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The identification of promising commercial varieties for irrigated crops in semiarid conditions based on characters of interest to sugarcane agro-industries is important, considering the search for high sugarcane yields to obtain sustainable crops. Thus, the objective of this work was to evaluate production components of agroindustrial interest of different sugarcane varieties grown under subsurface drip irrigation in the Semiarid region of Brazil, during two crop cycles. A randomized block experimental design was used, in an 8×2 factorial arrangement (varieties and cycles) with three replications. The sugarcane juice quality, sugar yield, and culm yield were evaluated in each cycle. Gross sugar percentage, sugarcane culm yield, juice apparent sucrose content, and juice purity were affected by the crop cycles. Soluble solids content presented strong significant correlation with most variables of agroindustrial interest. The path coefficient analysis showed that juice apparent sucrose content was the explanatory character with higher direct effect on soluble solids and that this variable presented high indirect effects on most explanatory variables. The sugarcane varieties RB72454 and Q124 are recommended for production managements with drip irrigation under semiarid conditions. Soluble solids content can be used as an alternative for direct selection of varieties with higher sugar yields in different cycles.

Rising temperature affects agricultural production, causing food insecurity. Thus, the objective of this study was to evaluate how increased temperature influences pollen viability, photosynthetic and enzymatic responses, and their consequences on the final yield of cowpea cultivars. The cultivars BRS Acauã, BRS Guariba, BRS Gurguéia, and BRS Pajeú were used, kept in growth chambers under two temperature regimes: 24.8–30.8–37.8 °C and 20–26–33 °C. The cultivars BRS Acauã, BRS Guariba, and BRS Pajeú showed prolonged flowering and greater flower abortion, at 23.58%, 34.71%, and 25.55%, respectively, under an increase of 4.8 °C in temperature. This increase also reduced the viability of BRS Acauã and BRS Pajeú pollen by 34 and 7%, respectively. Heating increased stomatal opening and transpiration but reduced chlorophyll content. The enzymatic response varied according to cultivars and temperature. Changes in photosynthetic and enzymatic activities contribute to reducing pollen viability and productivity. BRS Acauã was the most affected, with an 82% reduction in the number of seeds and a 70% reduction in production. BRS Gurguéia maintained its production, even with an increase of 4.8 °C, and can be selected as a cultivar with the potential to tolerate high temperatures as it maintained pollen viability, with less flower abortion, with the synchrony of physiological and biochemical responses and, consequently, greater production.

Cowpea planting season is crucial for high yield and should comprise the period of the year that warrants the best climatic conditions for cowpea cultivation. Thus, the objective of this study was to evaluate the influence of water availability and temperature on the performance of cowpea cultivars. A greenhouse experiment was conducted using a 4 × 2 × 5 factorial arrangement, with four replications. Factors included four levels of soil moisture (25, 50, 75, and 100% of water holding capacity), two growing seasons (mild and hot), and five cowpea cultivars (Carijó, Itaim, Pujante, Rouxinol, and Tapahium). The number of pods and seeds per plant, seed production, water use efficiency, shoot dry mass, root dry mass, and physiological parameters were evaluated. Seed production was higher during the mild season than during the hot season and increased linearly with increasing soil water availability. Photosynthetic activity and transpiration were higher during the hot season than during the mild season, with their reduction under a water availability of 25% regardless of the growing season. Total chlorophyll content decreased with excess water. Regardless of water availability, temperature was the most limiting climatic factor for cowpea performance. Cultivars Carijó, Itaim, and Tapahium exhibited a lower reduction in productive potential when grown in the hot season.

Considering that changes in climatic parameters directly interfere in crop yields, this study aimed to evaluate the impact of changes in carbon dioxide concentrations, temperature and soil water availability on production, water-use efficiency and onion (Allium cepa L. cv. IPA 11) quality. Four levels of soil water availability (40, 60, 80 and 100 %) and two concentrations of atmospheric CO2 (770 and 390 ppm) were evaluated in three experiments with different temperature regimes (18-24-30, 22-28-34 and 26-32-38 ºC), in Phytotron growth chambers. The water-use efficiency, bulb diameter and weight, shoot dry weight, pulp firmness, soluble solids content, pH and titratable acidity were also evaluated. The increase in temperature reduces the production, and a higher soil water availability increases the production of IPA 11 onion bulbs. The temperature regime of 18-24-30 ºC and the water availability of 76.72 % provide the best water-use efficiency for the onion crop.

