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Several tick species, in what is now known as the subgenus Boophilus in the genus Rhipicephalus, are economically important ectoparasites of livestock and other ungulates; as vectors of pathogens that kill cattle, they remain among the most studied ticks in the world. Researchers have developed quantitative computer models of Rhipicephalus ticks since the early 1970s to study complex biological and ecological relationships that influence management or eradication of ticks and tick‐borne diseases. We review the 45‐yr history of Rhipicephalus (Boophilus) models, which were developed and applied first in Australia, 10 yr later in North and South America, then soon after in Africa. Models progressed from analytical models of a portion of tick life cycles, to simulation models of complete life cycles or ecoclimatic indices, to the current emphasis on GIS‐based bioclimatic envelope models estimated from remotely sensed data and tick presence records. Earlier models were used primarily to predict effects of management techniques, such as use of sterile hybrid ticks, pasture rotation, acaricides, vaccines, and resistant cattle, while more recent models have been used to predict the potential for range expansion, especially due to global climate change and wildlife hosts, as well as in the face of competition with other tick species. We summarize characteristics of these models and compare those of population dynamics and bioclimatic envelope models. We discuss the past and present utility of these models and provide a perspective on future Rhipicephalus (Boophilus) modeling efforts.

Wild plants can contribute valuable genes to their domesticated relatives. Fertility barriers and a lack of genomic resources have hindered the effective use of crop-wild introgressions. Decades of research into barley's closest wild relative, Hordeum bulbosum, a grass native to the Mediterranean basin and Western Asia, have yet to manifest themselves in the release of a cultivar bearing alien genes. Here we construct a pangenome of bulbous barley comprising 10 phased genome sequence assemblies amounting to 32 distinct haplotypes. Autotetraploid cytotypes, among which the donors of resistance-conferring introgressions are found, arose at least twice, and are connected among each other and to diploid forms through gene flow. The differential amplification of transposable elements after barley and H. bulbosum diverged from each other is responsible for genome size differences between them. We illustrate the translational value of our resource by mapping non-host resistance to a viral pathogen to a structurally diverse multigene cluster that has been implicated in diverse immune responses in wheat and barley.

Background The purpose of this project was to identify metabolites, proteins, genes, and promoters associated with water stress responses in soybean. A number of these may serve as new targets for the biotechnological improvement of drought responses in soybean ( Glycine max ). Results We identified metabolites, proteins, and genes that are strongly up or down regulated during rapid water stress following removal from a hydroponics system. 163 metabolites showed significant changes during water stress in roots and 93 in leaves. The largest change was a root-specific 160-fold increase in the coumestan coumestrol making it a potential biomarker for drought and a promising target for improving drought responses. Previous reports suggest that coumestrol stimulates mycorrhizal colonization and under certain conditions mycorrhizal plants have improved drought tolerance. This suggests that coumestrol may be part of a call for help to the rhizobiome during stress. About 3,000 genes were strongly up-regulated by drought and we identified regulators such as ERF, MYB, NAC, bHLH, and WRKY transcription factors, receptor-like kinases, and calcium signaling components as potential targets for soybean improvement as well as the jasmonate and abscisic acid biosynthetic genes JMT , LOX1 , and ABA1 . Drought stressed soybean leaves show reduced mRNA levels of stomatal development genes including FAMA -like, MUTE -like and SPEECHLESS -like bHLH transcription factors and leaves formed after drought stress had a reduction in stomatal density of 22.34 % and stomatal index of 17.56 %. This suggests that reducing stomatal density may improve drought tolerance. MEME analyses suggest that ABRE (CACGT/CG), CRT/DRE (CCGAC) and a novel GTGCnTGC/G element play roles in transcriptional activation and these could form components of synthetic promoters to drive expression of transgenes. Using transformed hairy roots, we validated the increase in promoter activity of GmWRKY17 and GmWRKY67 during dehydration and after 20 μM ABA treatment. Conclusions Our toolbox provides new targets and strategies for improving soybean drought tolerance and includes the coumestan coumestrol, transcription factors that regulate stomatal density, water stress-responsive WRKY gene promoters and a novel DNA element that appears to be enriched in water stress responsive promoters.

Copper is an essential element that becomes highly cytotoxic when concentrations exceed the capacity of cells to sequester the ion. Here, we identify a new copper-specific repressor (CsoR) of a copper-sensitive operon ( cso ) in Mycobacterium tuberculosis (Mtb) that is representative of a large, previously uncharacterized family of proteins (DUF156). Electronic and X-ray absorption spectroscopies reveal that CsoR binds a single-monomer mole equivalent of Cu( I ) to form a trigonally coordinated (S 2 N) Cu( I ) complex. The 2.6-Å crystal structure of copper-loaded CsoR shows a homodimeric antiparallel four-helix bundle architecture that represents a novel DNA-binding fold. The Cu( I ) is coordinated by Cys36, Cys65′ and His61′ in a subunit bridging site. Cu( I ) binding negatively regulates the binding of CsoR to a DNA fragment encompassing the operator-promoter region of the Mtb cso operon; this results in derepression of the operon in Mtb and the heterologous host Mycobacterium smegmatis . Substitution of Cys36 or His61 with alanine abolishes Cu( I )- and CsoR-dependent regulation in vivo and in vitro . Potential roles of CsoR in Mtb pathogenesis are discussed.

