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Cowpeas are of high socioeconomic importance in the North and Northeast regions of Brazil, whereby the search for alternatives that offer increased productivity with financial returns has become an important challenge. Thus, the objective of this study was to estimate and evaluate the economic indicators of cowpea production in 2015 and 2016 when applying drip irrigation to different depths. Irrigation treatments were based on crop evapotranspiration (ETc). The experiment was laid in a randomized complete blocks design with four treatments (0, 25, 50, and 100% ETc) and six replications. For economic analysis, the results were extrapolated to an area of one hectare. Productivity in 2015 was lower than that in 2016; however, in all treatments, it was always higher when plants were grown under adequate water supply. In both years, the total operating costs were higher under irrigation than under rainfed conditions. The 100% ETc treatment resulted in a greater number of cowpea bags (60 kg) produced and a higher gross revenue than the rainfed treatment by 17 bags ha-1, equivalent to 1,020 kg ha-1 (gross revenue US$ 711.48) and 16 bags ha-1, equivalent to 960 kg ha-1 (gross revenue US$ 867.12), in 2015 and 2016, respectively. Water deficit limited cowpea yield in both years but made cultivation economically unfeasible only in 2015. RESUMO O feijão-caupi apresenta grande importância socioeconômica nas regiões Norte e Nordeste do Brasil, sendo que a busca por alternativas que ofereçam aumento de produtividade com retorno financeiro tem se tornado um importante desafio. Assim, o objetivo deste trabalho foi estimar e avaliar os indicadores econômicos da produção de feijão-caupi nos anos de 2015 e 2016 quando da aplicação de irrigação por gotejamento em diferentes lâminas. Os tratamentos de irrigação foram baseados na evapotranspiração da cultura (ETc). O experimento foi instalado em blocos ao acaso com quatro tratamentos (0, 25, 50 e 100% da ETc) e seis repetições. Para análise econômica, os resultados foram extrapolados para uma área de um hectare. A produtividade em 2015 foi inferior à de 2016; porém, em todos os tratamentos, a produtividade foi sempre maior quando as plantas foram cultivadas sob irrigação adequada. Em ambos os anos, os custos operacionais totais foram maiores sob irrigação do que sob condições de sequeiro. O tratamento 100% ETc resultou em maior número de sacas de feijão-caupi (60 kg) produzidas e receita bruta superior ao tratamento de sequeiro em 17 sacas ha-1, equivalente a 1.020 kg ha-1 (receita bruta US$ 711,48) e 16 sacas ha-1, equivalente a 960 kg ha-1 (receita bruta US$ 867,12), em 2015 e 2016, respectivamente. A deficiência hídrica limitou a produtividade do feijão-caupi nos dois anos, mas inviabilizou economicamente o cultivo apenas em 2015.

In the 21st century, existing human societies and biodiversity on the Earth are under threat because human resource consumption is exceeding or projected to exceed some of the physical and chemical boundaries of our planet (Rockström et al., 2009). Space research and space exploration are an integral part of a sustainable development that mitigates these threats: Space science and exploration allow us to monitor environmental threats and they open up access to global communication and participation for all human societies. In addition, space exploration also promises to expand the existing limitations and planetary boundaries imposed on human development. On the other hand space exploration can also cause additional environmental problems. The best known example for the latter is the anthropogenic space debris orbiting Earth, but similar problems are likely to occur in other places, for instance on the Moon, due to scientific and commercial space exploration in the near future. Planetary sustainability is a helpful concept to address the promises and challenges posed by space exploration with respect to sustainability. This concept can be understood as a sustainable development that considers the Earth as a planet in its space environment and considers the space environment as an integral part of sustainable development, with scientific, ethical, economic, and legal ramifications. In this article we review the recent advancements in planetary sustainability. This includes the proposal that the space environment of Earth should be added as an independent goal to the existing 17 Sustainable Development Goals defined by the United Nations, considerations of the planned return of humans to the Moon in 2024, and the implications of the increase of commercial satellite networks in low Earth orbit.