Sisal is widely produced in the semi-arid region of Bahia State, Brazil, and an important source of economic income for rainfed agriculture. Thus, the objective of the study was to analyze and classify the historical series of rainfall in relation to its profiles and the trends related to rainfall and sisal production in two mesoregions and four meteorological stations. Pluviometric characterization and water balance were carried out; data were organized to fit Gumbel's model and classified by the Quantis technique; then, the trend was determined through the non-parametric test of Mann-Kendall. Average rainfalls between 565.1 and 687.3 mm were obtained, very dry years with rainfalls between 370.3 and 445.7 mm and very rainy years, between 748.3 and 962.5 mm, with a trend of reduction of productivity in years classified as dry and very dry and vice versa.

The objective was to perform a comparative study of the meteorological elements data that most cause changes in the reference Evapotranspiration (ETo, mm) and its own value, of automatic weather stations AWS and conventional weather stations CWS of the Sertão and Agreste regions of Pernambuco State. The ETo was calculated on a daily scale using the standard method proposed by the Food and Agriculture Organization (FAO), Penman-Monteith (FAO-56). The ETo information obtained from AWS data can be used to update the weather database of stations, since there is a good relationship between the ETo data obtained from CWS and AWS, statistically determined by the Willmott's concordance index (d > 0.7). The observed variations in the weather elements: air temperature, relative humidity, wind speed, and global solar radiation have not caused significant changes in the ETo calculation.

ABSTRACT Water deficit and high temperatures are abiotic factors that most limit plant growth and development. However, its effects depend on crop development stage and on stress duration and intensity. Thus, the objective of was to evaluate the development of cowpea subjected to water restriction in different phenological stages and to increase in air temperature. The experiment was conducted with the cultivar ‘Carijó’, in growth chambers, in a 4 x 3 x 2 factorial arrangement, corresponding to levels of water availability (25, 50, 75, and 100%,), phenological stages (vegetative, flowering and pod filling) and temperature regimes (T°1: 20-26-33 °C e T°2: 24.8-30.8-37.8 °C), respectively. Reduction of water availability in the vegetative and flowering stages caused decrease in grain production. The percentage of aborted flowers was higher in plants maintained under an increased temperature of +4.8 °C, with consequent reduction in grain production. Higher water availability values favored shoot and root dry mass production. Increase of 4.8 °C did not affect shoot and root dry mass but reduced water use efficiency by about 83%. The highest enzymatic activities of CAT, GPX and SOD were found in plants subjected to the temperature of +4.8 °C. Only APX showed lower enzymatic activity with increasing temperature. The cv. ‘Carijó’ is more sensitive to the 4.8 °C increase in air temperature than to water deficits.

This work presents part of the results of a master's thesis developed at the Vinícius de Moraes Rural Municipal School in Juína-MT, Brazil. The school is located on the left bank of the Juruena River, opposite bank where some villages of the Rikbaktsa ethnic group are located. In village schools, teachers are mostly indigenous and follow a specific curriculum guided by national legislation. Even so, some Rikbaktsa parents prefer studies to take place in the rural school. The research asks: Why do some parents of Rikbaktsa students look for non-indigenous schools for their children to study? The purpose of the investigation was to identify the reasons why Rikbaktsa parents chose a non-indigenous school for the education of their children. Data were collected through semi-structured interviews and organized using content analysis. The results show that students' parents understand that non-indigenous school helps young Rikbaktsa students to understand non-indigenous society and better prepares them for a profession. According to the analysis, professionalization by the study is a safe way through which they can have a financial income to meet their future needs and also, with new knowledge, improve the life in their indigenous community.

