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ABSTRACT Pitaya (Hylocereus undatus and H. costaricensis) is found in the group of exotic fruits and its cultivation in Brazil is expanding, especially in the semi-arid region of the Northeast. In this region, the problems of water quantity and quality usually cause environmental stresses which limit the survival of plants, especially during germination and seedling establishment. Thus, the objective was to evaluate the mitigating action of pre-germination treatments in pitaya seeds under salt stress. The experiment was conducted in a completely randomized design, in a 2 × 6 factorial scheme, corresponding to two species of pitaya (H. undatus and H. costaricensis) and six pre-germination treatments (T1 = 0.0 MPa (control); T2 = salt stress (-0.4 MPa); T3 = hydropriming + salt stress; T4 = gibberellic acid + salt stress; T5 = salicylic acid + salt stress; T6 = thiamethoxam + salt stress). After 20 days of sowing, germination, germination speed index, shoot length, primary root length, total dry mass, total soluble sugars and total free amino acids were analyzed. H. costaricensis was more tolerant to salinity than H. undatus. Salicylic acid stimulated the germination and growth of H. undatus, besides increasing the soluble sugar content in H. costaricensis. Seed hydropriming attenuated salt stress during germination of H. undatus and favored dry mass gain. Gibberellic acid stimulated the germination of H. undatus and the growth of H. undatus and H. costaricensis seedlings, in addition to increasing the levels of soluble sugars in H. undatus.

Saline stress impairs germination and initial plant growth. However, discontinuous hydration cycles induce osmotic tolerance in seeds and can improve the response of maize seeds to saline stress. The objective of this study was to evaluate the action of discontinuous hydration cycles with different salt stress tolerance elicitors on germination, growth, and osmotic adjustment of maize cultivars. Maize seeds of BR 206 and BRS 5037 Cruzeta cultivars were subjected to the following treatments: 0.0 mmol of NaCl (control), 250 mmol of NaCl (salt stress), salt stress + three discontinuous hydration cycles (DHCs) of seeds in water, salt stress + DHCs with gibberellic acid, salt stress + DHCs with hydrogen peroxide, salt stress + DHCs with salicylic acid, and salt stress + DHCs with ascorbic acid. Salt stress reduced the germination, growth, and biomass accumulation in maize seedlings—the BR 206 cultivar outperformed BRS 5037 Cruzeta. Discontinuous hydration cycles with water failed to improve the salt stress tolerance of maize seeds. However, discontinuous hydration cycles with gibberellic acid, hydrogen peroxide, and salicylic acid promoted salt stress tolerance in maize due to increased synthesis of osmoprotectants. Our results revealed salicylic acid is appropriate for discontinuous hydration cycles in maize seeds.

ABSTRACT Information on the effects of climate conditions on the survival of species grown in semi-arid regions is essential and at the same time scarce, especially regarding rustic species such as West Indian gherkin (Cucumis anguria L.). Thus, this study aimed to evaluate germination, growth and biochemical alterations in C. anguria seeds under water stress and different temperature regimes. The experimental design was completely randomized, in 5 x 5 factorial scheme, composed of five osmotic potentials (0.0; -0.1; -0.2; -0.3 and -0.4 MPa) and four temperatures (20; 25; 30 °C and alternating temperatures of 20-30 ºC), with each treatment composed of four replicates of 50 seeds. The seeds were sown on paper towel (Germitest®) and germinated in Biochemical Oxygen Demand (B.O.D.) germinators, under 8-h photoperiod. Germination percentage, germination speed index, mean time of germination, seedling length and contents of chlorophylls, carotenoids, proline, free amino acids and free sugars were determined along the experiment. Decrease in osmotic potential reduced germination, growth and contents of chloroplast pigments of C. anguria seedlings, but was more drastic at levels lower than -0.2 MPa. Low temperatures intensify the effects of water stress on the germination of C. anguria seeds. The synthesis of protecting osmolytes increased in C. anguria seedlings but these components did not promote efficient osmotic adjustment in their initial development stage.

