DESEMPENHO DA RÚCULA SOB CONDIÇÕES DE SOMBREAMENTO E NÍVEIS DE SALINIDADE DA ÁGUA DE IRRIGAÇÃO

Arugula is a fast growing vegetative crop and short cycle, of great worldwide acceptance. In Brazil, its production and consumption are prominent in the South, Southeast and Northeast, generating employment and income for family agriculture. The use of saline water in the production of vegetables is one of the main challenges of researchers and rural producers, since saline stress is one of the biggest abiotic problems that causes a decrease in the production and yield of crops. In view of this assertion, the objective was to evaluate the growth of the arugula culture under different levels of saline water. The experiment was conducted in a greenhouse at the Experimental Area of ​​the Agricultural Sciences Center of the Federal University of Alagoas, in the city of  Rio Largo, AL. The treatments consisted of shading (T1 = unshaded, T2 = shaded) and five levels of saline water (0.5, 2.0, 3.5, 5, 0 and 6.5 dS m-1) with four replicates. The variety of arugula used was the APRECIATTA Folha Larga. At 12 DAS the thinning was done leaving only one plant per pot. The following growth indices were evaluated: Plant height, number of leaves, leaf area and shoot dry mass. The plants showed a decrease in normal growth up to 2.0 dS m-1 and with the increase in the electrical conductivity of the water caused a reduction in all growth rates, presenting a varied effect according to the type of environment.A rúcula é uma cultura de rápido crescimento vegetativo e ciclo curto, de grande aceitação mundial. No Brasil sua produção gera emprego e renda à agricultura familiar. O uso de água salina na produção de hortaliças é um dos principais desafios de pesquisadores e produtores rurais, visto que o estresse salino é um dos maiores problemas abióticos que causam diminuição na produção e rendimento de culturas. Em vista dessa afirmativa, objetivou-se avaliar o crescimento da cultura da rúcula sob diferentes níveis de água salina. O experimento foi conduzido em casa de vegetação na área experimental do Centro de Ciências Agrárias da Universidade Federal de Alagoas, na cidade de Rio Largo, AL. Utilizou-se o delineamento inteiramente casulisado em arranjo fatorial 2 x 5. Os tratamentos consistiram de sombreamento (T1 = não sombreado; T2 = sombreado) e cinco níveis de água salina (0,5; 2,0; 3,5; 5,0 e 6,5 dS m-1) com quatro repetições. A variedade de rúcula utilizada foi a APRECIATTA Folha Larga  e aos 12 DAS foi realizado o desbaste deixando apenas uma planta por vaso. Foram avaliados os seguintes índices de crescimento: altura de plantas, número de folhas, área foliar e massa seca da parte aérea. As plantas apresentaram um crescimento normal ate 2,0 dS m-1 e com o aumento da condutividade elétrica da água ocasionou redução em todos os índices de crescimento, apresentando efeito variado de acordo com o tipo de ambiente

WEED CONTROL BY SOLARIZATION AND MULCHING IN COWPEA DEVELOPMENT

Weeds are a serious threat to agriculture because they compete with crops, thereby interfering in production. As such, this study aimed to assess weed control using soil solarization and mulching on the growth and yield of cowpea. A completely randomized design was used, with eight treatments and four repetitions. The treatments consisted of a combination of two management practices, namely soil solarization (with and without) and three mulches (castor bean, rattlepod and spontaneous vegetation), as well as no mulching. Non-solarized soil and without mulch increased the number and dry weight of weeds, while the main stem length of the cowpea plants decreased. Mulching increased the pod length and number of seeds per pod regardless of solarization, as well as shoot dry weight and moisture content. By contrast, root dry weight increased in the absence of mulching, particularly in non-solarized soil. Soil solarization reduces weed infestation in cowpea crops, especially when associated with mulching