The selection of lima bean accessions in the fresh and dry stages is an excellent tool to increase crop yield in Brazil and ensure a source of vegetable protein for the population. Principal component analysis and nonparametric indices can be used to identify promising accessions based on the desired agronomic variables. The aim of the present study was to select accessions from traditional lima bean varieties in the fresh and dry stages using principal component analysis and nonparametric selection indices. The experiment consisted of a randomized block design, evaluating 13 treatments in four replicates. The experimental plot contained 20 plants in its study area. The first two principal components for the two stages explained more than 80% of the variation found among the accessions. The Mulamba & Mock and Genotype-Ideotype selection indices were efficient in classifying promising varieties for breeding programs. The UFPI 1111 accession can be used in fresh lima bean production, and its UFPI 1248 and 1294 counterparts in lima bean breeding programs. RESUMO A seleção de acessos de feijão-fava nos estádios verde e seco é uma excelente ferramenta para aumentar a produtividade da cultura no país e garantir uma fonte de proteína vegetal para a população. O uso de componentes principais e índices de seleção não-paramétricos podem ser utilizados para identificar acessos promissores com base em características agronômicas desejáveis. O objetivo do presente estudo foi selecionar acessos de variedades crioulas de feijão-fava nos estádios frescos e secos utilizando componentes principais e índices de seleção não paramétricos. O experimento foi disposto em delineamento em blocos casualizados, sendo avaliados 13 tratamentos em quatro repetições. A parcela experimental conteve 20 plantas em sua área útil. Os dois primeiros componentes principais, para os dois estádios, explicaram mais de 80% da variação encontrada entre os acessos. Os índices de seleção de Mulamba & Mock e Genótipo-Ideótipo foram eficientes na classificação de variedades promissoras para programas de melhoramento. O acesso UFPI 1111 pode ser direcionado para a produção de fava verde, e os acessos UFPI 1248 e UFPI 1294 podem ser utilizados para programas de melhoramento de fava seca.

Coffee plantations installed at high altitudes and near forested areas have been highly infested with Anredera cordifolia. The objective of this work was to evaluate the effectiveness of different pre- and post-emergence herbicide treatments on A. cordifolia after mechanical mowing. A field experiment was carried out in a coffee plantation with natural infestation of A. cordifolia in a completely randomized design with a split-plot scheme and four replicates, in which the main plot an herbicides application and the subplot was the days after the initial application (DAI). The treatments were as follows: saflufenacil + glyphosate (70 + 960 g a.i. ha-1); chlorimuron + glyphosate (80 + 960 g a.i. ha-1); metsulfuron + glyphosate (6 + 960 g a.i. ha-1); flumioxazin + glyphosate (25 + 960 g a.i. ha-1), and glyphosate (960 g a.i. ha-1); with sequential application of glyphosate (960 g a.i. ha-1); glyphosate + indaziflam (960 + 75 g a.i. ha-1); indaziflam (75 g a.i. ha-1); and a control without herbicide application. Mechanical control, followed by the application of the treatments flumioxazin + glyphosate and metsulfuron + glyphosate in the first application and sequential application of indaziflam, proved to be effective. Control of this weed should be based on the removal of its plant residues from the field to reduce the regrowth and germination of aerial tubers. RESUMO Plantações de café instaladas em altitudes elevadas e próximas a áreas florestais têm sido altamente infestadas por Anredera cordifolia. O objetivo deste estudo foi avaliar a eficácia de diferentes tratamentos herbicidas pré e pós-emergência sobre A. cordifolia após roçada mecânica. Para tanto, foi conduzido um experimento de campo em uma lavoura de café com infestação natural de A. cordifolia em um delineamento inteiramente casualizado com esquema de parcelas subdivididas com quatro repetições, sendo a parcela principal os tratamentos com aplicação de herbicida e a subparcela os dias após a aplicação inicial (DAI). Os tratamentos foram compostos por: saflufenacil + glifosato (70 + 960 g i. a. ha-1); clorimuron + glifosato (80 + 960 g i. a. ha-1); metsulfuron + glifosato (6 + 960 g i. a. ha-1); flumioxazin + glyphosate (25 + 960 g i. a. ha-1) e glifosato (960 g i. a. ha-1); com uma aplicação sequencial de: glifosato (960 g i. a. ha-1); (6) glifosato + indaziflam (960 g i. a. ha-1); e indaziflam (75 g i. a. ha-1), além de uma testemunha sem aplicação de herbicida. O manejo integrado é fundamental para o controle adequado de A. cordifolia, devido ao seu desenvolvimento vegetativo agressivo. O controle mecânico, seguido da aplicação dos tratamentos flumioxazin + glyphosate e metsulfuron + glyphosate na primeira aplicação e indaziflam sequencial mostrou-se eficaz. O controle dessa planta daninha deve ser baseado na remoção de seus resíduos vegetais do campo para reduzir a rebrota e a germinação de tubérculos aéreos.