The economically profitable production of crops is related, among other factors, to seed quality, the production system, and the water used in irrigation or preparation of nutrient solutions. Therefore, the objective was to evaluate the phenology, production, and vigor of seeds of mini watermelons grown in saline nutrient solution and different substrates. In the fruit and seed production phase, the experiment occurred in a greenhouse with five electrical conductivities of water for nutrient solution preparation, ECw (0.5, 2.4, 4.0, 5.5, and 6.9 dS m−1), and two growing substrates (coconut fiber and sand). We evaluated the physiological quality of seeds previously produced under the five electrical conductivities of water and two substrates. High salinities for the hydroponic cultivation of the mini watermelon cultivar ‘Sugar Baby’ accelerated fruit maturation and crop cycle, decreasing fruit size. However, in both substrates, the seed production of mini watermelons, seed viability, and seed vigor occurred adequately with a reject brine of 6.9 dS m−1 in the hydroponic nutrient solution. The seed production of ‘Sugar Baby’ mini watermelons using reject brine in a hydroponic system with coconut fiber and sand substrates is viable in regions with water limitations.

Salvia hispanica L. is an alternative crop cultivated by farmers who want to diversify their production. However, this species is sensitive to salinity, which affects its germination negatively. Seed priming with different attenuators is a technique with potential to mitigate the effects of salt stress. Thus, the objective of this study was to evaluate the effect of seed priming with the use of different attenuators on the germination, growth, and organic solute accumulation of S. hispanica seedlings under salt stress. The experimental design was completely randomized, with treatments distributed in a 4 × 5 factorial scheme, corresponding to four seed priming treatments and five osmotic potentials, with four replicates of 50 seeds in each treatment. The seed treatments consisted of presoaking seeds for 4h in salicylic acid, gibberellic acid, and distilled water and the control treatment, which did not involve soaking. These seeds were germinated at osmotic potentials of 0.0, -0.1, -0.2, -0.3, and -0.4 MPa, using NaCl as an osmotic agent to simulate the different salinity levels. Among all the treatments implemented, S. hispanica seed priming with salicylic acid was the most efficient in mitigating the salt stress effects.

Abstract: Melon is a vegetable crop of food and nutritional importance whose cultivation is growing worldwide. In this sense, investments in technologies are necessary, especially regarding the quality of seeds used in the establishment of new areas. This study aimed to verify the effectiveness of the Automated Seed Vigor Analysis System (Vigor-S) in the evaluation of the physiological potential of melon seeds. Eight seed lots (four lots of the hybrid Supreme and four of the hybrid Premier) were used. The physiological potential of the seeds was evaluated through tests indicated for analyzing the quality of melon seeds associated with the image analysis by using the software Vigor-S, which included the analysis of seedlings from the germination test and accelerated aging in saturated NaCl solution. The experiment was conducted in a completely randomized design, with five replications. The results indicated the effectiveness of Vigor-S, especially when it was used associated with the accelerated aging test in saturated NaCl solution, with results similar to those obtained in traditional vigor tests. Thus, the Automated Seed Vigor Analysis System (Vigor-S) was effective in evaluating the physiological potential of melon seeds.

Water availability and substrate type are essential factors in seed germination tests, influencing imbibition and seedling development. The objective of this study was to evaluate the influence of two substrates and different water volumes on the germination and vigor of chia seeds. The experimental design was completely randomized in a 2 x 6 factorial scheme, which consisted of two substrates, paper towel (Germitest®) and blotting paper, soaked with six water volumes equivalent to 1.5, 2.0, 2.5, 3.0, 3.5, and 4.0 times their dry weight, in four replicates of 50 seeds each. Germination percentage, mean time of germination, shoot length, radicle length, shoot dry matter, radicle dry matter, total dry matter (seedling), and root/shoot ratio were evaluated. Based on our results, germination tests for seeds of chia should be conducted using blotting paper (on paper) as substrate, with a water volume of 2.5 to 4.0 times its dry weight. Chia seedlings grown on blotting paper showed greater growth and dry matter accumulation compared to those grown on paper towel.

ABSTRACT The tetrazolium test is one of the promising alternatives to determine the viability of dormant, recalcitrant and slow-germinating seeds. The objective of this study was to adapt the tetrazolium test methodology to estimate the viability and vigor of Piptadenia stipulacea (Benth.) Ducke seeds. For this, a sample of seeds was classified into three sublots using round sieves, corresponding to six, five and four millimeters in diameter, respectively. Moisture content, imbibition curve, germination, emergence, germination and emergence speed indices, mean germination time and seedling emergence were initially evaluated. The second stage was conducted using a completely randomized experimental design, in 3 x 9 factorial scheme, corresponding to three sublots and nine combinations between concentrations and time of immersion in tetrazolium salt (0.05%/2 h; 0.05%/4 h; 0.05%/6 h; 0.075%/2 h; 0.075%/4 h; 0.075%/6 h; 0.1%/2 h; 0.1%/4 h; 0.1%/6 h), totaling twenty-seven treatments with four replicates of 25 seeds, evaluated separately at 35 and 40 °C. For each treatment, the seeds were divided into four classes: viable and vigorous seeds (class I), viable and non-vigorous (class II), unviable (class III) and dead (class IV). The period of 8 h of pre-imbibition and 4 h of staining in tetrazolium solution at 0.075%, under 35 or 40 °C, is adequate to estimate the viability and vigor of P. stipulacea seeds.