The objective of this work was to evaluate the biomass production and antioxidant enzymatic system activity of irrigated forage sorghum with saline aquaculture effluent under different leaching fractions. The experiment was conducted in the Caatinga Experimental Field of the Embrapa Semiarido, in Petrolina, State of Pernambuco, Brazil. The experimental design was a complete randomized block in a split-plot arrangement with four replications, consisting of three forage sorghum varieties (Volumax, F305 and Sudan) and four leaching fractions (0, 5, 10 and 15%). The vegetal materials were collected when the plants were at the soft-dough stage. The biomass production and activity of the enzymes superoxide dismutase, catalase and ascorbate peroxidase were evaluated. Irrigation with saline aquaculture effluent with leaching fraction of 15% results in low salinity level in the root zone and higher biomass production of forage sorghum Sudan and F305, in semiarid conditions. The antioxidant system was activated in the three sorghum varieties to prevent accumulation of reactive oxygen species, with the synchrony between the enzymes superoxide dismutase and catalase resulting in a better productive response of the varieties Sudan and F305.

The high luminosity rates and high annual average temperatures of the Brazilian semiarid region, combined with the use of irrigation and adaptability of the sunflower crop to local climate, favor increased achene yield due to acceleration of morphophysiological processes. The objective of this work was to evaluate the morphophysiological and productive characteristics of sunflower varieties grown under drip irrigation in the Sub-Mid São Francisco River Valley. The experiment was conducted in the Experimental Field of the Brazilian Agricultural Research Corporation (Embrapa Semiarid), in Petrolina, State of Pernambuco, Brazil, in a randomized block design, with 21 sunflower varieties and four replications. The variables evaluated were flowering time, plant height, number of live leaves, stem and capitulum diameter, number of lodged and broken plants, stem curvature, relative chlorophyll index, photosynthesis, stomatal conductance, transpiration, average leaf temperature, 1000-achene weight and achene yield of the sunflower varieties. The treatments presented flowering time of 43 to 59 days after sowing, plant height of 1.0 to 1.4 m, capitulum diameter of 0.154 to 0.221 m, chlorophyll content of 30.8 to 33.98 Spad units and 1000-achene weight of 35.61 to 80.30 g. The sunflower varieties V7 and V8 stood out, with achene yields above 2,960 kg ha-1 and low number of lodged and broken plants, indicating a greater adaptability irrigation crops in the Sub-Mid São Francisco River Valley.

Sugarcane is one of the most affected crops by water scarcity. The efficient use of the irrigation water is an alternative to minimize this problem. The objective of this work was to evaluate biometric parameters, yield, and technological quality of sugarcane plants subjected to different controlled water deficit regimes in the sub-middle São Francisco Valley, Brazil. The experiment was conducted in a randomized block design, in two crop cycles, with three replications, with ten treatments consisted of three controlled water deficits (15%, 30%, and 45% of the crop evapotranspiration - ETc), applied at three development stages of the plant - sprouting and tillering (Stage I), grand growth (Stage II), and maturation (Stage III) - and a control with 100% of the ETc throughout the entire crop cycle. The controlled water deficit did not affect the technological quality of the sugarcane in any development stage. The sugarcane yield was higher when using a controlled water deficit of 30% of ETc in the sprouting and tillering stages of the plants. The water deficit of 15% of ETc is recommended for the grand growth, or maturation stages of the sugarcane plants for a greater water use efficiency of the production system.

Growing in a saline environment causes changes in important physiological processes that are directly related to plant growth and development. In this study we evaluated the effect of salinity on transpiration of sorghum plants in semi-arid conditions and found that the highest rates of transpiration were observed in the hottest hours of the day, between 10 a.m. and 3 p.m., with plants subjected to the saline environment having their transpiration reduced by up to 70% when compared to the non-saline environment. This behavior can be reflected in reductions in plant growth and development due to reduced water absorption by the roots, consequently causing an imbalance of nutrients in the plant due to low absorption rate and competition between nutrients and salts in the preferred routes of absorption in the roots.

