis revealed that the Ab-FAR-1 was rich in α-helix structure, contained a predicted consensus casein kinase II phosphorylation site and a hydrophobic secretory signal peptide, but did not have glycosylation sites. The Ab-FAR-1 had 52% homology to Gp-FAR-1 protein. The Ab-FAR-1 and Gp-FAR-1 were grouped in the same branch according to the phylogenetic tree. Fluorescence-based ligand binding analysis confirmed that the recombinant Ab-FAR-1 (rAb-FAR-1) bound with the fluorescent analogues 11-((5-dimethylaminonaphthalene-1-sulfonyl) amino) undecannoic acid (DAUDA), cis-parinaric acid and retinol, but the oleic acid would compete with the binding site. Quantitative PCR (qPCR) was used to assess the expression level of Ab-far-1 at different development stages of A. besseyi, the highest expression was found in the females, followed by eggs, juveniles and males. Using in situ hybridization technique, Ab-far-1 mRNA was present in the hypodermis of juveniles and adults, the ovaries of females and the testes of males. When A. besseyi was treated with Ab-far-1 dsRNA for 48 h, the silencing efficiency of Ab-far-1 was the best and the number of nematodes on the carrot was the least. Thus FAR plays important roles in the development and reproduction of nematodes. This study is useful and helpful to figure out a new way to control the plant parasitic nematodes.

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Geographic information systems (GIS) data/methods offer good promise for public health programs including obesity-related research. This study systematically examined their applications and identified gaps and limitations in current obesity-related research. A systematic search of PubMed for studies published before 20 May 2016, utilizing synonyms for GIS in combination with synonyms for obesity as search terms, identified 121 studies that met our inclusion criteria. We found primary applications of GIS data/methods in obesity-related research included (i) visualization of spatial distribution of obesity and obesity-related phenomena, and basic obesogenic environmental features, and (ii) construction of advanced obesogenic environmental indicators. We found high spatial heterogeneity in obesity prevalence/risk and obesogenic environmental factors. Also, study design and characteristics varied considerably across studies because of lack of established guidance and protocols in the field, which may also have contributed to the mixed findings about environmental impacts on obesity. Existing findings regarding built environment are more robust than those regarding food environment. Applications of GIS data/methods in obesity research are still limited, and related research faces many challenges. More and better GIS data and more friendly analysis methods are needed to expand future GIS applications in obesity-related research.