Objetivou-se com este trabalho avaliar o efeito da salinidade de água e proporções fósforo/nitrogênio sobre o crescimento, composição foliar de macronutrientes e sódio e a produção da aceroleira. A pesquisa foi realizada em ambiente protegido, em lisímetros preenchidos com Neossolo Regolítico de textura franco-argilosa e baixo teor inicial de fósforo. O experimento foi desenvolvido em ambiente protegido, em lisímetros com Neossolo Regolítico; o delineamento foi o de blocos casualizados com os tratamentos arranjados em esquema fatorial 5 x 4, referente aos níveis níveis de condutividade elétrica da água de irrigação - CEa (0,6; 1,4; 2,2; 3,0 e 3,8 dS m-1) e quatro proporções percentuais de fósforo e nitrogênio P/N (100:100; 140:100; 100:140 e 140:140% P/N), com três repetições. As doses de fósforo e nitrogênio correspondentes a 100% da recomendação de adubação fosfatada e nitrogenada foram de 45,0 g de P2O5 planta ano-1 e 23,85 g de N planta ano-1, respectivamente. As plantas de aceroleira foram conduzidas sob irrigação com água salina durante 365 dias, onde foram avaliadas quanto às características de crescimento, composição mineral foliar e produção. O aumento da salinidade da água de irrigação aumenta os teores de sódio nos tecidos a níveis prejudiciais ao crescimento, composição mineral foliar e produção da aceroleira. Adubação com 140% da recomendação de fósforo e de nitrogênio inibe a ação do estresse salino, promovendo maior produção das plantas de aceroleira irrigadas com água de até 3,0 dS m-1.

This study aimed to establish an adequate tetrazolium test procedure to estimate okra seed viability. Initially, seeds from four okra lots were immersed in alcohol (98%) for 60 minutes, followed by an 18-h soak in distilled water at 25 °C. Then, the seeds were longitudinally sectioned, immersed in 0.025, 0.050 and 0.075% tetrazolium solutions for 60, 90 and 120 minutes and maintained in an oven at 35 and 40 °C. Subsequently, the seeds were evaluated for viability, based on tissue color (bright red, pink or dark Carmine red). Simultaneously, a germination test was conducted, and its results were used as a reference for the tetrazolium test. The experiment was carried out in a completely randomized design, in a 3 x 3 + 1 factorial scheme (three concentrations of tetrazolium salt x three immersion periods, plus the control) in four replicates of 50 seeds for each treatment. The tetrazolium test to estimate okra seed viability should be conducted in 0.075% tetrazolium solution, for 90 minutes, at 35 °C.

Objetivou-se avaliar o efeito de substratos e ambientes para a produção de mudas de cajueiro anão precoce. O delineamento experimental foi inteiramente casualizado em um esquema fatorial 6 x 2, referente aos respectivos substratos (S1=25% areia + 50% solo + 25% húmus + 0g MB-4; S2=25% areia + 50% solo + 25% húmus + 50g MB-4; S3=25% areia + 50% solo + 25% húmus + 100g MB-4; S4=25% areia + 25% solo + 50% húmus + 0g MB-4; S5=25% areia + 25% solo + 50% húmus + 50g MB-4 e S6=25% areia + 25% solo + 50% húmus + 100g MB-4) e dois ambientes (Viveiro e Pleno sol), com 5 repetições. Os substratos S1 = 25% areia + 50% solo + 25% húmus + 0g MB-4 e S2 = 25% areia + 50% solo + 25% húmus + 50g MB-4, proporcionaram os melhores resultados de crescimento, acúmulo de matéria seca e qualidade, ás mudas de cajueiro. O ambiente viveiro com tela de sombrite de 50% foi o melhor ambiente para a produção de mudas do Cajueiro anão Precoce. O ambiente pleno solo em condições de clima semiárido é inadequado para a produção de mudas do Cajueiro anão Precoce.