EFFICIENCY AND UNIFORMITY OF AN SUBSURFACE DRIP IRRIGATION SYSTEM IN SUGARCANE CROP

Agricultural productivity in irrigated areas depends on several factors, including the design and maintenance of irrigation systems. Excessive or insufficient applications of water affect plant growth and development, hence agricultural productivity. For this reason, the evaluation of the irrigation system is essential to avoid water loss during application. This study aimed to evaluate the efficiency and uniformity of a subsurface drip irrigation system in sugarcane crops in an area of the company Usina Coruripe, Alagoas, Brazil. For data collection, the flow rates were obtained in four points along the lateral line, in the first dripper, in the drippers located at 1/3 and 2/3 of the lateral line length, and in the last dripper of each operational unit of the irrigation project. In each row, four emitters were evaluated, totalizing 16 emitters, using a chronometer, collectors, and a measuring cylinder for data collection. In these emitters, the volume of water was collected for 3 minutes, with three repetitions. Christiansen's uniformity coefficient, distribution uniformity coefficient, statistical uniformity coefficient, Hart's uniformity coefficient, and application efficiency were estimated. The irrigation system was considered excellent for distribution uniformity. The application efficiency was classified as acceptable, with an average value of 88.9%. However, despite the application efficiency being classified as acceptable, periodic evaluations of the system are recommended

Soil management and mulching for weed control in cowpea

More efficient weed control managements can be achieved through different strategies, given that the population of these plants changes according to the system used. This study aimed at assessing solarization methods associated with different mulches for weed control in the cowpea crop. The methods used were soil solarization, with plastic sheeting and with solar collector, associated with the following mulches: castor bean, rattlepod and spontaneous vegetation. Weed phytosociology was calculated by frequency, density and abundance. The most infesting families were Asteraceae, Poaceae and Amaranthaceae. The species with the highest frequency, density and abundance in the treatments without mulching was Cyperus rotundus, while Bidens spp. occurred only in non-solarized soil and without mulching. The largest number of weeds was found in the treatments without mulching in non-solarized soil or soil solarized with plastic sheeting, the latter being less efficient than the solar collector. Mulching inhibits the weed infestation in cowpea crops, irrespective of soil solarization. However, rattlepod as mulch is more efficient in the solarization with plastic sheeting than with a solar collector

MATÉRIA ORGÂNICA COMO ATENUANTE DA SALINIDADE DA ÁGUA DE IRRIGAÇÃO NA CULTURA DO MILHO

The objective of this work was to evaluate the use of organic matter in the development of corn irrigated with saline water. The experiment was carried out at the Agrarian Sciences Center of the Federal University of Alagoas. The experimental design was completely randomized in a 5 x 2 factorial scheme, with four replications, being the treatments: 5 levels of salinity (0.5 (control); 1.5; 3.0; 4.5 and 6.0 dS M-1) with presence and absence of organic matter. Saline solutions were prepared with NaCl and distilled water, and the formula: TSD (G L-1) = 0.64 x CEa was used. At 40 days after emergence, the plants were collected and analyzed for the number of leaves, leaf area, plant height, relative leaf chlorophyll index, shoot dry mass and root system dry mass. It was Found that all the variables studied in the maize crop were affected by the increase in salinity levels and that the soil decreased the effects of salinity when organic matter was added.Objetivou-se, com este trabalho avaliar o uso da matéria orgânica no desenvolvimento do milho irrigado com água salina. O experimento foi conduzido no Centro de Ciências Agrárias da Universidade Federal de Alagoas. O delineamento experimental adotado foi o inteiramente casualizado em esquema fatorial 5 x 2, com quatro repetições, os tratamentos consistiram de diferentes níveis de condutividade elétrica da água CEa, (0,5, 1,5, 3,0, 4,5 e 6,0 dS m-¹) associado a presença e ausência de matéria orgânica no solo. As soluções salinas foram preparadas com NaCl e água destilada, sendo utilizada a fórmula: TSD (g L-1) = 0,64 x CEa. Aos 40 dias após a emergência, as plantas foram coletadas e analisadas quanto ao número de folhas, altura da planta, área foliar, massa seca da parte aérea e massa seca do sistema radicular e o índice relativo de clorofila das folhas. Constatou-se que todas as variáveis estudadas foram afetadas pelo aumento dos níveis de salinidade da água de irrigação e que a adição de matéria orgânica no solo de forma isolada propiciou um melhor desenvolvimento das plantas de milho