Water and salt stresses are among the most important global problems that limit the growth and production of several crops. The current study aims at the possibility of mitigating the effect of deficit irrigation of common bean plants growing in saline lands by foliar spraying with selenium via the assessment of growth, productivity, physiological, and biochemical measurements. In our study, two field-based trials were conducted in 2017 and 2018 to examine the influence of three selenium (Se) concentrations (0 (Se0), 25 (Se25), and 50 mg L−1 (Se50)) on common bean plants grown under full irrigation (I100 = 100% of the crop evapotranspiration; ETc) and deficit irrigation (I80 = 80% of ETc, and I60 = 60% of ETc). Bean plants exposed to water stress led to a notable reduction in growth, yield, water productivity (WP), water status, SPAD value, and chlorophyll a fluorescence features (Fv/Fm and PI). However, foliar spraying of selenium at 25 or 50 mg L−1 on stressed bean plants attenuated the harmful effects of water stress. The findings suggest that foliage application of 25 or 50 mg L−1 selenium to common bean plants grown under I80 resulted in a higher membrane stability index, relative water content, SPAD chlorophyll index, and better efficiency of photosystem II (Fv/Fm, and PI). Water deficit at 20% increased the WP by 17%; however, supplementation of 25 or 50 mg L−1 selenium mediated further increases in WP up to 26%. Exogenous application of selenium (25 mg L−1 or 50 mg L−1) to water-stressed bean plants elevated the plant defense system component, given that it increased the free proline, ascorbic acid, and glutathione levels, as well as antioxidant enzymes (SOD, APX, GPX, and CAT). It was concluded that the application of higher levels (25 or/and 50 mg L−1) of Se improves plant water status as well as the growth and yield of common beans cultivated in saline soil.

Phloem-derived amino acids are the major source of nitrogen supplied to developing seeds. Amino acid transfer from the maternal to the filial tissue requires at least one cellular export step from the maternal tissue prior to the import into the symplasmically isolated embryo. Some members of UMAMIT (usually multiple acids move in an out transporter) family (UMAMIT11, 14, 18, 28, and 29) have previously been implicated in this process. Here we show that additional members of the UMAMIT family, UMAMIT24 and UMAMIT25, also function in amino acid transfer in developing seeds. Using a recently published yeast-based assay allowing detection of amino acid secretion, we showed that UMAMIT24 and UMAMIT25 promote export of a broad range of amino acids in yeast. In plants, UMAMIT24 and UMAMIT25 are expressed in distinct tissues within developing seeds; UMAMIT24 is mainly expressed in the chalazal seed coat and localized on the tonoplast, whereas the plasma membrane-localized UMAMIT25 is expressed in endosperm cells. Seed amino acid contents of umamit24 and umamit25 knockout lines were both decreased during embryogenesis compared with the wild type, but recovered in the mature seeds without any deleterious effect on yield. The results suggest that UMAMIT24 and 25 play different roles in amino acid translocation from the maternal to filial tissue; UMAMIT24 could have a role in temporary storage of amino acids in the chalaza, while UMAMIT25 would mediate amino acid export from the endosperm, the last step before amino acids are taken up by the developing embryo.

The present study employs a framework of residents’ emotional solidarity with tourists (e.g., welcoming nature, emotional closeness and sympathetic understanding), and tourism’s positive-negative impacts to understand residents’ support for tourism. The Research model was tested using a sample of 405 residents living in Alanya/Turkey. Data were collected using a face-to-face survey. Alternative models were used to test the theoretical structure of this study. The validity and credibility of the constructs were tested through confirmatory factor analysis, while its hypotheses were tested using path analysis. In Model 1, the dimensions of emotional solidarity and the positive and negative impacts of tourism and their direct effects on support for tourism were examined, and Model 2 showed results similar to those in Model 1. Results revealed that welcoming nature and sympathetic understanding had a positive effect on the positive impacts of tourism. However, emotional closeness did not affect the positive impacts associated with tourism. Regarding residents’ support, welcoming nature had the greatest positive effect on the support for tourism compared to other dimensions included in the framework of emotional solidarity, emotional closeness, and sympathetic understanding. The results of this study could enhance destination marketing managers when they need to understand residents’ support for tourism development.

Consumers are likely to see higher prices for beef and chicken at grocery stores as grilling season kicks off over the Memorial Day weekend, said a Texas A&M AgriLife Extension Service expert. David Anderson, Ph.D., AgriLife Extension economist in the Texas A&M College of Agriculture and Life Sciences Department of Agricultural Economics, Bryan-College Station, said year-over-year prices for beef and chicken were up while prices for pork cuts fell slightly. The per pound price differences give consumers grilling options, and the ability to find even better deals at grocery stores through discounts or specials going into the Memorial Day holiday and beyond.

Essential steps to take before cleaning up after flooding Any losses of livestock, damaged equipment, machinery, agricultural structures, fences, and water wells must be documented with digital images to provide further proof of loss. Standing water will prevail for many days following the recent rainfall, but homeowners should drain any flowerpots, pet dishes, or containers that may hold standing water to prevent mosquito breeding grounds. The Texas Department of Agriculture State of Texas Agriculture Relief Fund, STAR Fund, also provides resources for farmers, ranchers, and agribusinesses impacted by natural disasters.