The objective of this work was to study the effects of irrigation with saline water associated with phosphate fertilization on the emergence and early growth of cowpea plants. The assay was conducted in the greenhouse of the Department of Environmental Sciences and Technology of the Federal Rural University of the Semi-Arid (UFERSA) in Mossoró-RN, during October and November of 2015. The study adopted a randomized block with treatments arranged in a 5 x 3 grid, corresponding to five levels of water salinity (0.5, 1.5, 2.5, 3.5 and 4.5 dS m-1) and three doses of superphosphate, based upon the soil analysis (60%, 100% and 140% of the recommended dose for the crop 60 kg P2O5 ha-1), with five repetitions. The cowpea plants, cv. Paulistinha, were grown in lysimeters with capacity of 8 dm3. During the first 15 days of the initial stage of development the plants were evaluated for emergence, growth and biomass accumulation. The increase in water salinity above 1.5 dSm-1 reduced the emergence, growth and dry matter accumulation of cowpea plants. The increase of 40% in the recommendation of phosphorus fertilization of cowpea increased the growth and biomass accumulation of shoot plants, regardless of salinity.

Salvia hispanica seedlings have stood out for their potentialities in nutrients for agri-food industries. Nevertheless, studies related to this species are still scarce, especially with respect to agronomic factors that enable its propagation and development. Hence, this study aimed to evaluate germination, vigor and osmotic adjustment of S. hispanica seeds and seedlings subjected to water and thermal stress. The experimental design was completely randomized, with treatments arranged in factorial scheme, corresponding to five levels of polyethylene glycol (PEG 6000) (0.0; -0.1; -0.2; -0.3 and -0.4 MPa) and five temperatures (20, 25, 30 and 20-30 °C), with four replicates of 50 seeds in each treatment. Germination test was set on blotter paper, moistened with PEG 6000 solutions at the previously mentioned potentials, under 8-h photoperiod. The following variables were analyzed: germination, germination speed index, seedling shoot length, seedling root length, seedling dry matter and contents of chlorophyll, carotenoids, amino acids, proline and sugars. Polyethylene glycol levels of -0.4 MPa at all temperatures and -0.3 MPa at 30 °C and 20-30 °C enable germination and vigor of S. hispanica seedlings. S. hispanica seedlings are able to perform osmotic adjustment under water stress conditions up to the level of -0.3 MPa, when grown from seeds germinated at temperatures of up to 25 ºC.

The quantitative and qualitative scarcity of water resources is a frequent problem in the semi-arid region of the Brazilian Northeast. The availability of water for irrigation with high salts contents is common, affecting the growth and development of the crops. Thus, it is necessary to adopt strategies that allow the establishment of irrigated cultivation in this region. The objective of this work was to evaluate the effect of water salinity and phosphorus/nitrogen combinations on the ecophysiology of the West Indian cherry grafted in the first year of cultivation. The research was carried out in a protected environment, in lysimeters filled with a Regolithic Neosol of loamy clay texture, having low initial phosphorus content. The experiment was arranged in a randomized block design, arranged in a 5x4 factorial scheme, with five levels of electrical conductivity of the irrigation water - CEa (0.6, 1.4, 2.2, 3.0 and 3.8 dS m -1) and four manures of fertilization with phosphorus and nitrogen (100: 100, 140: 100, 100: 140 and 140: 140% of the recommendation of P/N), with three replications, each plot consisting of one plant. Increased salinity of irrigation water reduced growth, photosynthesis and the production of West Indian cherry. Fertilization with 140% of the phosphorus and nitrogen recommendation minimizes the deleterious effect of salinity on West Indian cherry irrigated with water up to 3.0 dS m-1.

The melon crop is normally developed in semiarid regions, where water resources are limited. This scarcity of water is a strong stressor on the crops, and requires the supplementation of existing water supplies with poor quality water, especially saline water. This can impede the growth and production of plants; however, the use of tolerant genotypes may minimize this problem. Thus, a greenhouse experiment was developed at the Federal University of Campina Grande - UFCG, Pombal Campus, Paraiba State, Brazil, in order to study the emergence, initial growth, and tolerance of melon cultivars irrigated with waters of different salt content. We studied three melon cultivars (Gaúcho Redondo, Gaúcho Casca de Carvalho and Halles Best Jumbo) irrigated with five levels of saline water (0.6; 1.2; 1.8; 2.4; and 3.0 dS m-1), arranged in a 3 x 5 factorial scheme, with the treatments distributed in a randomized block design with four replications. The plants seeds were monitored for 30 days after sowing, and at 30 days the growth and salinity tolerance index was evaluated. Cultivar Halles Best Jumbo was the most tolerant to saline water during initial stage of growth, while the Gaucho Redondo was more sensitive to salinity. It was found that saline waters up to 1.8 dS m-1 were suitable for irrigation of melon plants round Gaucho and waters up to 2.4 dS m-1 could be used for irrigation of Gaucho Casca de Carvalho and Halles Best Jumbo crops during the initial growth phase.