Solarização e cobertura morta no solo sobre a infestação de plantas daninhas no feijão-caupi (Vigna unguiculata)

Weed infestation is among the problems of greater interference in agriculture, and therefore has awakened the use of management techniques, as the use of solarization and mulching on the ground, that can mitigate this problem. Thus, was objectified with this work to evaluate the management of solarization and soil mulching on weed infestation in cowpea. The experiment was carried in greenhouse under a completely randomized design with eight treatments, such as: soil solarization (with and without) and three dead cover crops (castor bean, crotalaria and spontaneous vegetation + with four replications. The research was conducted in pots with a capacity of 11 dm3, filled with eight kg of soil, and the sowing was carried out directly in the pots. At 80 days after sowing, the number and total dry mass of weeds in each experimental unit were determined. During this period, the growth and yield characteristics of cowpea were also evaluated. The number and total dry mass of weeds were higher in the uncovered soil, independent of solarization, and the dry mass was higher in the absence of solarization. This weed infestation reduced the length of the main branch, number of leaves, number and length of pods, production of dry mass and amount of water in the aerial part of the cowpea, while increasing the root dry mass. Solarization, when isolated, does not totally suppress the incidence of weeds, but reduces their development. On the other hand, soil cover, independent of type and solarization, reduces the incidence of weeds favoring growth, yield and dry matter production in the aerial part of the cowpea.A infestação de plantas daninhas está entre os problemas de maior interferência na agricultura, e por isso tem despertado a utilização de técnicas de manejo, como o uso de solarização e coberturas vegetais sobre o solo, que podem atenuar essa problemática. Dessa forma, objetivou-se com este trabalho avaliar os manejos de solarização e cobertura morta do solo sobre a infestação de plantas daninhas no cultivo do feijão-caupi. O experimento foi realizado em casa de vegetação sob delineamento inteiramente casualizado com oito tratamentos, como sendo: solarização do solo (com e sem) e três coberturas mortas (mamona, crotalária e vegetação espontânea + ausência de cobertura) com quatro repetições. A pesquisa foi conduzida em vasos com capacidade de 11 dm3, preenchidos com oito kg de solo, e a semeadura realizada diretamente nos vasos. Aos 80 dias após a semeadura, foram determinados o número e a massa seca total de plantas daninhas em cada unidade experimental. Nesse período também foram avaliadas as características de crescimento e rendimento do feijão-caupi. O número e massa seca total de plantas daninhas foram maiores no solo sem cobertura, independente da solarização, sendo a massa seca total maior na ausência da solarização. Essa infestação de plantas daninhas reduziu o comprimento do ramo principal, número de folhas, número e comprimento de vagens, produção de massa seca e quantidade de água na parte aérea do feijão-caupi, enquanto aumentou a massa seca radicular. A solarização quando isolada não suprime totalmente a incidência de plantas daninhas, mas reduz o desenvolvimento destas. Por outro lado, a cobertura do solo, independente do tipo e da solarização, reduz a incidência de plantas daninhas favorecendo o crescimento, rendimento e produção de massa seca na parte aérea do feijão-caupi