Humans have stepped on the Lunar surface for less than 80 h of Extravehicular Activity, providing a narrow understanding of Lunar gait patterns. NASA’s Human-crewed Artemis missions are quickly approaching; understanding how fractional gravity affects gait patterns will be critical for the Moon’s and Mars’ long-term habitation. This study examined gait patterns under 1.0 g (Earth), simulated 0.38 g (Martian), and 0.17 g (Lunar). Participants walked and ran on a treadmill supported by ARGOS (Active Response Gravity Offload System), simulating fractional gravity. Vicon motion capture data and principal component analysis software were used to capture and quantify coordinated gait structures. There were found to be significant differences (p < 0.05) in the coordinative gait structures for ambulation between fractional gravity conditions. Additionally, there were significantly higher asymmetric gait components for Lunar conditions. Finally, a skipping coordinative structure was identified within Lunar and Martian running. Refereed/Peer-reviewed

Indices based on data from remote sensors play an important role in the characterization, mapping and monitoring of a drought event. Thus, the objective of this study was to monitor the dynamics of agricultural drought, through the response of vegetation, in the semi-arid region that comprises the state of Paraíba, Brazil, through MODIS satellite products applied to the VCI (vegetation condition index), TCI (temperature condition index) and VHI (vegetation health index) indices, and to evaluate the correspondence of VHI index with standardized precipitation index (SPI) and agricultural standardized precipitation index (aSPI). In this study, values of NDVI (normalized difference vegetation index) and LST (land surface temperature) - covering the period between 2010 and 2020 - were used to estimate VCI, TCI and VHI. In addition, the correspondence of VHI with SPI and aSPI was evaluated at the 12-month time scale, conducted using Pearson’s correlation analysis. Characteristics of a stressed vegetation predominated in the study region, due to irregularity of precipitation and high temperatures, confirming the possibility of detection of droughts through VHI, VCI and TCI, and that the indices detected remotely and through local data are strongly correlated in drought detection. RESUMO Os índices baseados em dados de sensores remotos desempenham um papel importante na caracterização, mapeamento e monitoramento de uma seca. Com isso, o objetivo deste estudo foi monitorar a dinâmica da seca agrícola, por meio da resposta da vegetação, na região semiárida que compreende o estado da Paraíba, Brasil, por meio de produtos de satélite MODIS aplicados ao VCI (índice de condição da vegetação), TCI (índice de condição térmica) e VHI (índice de saúde da vegetação). E também, avaliar a correspondência do índice VHI com o índice de precipitação padronizada (SPI) e o índice de precipitação padronizada agrícola (aSPI). Neste trabalho, as climatologias de NDVI (índice de vegetação por diferença normalizada) e LST (temperatura da superfície terrestre) - abrangendo o período entre 2010 e 2020 - foram usadas para estimar VCI, TCI e VHI. Além disso, foi avaliado a correspondência do VHI e o índice padronizado de precipitação (SPI) e índice agrícola de precipitação (aSPI), na escala de tempo de 12 meses, conduzidas usando a análise de correlação de Pearson. Na região de estudo predominaram características de uma vegetação estressada, devido à irregularidade de precipitação e altas temperaturas. Confirmando a possibilidade da detecção das secas através do VHI, VCI e TCI. E que os índices detectados remotamente e através de dados locais estão fortemente correlacionados na detecção de seca.

