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The ecological niche centrality hypothesis states that population abundance is determined by the position in the ecological niche, expecting higher abundances towards the center of the niche and lower at the periphery. However, the variations in the conditions that favor the persistence of populations between the center and the periphery of the niche can be a surrogate of stress factors that are reflected in the production of metabolites in plants. In this study we tested if metabolomic similarity and diversity in populations of the tree species Eucryphia cordifolia Cav. vary according to their position with respect to the structure of the ecological niche. We hypothesize that populations growing near the centroid should exhibit lower metabolites diversity than plants growing at the periphery of the niche. The ecological niche of the species was modeled using correlative approaches and bioclimatic variables to define central and peripheral localities from which we chose four populations to obtain their metabolomic information using UHPLC-DAD-QTOF-MS. We observed that populations farther away from the centroid tend to have higher metabolome diversity, thus supporting our expectation of the niche centrality hypothesis. Nonetheless, the Shannon index showed a marked variation in metabolome diversity at the seasonal level, with summer and autumn being the periods with higher metabolite diversity compared to winter and spring. We conclude that both the environmental variation throughout the year in combination with the structure of the ecological niche are relevant to understand the variation in expression of metabolites in plants.

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Oceanic mesoscale systems are characterized by inherent variability. Climatic change adds entropy to this system, making it a highly variable environment in which marine species live. Being at the higher levels of the food chain, predators maximize their performance through plastic foraging strategies. Individual variability within a population and the possible repeatability across time and space may provide stability in a population facing environmental changes. Therefore, variability and repeatability of behaviors, particularly diving behavior, could play an important role in understanding the adaptation pathway of a species. This study focuses on characterizing the frequency and timing of different dives (termed simple and complex) and how these are influenced by individual and environmental characteristics (sea surface temperature, chlorophyll a concentration, bathymetry, salinity, and Ekman transport). This study is based on GPS and accelerometer-recorded information from a breeding group of 59 Black-vented Shearwater and examine consistency in diving behavior at both individual and sex levels across four different breeding seasons. The species was found to be the best performing free diver in the Puffinus genus with a maximum dive duration of 88 s. Among the environmental variables assessed, a relationship was found with active upwelling conditions enhancing low energetic cost diving, on the contrary, reduced upwelling and warmer superficial waters induce more energetically demanding diving affecting diving performance and ultimately body conditions. The body conditions of Black-vented Shearwaters in 2016 were worse than in subsequent years, in 2016, deepest and longest complex dives were recorded, while simple dives were longer in 2017-2019. Nevertheless, the species' plasticity allows at least part of the population to breed and feed during warmer events. While carry-over effects have already been reported, the effect of more frequent warm events is still unknown.

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The aim of this study was to evaluate some physiological parameters as total locomotor activity and subcutaneous temperature in two different bovine breeds under tropical environment. In this study, total locomotor activity and subcutaneous temperature were evaluated in 18 clinically healthy female cows. All cows were divided into 3 groups: group A1 was constituted by 6 Holstein Bos taurus, group A2 was constituted by 6 female Herford Bos taurus cows, and group B was constituted by 6 female Bradford Bos indicus cows. Data recording of total locomotor activity (TLA) and subcutaneous temperature (ST) was performed by means of a subcutaneous thermometer (Thermocron) and an actimeter ACTIWATCH® (Cambridge Neurotechnology Ltd.) based on accelerometer technologies equipped on all subjects to record TLA. At the same time, thermal and hygrometric recording were carried out, considering the subtropical climate of Santa Fe. The application of GLM for statistical analysis showed a significant effect (P < 0.05) on statistical model and time of the day on TLA and ST for all groups; no significative effects on animal parameters were found for ST and TLA except for group B. Circadian parameters have been evaluated according to the single cosinor procedure of ST that showed a diurnal daily rhythmicity for all investigated groups and TLA which is focused almost during the photophase for groups A1 and A2 and during scotophase for group B. Considering different species and breeds, and different environmental conditions, this study suggested that some subjects may be much more able to adapt themselves to environmental stress than others. During their evolution from Bos taurus, zebu cattle (Bos indicus) have acquired genes that confer thermotolerance. Subjects from Bos indicus breeds are better able to regulate body temperature in response to heat stress than Bos taurus subjects.

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This work aimed to study alternatives to the chemical management of italian ryegrass (Lolium multiflorum), taking into account environmental and biological factors at the time of herbicide application, as well as the possible differential response among biotypes of the species. The objective of this study was to evaluate the influence of air temperature on the chemical control of two ryegrass biotypes. The experiment was conducted in a greenhouse, in a completely randomized design with four replicates and organized in a 2x2x10 factorial scheme (biotype, temperature and herbicide). One biotype was obtained from an area with annual crops and the other from a perennial crop. The tested herbicides were: clethodim, clodinafop-propargyl, fenoxapropp-ethyl+clethodim, glyphosate, iodosulfuronmethyl, paraquat, paraquat+diuron, sethoxydim and tepraloxydim. The application occurred in plants maintained in air temperature of 20-22ºC and 30- 34ºC. The control was evaluated at 7, 14, 21 and 28 days after application of the treatments, assigning the percentage of 0 to 100 that corresponded to the absence of injury and death of the plants, respectively. The data was submitted to analysis of variance and the means were compared by the Tukey test (P=0.05). In general, herbicides were more effective at a temperature of 20-22ºC, and the temperature of 30- 34ºC impaired ryegrass control. The susceptibility to the grass killers was dependent on the biotype in application under temperature of 30-34 °C.(AU)

