Effects of corticotropin releasing factor (CRF) on sleep and body temperature following controllable footshock stress in mice

Author: Yang, L.; Wellman, L.L.; Tang, X.; Sanford, L.D. Description: Rapid eye movement sleep (REM) is increased after controllable stress (modeled by escapable footshock, ES) and decreased after uncontrollable stress (modeled by inescapable footshock, IS). Decreases in REM after IS are exacerbated by corticotropin releasing factor (CRF) and attenuated by a CRF antagonist. In this study, we trained mice with ES following injections of CRF, astressin (AST), or saline (SAL) to determine whether CRF would alter REM after ES. Male BALB/cJ mice (n=7) were implanted for recording sleep, activity and…

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Consistent negative response of US crops to high temperatures in observations and crop models

Author: Schauberger, B.; Archontoulis, S.; Arneth, A.; Balkovic, J.; Ciais, P.; Deryng, D.; Elliott, J.; Folberth, C.; Khabarov, N.; Muller, C.; Pugh, T.A.M.; Rolinski, S.; Schaphoff, S.; Schmid, E.; Wang, X.; Schlenker, W.; Frieler, K. Description: High temperatures are detrimental to crop yields and could lead to global warming-driven reductions in agricultural productivity. To assess future threats, the majority of studies used process-based crop models, but their ability to represent effects of high temperature has been questioned. Here we show that an ensemble of nine crop models reproduces the observed…

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Impact of Nighttime Temperature on Physiology and Growth of Spring Wheat

Author: Prasad, P.V.V.; Pisipati, S.R.; Ristic, Z.; Bukovnik, U.; Fritz, A.K. Description: Climate models predict greater increases in nighttime temperature in the future. The impacts of high nighttime temperature on wheat (Triticum aestivum L.) are not well understood. Objectives of this research were to quantify the impact of high nighttime temperatures during reproductive development on phenology, physiological, vegetative, and yield traits of wheat. Two spring wheat cultivars (Pavon-76 and Seri-82) were grown at optimum temperatures (day/night, 24/14°C; 16/8 h light/dark photoperiod) from sowing to booting. Thereafter, plants were exposed to…

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Climate change impacts on soil erosion in Midwest United States with changes in crop management

Author: O’Neal, M.R.; Nearing, M.A.; Vining, R.C.; Southworth, J.; Pfeifer, R.A. Description: This study investigates potential changes in erosion rates in the Midwestern United States under climate change, including the adaptation of crop management to climate change. Previous studies of erosion under climate change have not taken into account farmer choices of crop rotations or planting dates, which will adjust to compensate for climate change. In this study, changes in management were assigned based on previous studies of crop yield, optimal planting date, and most profitable rotations under climate change…

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The fungal dimension of biodiversity: magnitude, significance, and conservation

Author: Hawksworth, D.L. Description: Fungi, members of the kingdoms Chromista, Fungi s.str. and Protozoa studied by mycologists, have received scant consideration in discussions on biodiversity. The number of known species is about 69 000, but that in the world is conservatively estimated at 1·5 million; six-times higher than hitherto suggested. The new world estimate is primarily based on vascular plant: fungus ratios in different regions. It is considered conservative as: (1) it is based on the lower estimates of world vascular plants; (2) no separate provision is made for the…

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Soil Compaction and Moisture Stress Preconditioning in Kentucky Bluegrass. II. Stomatal Resistance, Leaf Water Potential, and Canopy Temperature

Author: Agnew, M.L.; Carrow, R.N. Description: In this greenhouse study, we investigated the effects of soil compaction and moisture stress preconditioning on stomatal diffusive resistance (Rs), leaf water potential (Y1), and canopy minus air temperatures of Kentucky bluegrass (Poa pratensis L. ‘Ram I’). The compaction treatments were: (i) NC = no compaction, (ii) LT = long-term compaction over a 99-day period, and (iii) ST = short-term compaction for 9 days. The compactive treatment was equivalent to 720 J energy. Irrigation regimes were initiated at the same time as LT compaction…

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Identification of two phenotypes of Arabidopsis thaliana under in vitro salt stress conditions

Author: Ruiz Carrasco, K.B.; Baroni Fornasiero, R.; Tassoni, A.; Bagni, N. Description: This study describes two phenotypes of Arabidopsis thaliana (ecotype Columbia) developed in vitro under salt stress (75 mM NaCl). The phenotypes 01 and 02 appeared visibly distinguishable by rosette morphology and competence to produce flowers. Phenotype 01, sensible to salt stress, accumulated high quantities of Na+, showed a slight reduction in dry mass, and high protein and chlorophyll contents. Moreover, its anatomy exhibited some xeromorphic traits. Phenotype 02, clearly salt tolerant, showed a morphology similar to control plants,…

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Heat-shock proteins induce heavy-metal tolerance in higher plants

Author: Neumann, D.; Lichtenberger, O.; Gnther, D.; Tschiersch, K.; Nover, L. Description: Cell cultures of Lycopersicon peruvianum L. stressed with CdSO4 (10−3M) show typical changes in the ultrastructure, starting with the plasmalemma and later on extending to the endoplasmic reticulum and the mitochondrial envelope. Part of the membrane material is extruded, with the formation of osmiophilic droplets which increase in size and number during the stress period. After 4 h, about 20‰ of the cells are dead. A short heat stress preceeding the heavy-metal stress induces a tolerance effect by…

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Effect of atmospheric CO2 on plant defense against leaf and root pathogens of Arabidopsis

Author: Zhou, Yeling; Van Leeuwen, Sanne K.; Pieterse, Corné M. J.; Bakker, Peter A. H. M.; Van Wees, Saskia C. M. Description: Climate change and the associated increase in atmospheric CO2 levels may affect the severity of plant diseases and threaten future crop yields. Here, we compared responses of the model plant Arabidopsis thaliana to leaf and root pathogens with hemi-biotrophic or necrotrophic infection strategies under pre-industrial, current, and future atmospheric CO2 conditions. Defenses against biotrophs are generally regulated by salicylic acid (SA) signaling, whereas jasmonic acid (JA) signaling controls…

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Species distribution and community organization in a Nebraska Sandhills mixed prairie as influenced by plant/soil-water relationships

Author: Barnes, Paul W.; Harrison, A. Tyrone Description: Plant and soil water relationships in a typical nebraska Sandhills prairie were examined to 1) explain the observed distribution patterns of several dominant grasses along a topographic gradient, and 2) show how spatial and temporal variations in soil moisture are critical to community organization on a sandy substrate. An experimental transect encompassing the major community and soil types along a steep, west-facing vegetated dune was established. Maximum available water was shown to be significantly higher in the fine textured surface soils of…

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