O presente trabalho objetivou caracterizar o perfil da precipitação do município de Cruz das Almas-BA através da técnica de Quantis e realizar o balanço hídrico dos distintos regimes hídricos identificados na região. Para isto, foram utilizados dados de precipitação e temperatura do ar obtidos numa estação meteorológica convencional (OMM: 83222) localizada no município de Cruz das Almas-BA, Recôncavo Baiano. A partir dos dados de precipitação anual, aplicou-se a técnica de Quantis, classificando os anos de acordo com o índice pluviométrico anual como muito seco, seco, normal, chuvoso e muito chuvoso. Em seguida, os anos foram agrupados de acordo com o regime pluviométrico e, assim, realizado o balanço hídrico pelo método de Thornthwaite & Mather (1955), utilizando o valor de 100 mm como capacidade de água disponível. O estudo realizado demonstra a importância do estudo da precipitação para se obter um bom planejamento agrícola. O município estudado apresenta uma média anual de precipitação de 1131,17 mm, apresentando período de chuva bem definido, compreendendo os meses de março a agosto. A prática da irrigação se apresenta como alternativa viável para produção agrícola nos períodos de deficiência hídrica, principalmente nos anos classificados como secos e muito secos.

Objetivou-se com este trabalho determinar equações que possibilitem estimar a área foliar de genótipos de mandioca a partir de medidas biométricas das folhas. Foram coletadas folhas de 17 genótipos de mandioca e mensurados em cada unidade o comprimento, a largura do lóbulo central e a área foliar real. Os genótipos foram agrupados por meio do método de análise multivariada UPGMA, utilizando-se a razão entre o comprimento do lóbulo central com a largura do mesmo (C / L). Após o agrupamento foi realizado o teste de correlação de Pearson entre as medidas biométricas e a área foliar real. Foram testados modelos de equação linear e potencial para os grupos encontrados na análise de agrupamentos. As variáveis biométricas que apresentaram maior correlação com a área foliar foram o produto do comprimento e a largura do lóbulo, e o comprimento do lóbulo central. Quatro diferentes grupos foram encontrados, nos quais os modelos de equação linear se ajustaram melhor quando se aplica o produto entre o comprimento e a largura do lóbulo central e os potenciais quando se usa o comprimento do lóbulo central.

El autor propone los medios más eficaces para realizar el trabajo de veedurías en los observatorios y narra las experiencias de Argentina en cuanto a los espacios de análisis y discusión acerca del accionar de los medios públicos y privados y acerca de cómo la legislación es desconocida por la mayoría de periodistas que se encuentran en la indefensión.

Rising temperature affects agricultural production, causing food insecurity. Thus, the objective of this study was to evaluate how increased temperature influences pollen viability, photosynthetic and enzymatic responses, and their consequences on the final yield of cowpea cultivars. The cultivars BRS Acauã, BRS Guariba, BRS Gurguéia, and BRS Pajeú were used, kept in growth chambers under two temperature regimes: 24.8–30.8–37.8 °C and 20–26–33 °C. The cultivars BRS Acauã, BRS Guariba, and BRS Pajeú showed prolonged flowering and greater flower abortion, at 23.58%, 34.71%, and 25.55%, respectively, under an increase of 4.8 °C in temperature. This increase also reduced the viability of BRS Acauã and BRS Pajeú pollen by 34 and 7%, respectively. Heating increased stomatal opening and transpiration but reduced chlorophyll content. The enzymatic response varied according to cultivars and temperature. Changes in photosynthetic and enzymatic activities contribute to reducing pollen viability and productivity. BRS Acauã was the most affected, with an 82% reduction in the number of seeds and a 70% reduction in production. BRS Gurguéia maintained its production, even with an increase of 4.8 °C, and can be selected as a cultivar with the potential to tolerate high temperatures as it maintained pollen viability, with less flower abortion, with the synchrony of physiological and biochemical responses and, consequently, greater production. [ABSTRACT FROM AUTHOR]

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