O semiárido do nordeste brasileiro é caracterizado pelas irregularidades pluviométricas e altas temperaturas. Essas características se tornam um fator limitante para a produção agrícola da região, reduzindo a disponibilidade de água, sobretudo que atendam parâmetros ideais para a irrigação. Dessa forma, objetivou-se com este trabalho avaliar a estatística multivariada como ferramenta para analisar a qualidade de água residuária utilizada por agricultores na região semiárida. A coleta dos dados foi realizada em três cidades da região semiárida em dois períodos distintos. Foram realizadas análises laboratoriais dos parâmetros químicos, físicos e microbiológicos e sua classificação quanto à indicação para uso de água para irrigação. Realizou-se a análise de componentes principais para averiguar os parâmetros que exerceram maiores influencias na qualidade das águas nas cidades estudadas nos dois períodos e análise de agrupamento hierárquico para averiguar a familiaridade dos parâmetros. A qualidade da água superficial foi influenciada pelo local de sua proveniência, como as subterrâneas, que foram influenciadas pela composição química do solo e pela utilização de fossas ineficientes. A superficial foi influenciada, sobretudo por esgotos e pela poluição de indústrias e veículos. As águas também foram influenciadas pelo volume de precipitação, tendo uma menor qualidade quando se apresentou maior volume de chuva.

The objectives were to analyze the water and nitrogen use efficiency by forage palm in different irrigation depths with saline water and nitrogen fertilization levels in the Brazilian semi-arid region. The experiment was conducted under field condition during one year of cultivation (360 days). The experimental design was a complete randomized block and 5 x 5 factorial scheme with five irrigation depths (125, 100, 75, and 25% of ET0) and five levels of nitrogen fertilization (0, 150, 300, 450 and 600 kg ha-1 of N) and three replicates. Irrigation and acceptable nitrogen fertilization resulted in a good water and fertilization management. Water and nitrogen use efficiency of forage palm were higher, when water depths and the nitrogen levels supplied to the soil were increased. The 125% ET0 depth showed a higher efficiency of water and nitrogen use in the forage palm during 360 days of study. In conditions of low nitrogen supply, the efficiency of nitrogen use is directly and indirectly associated with the fresh mass yield; while under high supply, the efficiency of the use of nitrogen is more effective. The use of irrigation and nitrogen fertilization in the semi-arid region is recommended to obtain higher productivity of water and nitrogen from the forage palm.

The use of salt stress attenuators is considered an important tool to minimize the deleterious effects of salts. However, its application to chives (Allium schoenoprasum L.) has not been studied. This study aimed to evaluate the induction of salt stress tolerance in chives plants in relation to growth and enzymatic reactions, when subjected to different salinity levels of the nutrient solution, after acclimation of seeds with hydrogen peroxide (H2O2) for 24 h. The experiment was conducted in a greenhouse, where chives seeds were acclimated by H2O2 at concentrations of 0.0, 0.15, 0.30, 0.45 and 0.60 mmol. After germination, the plants were cultivated in hydroponic system with electrical conductivities of 1.0, 2.0, 3.0, 4.0 and 5.0 dS m -1 . Plant height, length and number of leaves, H2O2 content, malondialdehyde and catalase (CAT) activity were evaluated in chives plants. The increase in the salinity of the nutrient solution up to 5 dS m -1 reduced by 5.88%, 17% and 9.63% plant height, leaf length and number of leaves, respectively. It was observed that the acclimation of chives seeds with H2O2 at 0.45 mmol g -1 fresh mass in plants that were cultivated in nutrient solution of 3.73 dS m -1 led to maximum CAT activity, minimizing the deleterious effects of nutrient solution salinity on plant growth.

Objetivou-se estudar o tratamento pré-germinativo de sementes de cebolinha com diferentes concentrações de peróxido de hidrogênio. O experimento foi conduzido no laboratório de fisiologia vegetal pertencente à Universidade Federal de Campina Grande (UFCG). Os tratamentos foram distribuídos em delineamento inteiramente casualizado simples com cinco concentrações de peróxido de hidrogênio (0,0; 0,015; 0,030; 0,045 e 0,060 mM) e quatro repetições, totalizando 20 unidades experimentais. As sementes foram embebidas em recipientes de cor escura por 24 horas em temperatura ambiente. Adotou-se o método de germinação em substrato (papel germitest) umedecido com as soluções, a temperatura de 25 °C. Foi avaliado o sistema produtivo que incluiu o número de plântulas germinadas (NPG), comprimento das plântulas (CP), massa fresca das plântulas (MFP), massa seca das plântulas (MSP), porcentagens de germinação (%G), índice de velocidade de germinação (IVG), tempo médio de germinação (TMG) e a velocidade média de germinação (VMG). As avaliações foram realizadas diariamente durante 12 dias após a instalação do teste. O pré-tratamento das sementes com peróxido de hidrogênio influenciou positivamente no crescimento das plântulas de cebolinha. Diante dos resultados, recomenda-se o pré-tratamento das sementes de cebolinha com 0,036 mM de peróxido de hidrogênio.

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The use of water of high electrical conductivity has become common in hydroponic systems, especially in regions with water scarcity. However, the use of inferior-quality water can affect crop yields. In this scenario, some studies have tested the use of chemical conditioning agents such as hydrogen peroxide to minimize the negative effects of stress on plants. From this perspective, this study aimed to evaluate the action of priming with hydrogen peroxide as a salt stress attenuator on the nutrient solution uptake and productivity of chives in a hydroponic system. The study was conducted in a protected environment with a randomized block design with a split-plot arrangement. The treatments consisted of a main plot consisting of the electrical conductivity of the nutrient solution (1.0, 2.0, 3.0, 4.0, and 5.0 dSm−1) and a subplot with five hydrogen peroxide concentrations (0.0, 0.15, 0.30, 0.45, and 0.60 mM). The increase in the electrical conductivity of the nutrient solution reduced bulb length, the solution volume applied, water uptake, total fresh mass, and the solution use efficiency by plants. Throughout the cultivation cycle in the hydroponic system, the consumption of nutrient solution was 459 mm lost by evapotranspiration. Acclimation with 0.60 mM hydrogen peroxide associated with 1 dSm−1 of electrical conductivity of the nutrient solution favors bulb diameter in chives. The increase in electrical conductivity compromises the productive yield of chives.

Food and nutrition security is about promoting rights to access sufficient, quality food without compromising other essential needs. The measures of social distancing, the paralysis of non-essential economic activities imposed to control the pandemic of COVID-19 caused disruptions in food production and supply chains worldwide. The study aimed to assess the food and nutrition security status of households in the Republic of Benin and also the socioeconomic situation during the pandemic. The results showed that the COVID-19 pandemic increased the levels of poverty and food insecurity in Benin. Overall more than 50% of the participants were living on only one minimum wage or less and more than 50% were living in acute food insecurity including families with children. The central region of the country was the most affected by food insecurity followed by the northern region. There was a lack or low intervention of regional, economic and social policies to maintain jobs and guarantee food for the affected families. More governmental or non-governmental policies are needed to ensure food and nutritional security for low-income families.