Nutritional management can be an efficient strategy to mitigate the effects of salinity on fruit production and quality. This study aimed to evaluate the production and quality of fruits of mini watermelon crop, Sugar Baby cultivar, grown in a protected environment, under salt stress and K+/Ca2+ ratios. The study was carried out in a greenhouse, using a randomized block design, 1 + 5 scheme, resulting in six treatments and four replications. Six nutrient solutions were employed, one using low-salinity water, with NaCl (0.5 dS m-1) and standard nutrient solution (S1, control treatment), and the others using salinized water at 5.0 dS m-1 (S2) and extra addition of K (S3 = 50% and S4 = 100%) and Ca (S5 = 50% and S6 = 100%). The production (fruit production, longitudinal and transverse diameter of fruit, rind thickness, pulp firmness) and postharvest quality (soluble solids, vitamin C, titratable acidity, and maturation index), in addition to the variables related to the color of the pulp (lightness, chroma index, and Hue angle) were evaluated. The addition of NaCl reduced fruit production, longitudinal, and transverse diameter of fruit, rind thickness, and vitamin C content. Among saline nutrient solutions, extra addition of 50% K (S3) attenuates the deleterious effects of salt stress on the production variables and vitamin C content. Under salt stress, extra addition of 50% K (S3) and 100% Ca (S6) intensifies the red color of the pulp.

Soil sampling is a fundamental stage for recommending agricultural correctives and fertilizers, estimating the nutritional demands of plants, and consequently maximizing productivity. Therefore, this study aimed to assess the performance of three soil samplers in different management systems in terms of sample quality and operational efficiency. A completely randomized experimental design was used in a factorial scheme. Three samplers and two sampling depths (3 × 2) were used with four replicates. At each sampling location, eight single samples were taken at a varying sampling depth of 0.0-0.2 and 0.2-0.4 m, and the collection time was recorded. Samples were analyzed for chemical attributes and granulometry. Statistically significant differences were observed for specific attributes (organic matter, K, Ca, CEC, pH, and S). In terms of operational efficiency, the hydraulic sampler was more efficient than the other samplers, being three times faster than the combustion drill and six times faster than the manual probe. Thus, it is suitable and reliable for soil sampling purposes.

BioSentinel is the first biological CubeSat designed and developed for deep space. The main objectives of this NASA mission are to assess the effects of deep space radiation on biological systems and to engineer a CubeSat platform that can autonomously support and gather data from model organisms hundreds of thousands of kilometers from Earth. The articles in this special collection describe the extensive optimization of the biological payload system performed in preparation for this long-duration deep space mission. In this study, we briefly introduce BioSentinel and provide a glimpse into its technical and conceptual heritage by detailing the evolution of the science, subsystems, and capabilities of NASA's previous biological CubeSats. This introduction is not intended as an exhaustive review of CubeSat missions, but rather provides insight into the unique optimization parameters, science, and technology of those few that employ biological model systems.

Small satellite technologies, particularly CubeSats, are enabling breakthrough research in space. Over the past 15 years, NASA Ames Research Center has developed and flown half a dozen biological CubeSats in low Earth orbit (LEO) to conduct space biology and astrobiology research investigating the effects of the space environment on microbiological organisms. These studies of the impacts of radiation and reduced gravity on cellular processes include dose-dependent interactions with antimicrobial drugs, measurements of gene expression and signaling, and assessment of radiation damage. BioSentinel, the newest addition to this series, will be the first deep space biological CubeSat, its heliocentric orbit extending far beyond the radiation-shielded environment of low Earth orbit. BioSentinel's 4U biosensing payload, the first living biology space experiment ever conducted beyond the Earth-Moon system, will use a microbial bioassay to assess repair of radiation-induced DNA damage in eukaryotic cells over a duration of 6-12 months. Part of a special collection of articles focused on BioSentinel and its science mission, this article describes the design, development, and testing of the biosensing payload's microfluidics and optical systems, highlighting improvements relative to previous CubeSat life-support and bioanalytical measurement technologies.

