Coliform Depuration Of Chesapeake Bay Oysters

Oysters contaminated in nature depurated fecal coliforms to levels below 50/100 g in 48 hr over a wide range of environmental conditions typical of the lower Chesapeake Bay region. Temperature was found to be the most crilical environmental factor with conditions below 10-12°C having the potential of inhibiting depuration. Coliform clearance did not appear to be correlated with pumping rate or biodeposition activity of oysters. Oysters infected with the pathogens Dermocystidium marinum and Minchinia nelsoni (MSX) depurated as rapidly as uninfected ones. Meat quality and size of oysters likewise did not affect depuration. Four commercial-size tanks of different designs were found to yield satisfactory results in 48 hr. Water flow rates over the ranges studied and location of trays within the tanks did not influence depuration. Biodeposits contained high levels of total and fecal coliforms, but their accumulation in the tanks did not have a detrimental effect under the conditions studied. Pooling oysters during monitoring of\u27 depuration samples was necessary due lo the variation of coliform levels in individual oysters. Samples of 6-8 pooled oysters appeared to be adequate for estimating coliform levels. The Medium A-1 test was superior to the elevated temperature coliform plate_ (ETCP) procedure of Cabelli and Heffernan for determination of fecal coliforms in oysters.https://scholarworks.wm.edu/vimsbooks/1020/thumbnail.jp

‘Follow the Water’: Microbial Water Acquisition in Desert Soils

Water availability is the dominant driver of microbial community structure and function in desert soils. However, these habitats typically only receive very infrequent large-scale water inputs (e.g., from precipitation and/or run-off). In light of recent studies, the paradigm that desert soil microorganisms are largely dormant under xeric conditions is questionable. Gene expression profiling of microbial communities in desert soils suggests that many microbial taxa retain some metabolic functionality, even under severely xeric conditions. It, therefore, follows that other, less obvious sources of water may sustain the microbial cellular and community functionality in desert soil niches. Such sources include a range of precipitation and condensation processes, including rainfall, snow, dew, fog, and nocturnal distillation, all of which may vary quantitatively depending on the location and geomorphological characteristics of the desert ecosystem. Other more obscure sources of bioavailable water may include groundwater-derived water vapour, hydrated minerals, and metabolic hydro-genesis. Here, we explore the possible sources of bioavailable water in the context of microbial survival and function in xeric desert soils. With global climate change projected to have profound effects on both hot and cold deserts, we also explore the potential impacts of climate-induced changes in water availability on soil microbiomes in these extreme environments

Perception of a conserved family of plant signalling peptides by the receptor kinase HSL3

Plant genomes encode hundreds of secreted peptides; however, relatively few have been characterised. We report here an uncharacterised, stress‐induced family of plant signalling peptides, which we call CTNIPs. Based on the role of the common co‐receptor BRASSINOSTEROID INSENSITIVE 1‐ASSOCIATED KINASE 1 (BAK1) in CTNIP‐induced responses, we identified in Arabidopsis thaliana the orphan receptor kinase HAESA‐LIKE 3 (HSL3) as the CTNIP receptor via a proteomics approach. CTNIP binding, ligand‐triggered complex formation with BAK1, and induced downstream responses all involve HSL3. Notably, the HSL3‐CTNIP signalling module is evolutionarily conserved amongst most extant angiosperms. The identification of this novel signalling module will further shed light on the diverse functions played by plant signalling peptides and will provide insights into receptor-ligand co‐evolution

2013-2014 Kentucky & Tennessee Tobacco Production Guide

Tobacco growers in Kentucky and Tennessee have faced many challenges during the past two years, including weather, labor availability, and rising production costs. However, there have been opportunities as well. Some buying stations have closed or moved, but new buyers have come into the market and contract volumes have been stable overall. Good quality burley tobacco is in relatively short supply, and this has offered opportunities to those who have been able to overcome weather and labor challenges and produce good crops. These changes have had different impacts in different regions of both states, based largely on where buying stations closed and opened. Dark tobacco contract volumes have been more stable than burley, but dark tobacco growers have had challenges as well, including shortages of wood and quality sawdust needed to produce dark-fired tobacco. Labor costs have continued to rise as tobacco growers struggled to keep pace with changes in the H-2A labor program that allows them to legally employ migrant workers. Uncertainty about future regulatory action still hangs over the entire tobacco industry but does not seem as foreboding as two years ago. Overall, tobacco remains an important commodity in the agricultural economy of the region as growers prepare for future seasons