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This study assessed potential impacts of climate on the dynamics of soybean-maize systems, a widespread cropping practice in Central Brazil, in regions of Mato Grosso state. Baseline (historical) and future climate scenarios in the mid and end of the twenty-first century were locally defined. Climate projections were input in a crop model, which was used to analyze their impact on first season's crop (soybean), and more emphasis was given on the second season's crop, maize development. In the climate projections, we observed a generalized increase in temperature for all scenarios, with variability of rainfall amount and pattern. Soybean growth showed a general enlargement of cycle length (average of up to 16%) and increase of yields (average of up to 34%) in future conditions. Soybean sowing dates and future climate contributed to the shortening of recommended maize sowing window and yield decreases. At most extreme scenarios of future climate, only soybean sown at the earliest dates would enable the latest maize sowing dates, bringing the greatest losses to the latter crop. Estimated maize yields showed relative average variations from baseline of − 22.5% and − 32.5% in RCP 4.5 in the mid and end of the century, while variations were of − 34% and − 55% in RCP 8.5 in the mid and end of the century, respectively. Timing of soybean sowing dates in a future climate will become more important in influencing the dynamics of subsequent maize's sowing dates and yields under a more extreme and unfavorable climate for its development.

The water content reflectometer allows a temporal and spatial assessment in soil water dynamic. This work aimed to study the behavior of the sensor (CS616) for the period measurement in function to the temperature and soil water content. The tests were conducted at State University of Mato Grosso, Tangara da Serra municipality. We used PVC (polymerizing vinyl chloride) pipe to make six recipients (0.1 m diameter and 0.4 m height) and filled them with soil. For each one of them a sensor CS616 and temperature sensor (K type) were allocate in a central position. The soil water content for each recipient were fitted to 0.00; 0.06; 0.11; 0.16; 0.22; 0.27 m 3 m -3 , and the samples were submitted to temperature gradient from 1.0 up to 40.0 °C. Data of temperature, and period response were recorded in a data logger. Notice that the temperature provides changes for period response values (μs), and as greater the soil water content, as greater the temperature influence. From collected data, two models were fitted (linear and quadratic), and compared with manufacturer standard equations. For conditions in that study, the fitted quadratic model provide the best approach for the water soil content prediction.Additional keywords: CS616, sensor, time domain reflectometry. ResumoOs sensores de reflectometria permitem a avaliação temporal e contínua da dinâmica da água no solo. O objetivo deste trabalho foi avaliar a leitura (período) do sensor (CS616) em função do teor de água e da temperatura do solo, para a predição da umidade do solo. O estudo foi realizado na Universidade do Estado de Mato Grosso, no Câmpus Universitário de Tangará da Serra. Foram construídos seis tubos de PVC, nos quais foram acondicionados solo em seus interiores, sendo que em cada tubo foi instalado um sensor CS616 e um sensor de temperatura tipo "K". Posteriormente, condicionou-se o solo de cada tubo nas umidades volumétricas 0,00; 0,06; 0,11; 0,16; 0,22 e 0,27 m 3 m -3 , submetendo-os a um gradiente de temperatura de 1,0 até 40,0 °C. Os valores de temperatura e do período foram registrados e armazenados em um sistema de aquisição de dados. Observou-se que a temperatura influencia nas mensurações do período (µs), tendo maior influência à medida que se aumenta a umidade do solo. Uma vez constatada a referida influência, ajustou-se um modelo linear e outro quadrático que representassem o comportamento dos dados, comparando-os com as equações fornecidas pelo fabricante do sensor utilizado. Para as condições estudadas, a equação quadrática gerada neste trabalho gerou melhores resultados de predição da umidade volumétrica do solo em relação às demais.Palavras-chave adicionais: CS616, reflectometria no domínio do tempo, sensor.

Climate change promotes variations in climatic elements necessary for crop growth and development, such as temperature and rainfall, potentially impacting yields of staple crops. The objective of this study was to assess future climate projections, derived from Intergovernmental Panel on Climate Change, and their impacts on second season maize in a region of Mato Grosso state. Field experiments in the 15/16 season comprising different sowing dates and hybrids maturities in rainfed conditions were used for crop model adjustment and posterior simulation of experiments. Crop simulations comprised historical (1980-2010) and future (2010-2100) time frames combined with local crop management practices. Results showed decreases of 50-89% in grain yields, with the most pessimistic scenarios at the latest sowing date at the end of the century. Decreases in the duration of crop cycle and in the efficiency of water use were observed, indicating the negative impacts of projected higher temperatures and drier conditions in crop development. Results highlight the unfeasibility of practicing late sowing dates in second season for maize in the future, indicating the necessity of adjusting management practices so that the double-cropping production system is possible.

With the objective of determining maize’s specific water requirements in different soil cover conditions in a Cerrado region of Mato Grosso, Brazil, this study used the dual’s crop coefficient (Kc dual) approach, according to FAO methods. An experiment was carried out in 2016, with three treatments: without vegetation soil cover; soil cover of 4 t ha-1 and soil cover of 8 t ha-1 dry matter of brachiaria grass. The used methodology accounts for crop’s transpiration component (through its basal coefficient, Kcb) and soil evaporation component (through its coefficient, Ke), which were determined for initial, intermediate and final phases of crop development. Experiments were carried in lysimeters to determine crop’s evapotranspiration, and in microlysimeters to determine soil evaporation. Crop’s transpiration, on three soil coverage treatments, showed overall highest values for the treatment with greater coverage (Kcb maximum values of 0.88, 1.00 and 1.03 from the lowest to greater soil coverage), while between crop’s phases, coefficient values were always higher at the intermediate stage, presenting decreases with crop senescence. Soil evaporation was highest on treatment without coverage in all crop’s stages (Ke = 0.37-0.78) and lowest in the treatment with greater coverage (Ke = 0.11-0.35). Yields were higher on treatments with coverage (9929.18 and 9939.52 kg ha-1 for treatments with 4 and 8 t ha-1) and lower when cultivated in soil without cover (8264.67 kg ha-1). Despite relatively higher crop’s transpiration with greater soil coverage, this treatment was identified as the best management option in the assessed tropical region of Brazilian Cerrado, in terms of rational use of water, due to lowest losses through evaporation, as also providing the highest grain yields.

The CCCTC -binding factor (CTCF) is a protein involved in repression, activation, hormone-inducible gene silencing, functional reading of imprinted genes and X-chromosome inactivation. We analyzed CTCF gene expression in bovine peripheral blood, oocytes and in different cellular stages (2-4 cells, 8-16 cells, 16-32 cells, morulae, and blastocysts) of in vitro fertilized embryos. This is the first report of CTCF expression in oocytes and preimplantation bovine embryos and has implications for the production of embryonic stem cells and the development of novel medical technologies for humans.

The possibility to obtain reliable data on the chemical and physical characteristics of aerosols and the regularities in the processes of their formation and transportation under the background natural climatic conditions is a necessary requirement for verification of existing climate models [l, 2].

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