Tahiti lime is a species of great economic importance worldwide. In Brazil, production is concentrated in the states of São Paulo and Pará, where it is usually grafted onto the Rangpur lime. This study aimed to analyze the effects of different irrigation depths on the fruit yield, phenology, and gas exchange of Tahiti lime trees grafted onto Swingle citrumelo. Irrigation was performed during the first year at four different irrigation depths in a random block design with five blocks and four treatments to maintain the soil matric potential in the following ranges: T1: below -50 kPa, T2: from -30 to -50 kPa, T3: from -10 to -30 kPa, and T4: above -10 kPa. The flowering, carbon assimilation rate (A), stomatal conductance (gs), transpiration (E), and fruit yield were measured. Fruits were harvested earlier in the most irrigated treatment, T4, and the yield increased from 2.22 to 6.89 kg per plant from T1 to T4. The average fruit weight escalated from 78.6 to 96.1 g from T1 to T4, and carbon assimilation increased from 6.89 to 9.51 μmol CO2m-2s-1 from T1 to T4.

Salinity can have detrimental effects on plant development. To minimize this damage, strategies such as balanced maintenance of plants’ nutritional status have been proposed previously. The objective of this study is to investigate whether the optimization of foliar nitrogen fertilization can promote the growth and photochemical efficiency of purple basil subjected to salt stress. The experiment was performed using a randomized block design with an incomplete 5 × 5 factorial arrangement generated through experimental matrix Central Composite Design with two parameters: salinity of irrigation water at 0.5, 0.81, 2.75, 4.69, and 5.50 dS m-1; and nitrogen doses at 0, 58.58, 200, 341.42, and 400 mg L-1. It was found that an increase in the salinity of irrigation water reduced the growth and photochemical efficiency of purple basil. However, the foliar application of nitrogen at the concentration of 400 mg L-1 attenuated the harmful effects of salinity on both the absolute and relative growth rates of stem diameter, the relative growth of plant height, and chlorophyll A fluorescence. These results showed that foliar nitrogen fertilization is a suitable strategy to help mitigate salt stress in basil plants.

African mahogany (Khaya grandifoliola) is a forest species with excellent wood quality. Due to the increasing demand for viable seeds in forest production programs, the storage capacity of this species must be evaluated. Therefore, this study aimed to determine the appropriate environmental and packaging conditions for the storage of African mahogany seeds. Initially, the water content of the seeds, germination rate, and seedling length were determined in two environments (cold chamber and laboratory), two packages (polyethylene and glass), and three storage periods (72, 144, and 216 d) as well as in additional treatment without storage. The variables analyzed during storage were water content, germination capacity, germination speed index, and seedling length. The experiment was conducted in a completely random design with four repetitions in a split-plot scheme and an additional treatment of 2 × 3 × 2 + 1. African mahogany seeds stored in a cold chamber (6 °C and 72% relative humidity) in a polyethylene packaging maintained their physiological quality for 216 d.

Phosphorus (P) is an essential nutrient for growth and yield of sweet potatoes; in sandy soils, sweet potato yield and quality may be limited by application of low P doses, mainly in degraded areas. The objective of this work was to evaluate the effect of P doses on yield and quality of sweet potato root tubers grown in tropical sandy soils with different initial P availabilities: 23.2 mg dm-3 (high P - crop rotation) and 3.7 mg dm-3 (low P - post degraded pasture). Two experiments were carried out in a randomized block design, with four replicates. The treatments consisted of P doses (0, 22, 44, 88, and 176 kg ha-1) applied to the planting bed. Tuber yield, number and mean weight of tubers, P concentration in leaves and tubers, exported P, as well as the percentage of starch, reducing sugars, total sugars, and sucrose in the tubers were evaluated. P concentration in the soil was evaluated at the end of the experiment. In the area with high P availability (> 20 mg dm-3 - resin), increasing P doses did not increase root tuber yield and decreased root starch concentrations. In the area with low P availability (< 3.7 mg dm-3 - resin), root tuber yield and starch concentration peaked when applying 68 and 33 kg ha-1 of P, respectively. In areas after degraded pasture, with low initial soil P concentration, P fertilization for sweet potato crops should be carried out with a P dose of 68 kg ha-1. In areas with crop rotation and adequate soil P concentration, P fertilization should be carried out to replace the amount of P exported by the harvested root tubers to avoid decreases in soil fertility.