DETERMINANTS OF INTENT TO PURCHASE ORGANIC PRODUCTS TO IMPROVE QUALITY OF LIFE

Concerns about food quality and safety have grown as cases of disease and food-related scandals increase. To mitigate this problem, organic products have been a solution, as their certification is provided through processes that are less harmful to the environment and consumer health. To understand the main motivations of consumers of organic products, the objective of this study is to demonstrate whether the statistical values of the predictor variables (health concern, signaling trust, and attitude) confirm their purchase intention (dependent variable). To carry out this research, the survey method was used, applying a questionnaire with open and closed questions to 288 respondents, supporting the elaboration of a structural model based on four hypotheses, which were confirmed through statistical calculations. As for the contribution, this work supports the alignment of expectations and preferences of the members of the production chain of organic products

Germinação e crescimento inicial de girassol (Helianthus annuus L.) sob diferentes substratos submetidos a estresse salino / Germination and initial growth of sunflower (Helianthus annuus L.) under different substrates submitted to saline stress

O girassol (Helianthus annuus L.) é uma espécie de grande importância agrícola, dentre as plantas de ciclo curto, apresenta características agronômicas importantes, como maior resistência à seca, ao frio e ao calor, o que lhe confere grande potencialidade de cultivo em diferentes regiões do país. Entre outros usos, suas sementes podem ser utilizadas para fabricação de ração animal, extração de óleo de alta qualidade para consumo humano e como matéria-prima para a produção de biodiesel. O cultivo em substratos demonstra um avanço na produção de mudas de várias espécies de interesse agronômico, por fornecer mais nutrientes, atenuar afeitos nocivos e consequentemente proporcionar melhores condições para o desenvolvimento da planta. A utilização de água de baixa qualidade é um dos fatores limitantes na produção de várias culturas, sendo o Nordeste uma das regiões mais prejudicadas por esse fator. O presente trabalho teve como objetivo avaliar o desenvolvimento inicial de plântulas de girassol em diferentes substratos irrigados com água salina. O experimento foi conduzido em viveiro telado da Unidade de Execução de Pesquisa da Embrapa Tabuleiros Costeiros, situada no Centro de Ciências Agrárias da Universidade Federal de Alagoas, no Município de Rio Largo. O delineamento experimental foi o inteiramente casualizado em esquema fatorial 5x3 com cinco dosagens salinas (0,0; 2,5; 3,5; 4,5 e 5,5 dSm-1), três tipos de substratos (terra preta, torta de filtro e substrato industrial) e quatro repetições. Foram avaliadas as seguintes variáveis: porcentagem de emergência das plântulas, índice de velocidade emergência, número de folhas, altura das plântulas, diâmetro do caule, massa úmida e massa seca total da plântula. Constatou-se que os níveis mais elevados de salinidade do solo reduziram o desenvolvimento das plântulas de girassol, havendo interação para o fator substrato, sendo o Terra Preta o melhor avaliado

Pyruvate supplementation in cotton under water restriction varying the phenological phases

Cotton is one of the largest agricultural commodities that generate various sources of foreign exchange and employment worldwide. However, water deficiency is an environmental factor that limits the production of this crop, especially in semi-arid regions. We evaluated pyruvate supplementation to mitigate the effects of water stress on colored cotton. Experiments were conducted in a greenhouse. We studied two forms of pyruvate supplementation (SP1- via seed and foliar and SP2- only via foliar); three conditions of irrigation management of the plants: water restriction in the vegetative phase (VE), flowering (FL), and vegetative and flowering (VE/FL); and additional treatment (total irrigation throughout the crop cycle and without pyruvate supplementation). The experimental design included a randomized block in a 2 × 3 + 1 factorial scheme. The factors resulted in seven treatments with three replications, with a total of 21 experimental units. Gas exchange, enzyme activity, and production of components were evaluated. Water restriction in the vegetative phase does not cause losses in BRS Jade cotton when supplemented with pyruvate. However, in the flowering and vegetative phases plus flowering, it reduces gas exchange and production components and increases the activity of antioxidant enzymes in relation to plants under full irrigation. Supplementation with pyruvate via seed plus foliar (SP1) was better for BRS Jade cotton grown under water restriction