Este trabalho visou estudar alternativas para o manejo químico de azevém (Lolium multiflorum), levando em consideração fatores ambientais e biológicos no momento da aplicação dos herbicidas, bem como a possível resposta diferencial entre biótipos da espécie. Objetivou-se avaliar a influência da temperatura do ar no controle químico de dois biótipos de azevém. O experimento foi conduzido em casa de vegetação, em delineamento inteiramente casualizado com quatro repetições e organizado em esquema fatorial 2x2x10 (biótipo, temperatura e herbicida). Um biótipo foi proveniente de área com cultivos anuais e o outro, de cultivo perene. Os herbicidas testados foram: clethodim, clodinafop-propargyl, fenoxapropp-ethyl+clethodim, glyphosate, iodosulfuronmethyl, paraquat, paraquat+diuron, sethoxydim e tepraloxydim. A aplicação ocorreu em plantas mantidas sob temperatura do ar de 20-22 ºC e 30-34 ºC. O controle foi avaliado aos 7, 14, 21 e 28 dias após a aplicação dos tratamentos, atribuindo-se o percentual de 0 a 100 que correspondeu à ausência de injúria e morte das plantas, respectivamente. Os dados foram submetidos à análise de variância e as médias comparadas pelo teste de Tukey (P=0,05). Em geral, os herbicidas foram mais eficazes em temperatura de 20-22 ºC, sendo que a temperatura de 30-34 ºC prejudicou o controle do azevém. A suscetibilidadeaos graminicidas foi dependente do biótipo em aplicação sob temperatura de 30-34 ºC. (AU)

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This work aimed to study alternatives to the chemical management of italian ryegrass (Lolium multiflorum), taking into account environmental and biological factors at the time of herbicide application, as well as the possible differential response among biotypes of the species. The objective of this study was to evaluate the influence of air temperature on the chemical control of two ryegrass biotypes. The experiment was conducted in a greenhouse, in a completely randomized design with four replicates and organized in a 2x2x10 factorial scheme (biotype, temperature and herbicide). One biotype was obtained from an area with annual crops and the other from a perennial crop. The tested herbicides were: clethodim, clodinafop-propargyl, fenoxapropp-ethyl+clethodim, glyphosate, iodosulfuronmethyl, paraquat, paraquat+diuron, sethoxydim and tepraloxydim. The application occurred in plants maintained in air temperature of 20-22ºC and 30- 34ºC. The control was evaluated at 7, 14, 21 and 28 days after application of the treatments, assigning the percentage of 0 to 100 that corresponded to the absence of injury and death of the plants, respectively. The data was submitted to analysis of variance and the means were compared by the Tukey test (P=0.05). In general, herbicides were more effective at a temperature of 20-22ºC, and the temperature of 30- 34ºC impaired ryegrass control. The susceptibility to the grass killers was dependent on the biotype in application under temperature of 30-34 °C.

Este trabalho visou estudar alternativas para o manejo químico de azevém (Lolium multiflorum), levando em consideração fatores ambientais e biológicos no momento da aplicação dos herbicidas, bem como a possível resposta diferencial entre biótipos da espécie. Objetivou-se avaliar a influência da temperatura do ar no controle químico de dois biótipos de azevém. O experimento foi conduzido em casa de vegetação, em delineamento inteiramente casualizado com quatro repetições e organizado em esquema fatorial 2x2x10 (biótipo, temperatura e herbicida). Um biótipo foi proveniente de área com cultivos anuais e o outro, de cultivo perene. Os herbicidas testados foram: clethodim, clodinafop-propargyl, fenoxapropp-ethyl+clethodim, glyphosate, iodosulfuronmethyl, paraquat, paraquat+diuron, sethoxydim e tepraloxydim. A aplicação ocorreu em plantas mantidas sob temperatura do ar de 20-22 ºC e 30-34 ºC. O controle foi avaliado aos 7, 14, 21 e 28 dias após a aplicação dos tratamentos, atribuindo-se o percentual de 0 a 100 que correspondeu à ausência de injúria e morte das plantas, respectivamente. Os dados foram submetidos à análise de variância e as médias comparadas pelo teste de Tukey (P=0,05). Em geral, os herbicidas foram mais eficazes em temperatura de 20-22 ºC, sendo que a temperatura de 30-34 ºC prejudicou o controle do azevém. A suscetibilidadeaos graminicidas foi dependente do biótipo em aplicação sob temperatura de 30-34 ºC.

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Population fluctuations of Ceratitis capitata (Wiedemann) were evaluated over a period of 12 mo in four altitudinal strata (400-750, 750-1,100, 1,100-1,450, and 1,450-1,800 meters above sea level, masl) in Eastern Guatemala. Within each altitudinal range, sampling plots were established in coffee plantations and adjacent areas, in which Jackson traps were set and baited with Trimedlure. Coffee berries and other host fruits were collected. Population density was lowest at the 400-750 masl stratum and highest at 1,450-1,800 masl. At every altitudinal range, the fluctuations of the pest were associated mainly with the availability of ripe coffee berries as a primary host. From 750-1,450 masl, the pest was also associated with the availability of sweet orange and mandarins in commercial and backyard orchards. The highest densities of the pest were recorded in the dry season. Citrus were the main alternate host where ripe coffee berries were not available. This knowledge on population dynamics of C. capitata will contribute to develop more effective area-wide pest management strategies including the use of sterile insects, natural enemies, and bait sprays.

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