Seed companies increasingly need to obtain reliable results on seed vigor. Therefore, the objective was to verify the efficiency of the respiratory activity measurement, by the CO2 released, to classify the vigor of okra seed lots. For this, five seed lots of okra cv. "Santa Cruz 47" were used. In order to determine seed physiological quality, the following tests were performed: germination, seedling emergence, emergence speed index, shoot length, total dry matter, potassium leaching, electrical conductivity and respiratory activity. Mean values of germination and vigor were compared by Tukey's test. Respiratory activity was correlated with germination and other vigor tests by the Pearson's correlation. The results indicate that CO2 measurement is a promising method to identify vigor differences between okra seed lots.

Most plant species are susceptible to the effects of salinity, such as increases in osmotic potentials and deleterious ionic effects, which in turn affect water absorption in plants and, consequently, compromise germination and seedling growth. Hence, this study aimed to evaluate the effects of salinity on the germination, initial growth, and physiological and biochemical components of S. hispanica seedlings at different temperatures. The experimental design was completely randomized, with treatments distributed in a 5 x 4 factorial scheme with five saline concentrations (0.0 (control), 4.5, 9.0, 13.5, and 18.0 dS m-1) four temperature regimes (20, 25, 30, and 20-30°C), and four replicates of 50 seeds per treatment. The experiment evaluated the germination, growth, biochemical components (chlorophyll a, chlorophyll b, total carotenoids, amino acids, proline and sugars) and phytomass accumulation of S. hispanica seedlings. Saline levels higher than 4.5 dS m-1 together with treatment temperatures of 30 or 20-30°C negatively affected the germination, vigor, growth and biochemical components of the seedlings. The 25°C treatment temperature promoted the best conditions for the development of S. hispanica seedlings up to the saline level of 9.0 dS m-1.

The seminiferous propagation of the pomegranate tree is dramatically affected by the presence of a sarcotesta, which often makes this method of propagation unfeasible. Therefore, the aim of this study was to evaluate the production of rootstocks for Mollar pomegranate cuttings under different management techniques in the dry and wet seasons. Two experiments were performed, one in the dry season (August to December 2012, Experiment I), and another in the rainy season (January to June 2013, Experiment II). The experiments used a completely randomized design with four replications and five seedlings per plot. To monitor plant growth and physiology, a factorial scheme using two factors, management of softwood cuttings (cuttings with leaves; cuttings without leaves; and cuttings without leaves, but with an incision at the base) and evaluation times (60, 70, 80, 90, and 100 days after planting [DAP] in Experiment I and 60, 70, 80, 90, 100, 110, 120, 130, 140, and 150 DAP in Experiment II) was adopted. The propagation material was collected from commercial plants, from the median portion of the branch. The cuttings were approximately 15 cm long. Cuttings without leaves with an incision at the base were more suitable for vegetative propagation of Mollar pomegranate trees, regardless of season (dry or wet). Seedlings grown in the rainy season had higher survival rates and higher root and shoot growth. The use of cuttings with leaves for the vegetative propagation of the Mollar pomegranate tree in the dry season is not feasible. The best time to transplant Mollar pomegranate tree seedlings, in the rainy season, is at 130 DAP, at an average height of 45 cm.

This work aimed to study the effect of chemical and organic conditioners on the chemical attributes of a saline-sodic soil and on the initial growth of two castor bean cultivars. Two experiments were performed in the green house of the Center of Human and Agrarian Sciences of the Paraíba State University (CCHA-UEPB), Campus IV, Catolé do Rocha-PB. In the first experiment, an entirely randomized experimental design with five treatments [(saline – sodic soil without conditioners (SSC), saline – sodic soil + biofertilizer at 10% of the soil volume (SS + B), saline – sodic soil + chalk at 100% of the chalk requirement (SS + C), saline – sodic soil + chalk + biofertilizer (SS + C + B), and non-saline soil (NSL)] and eight replicates was adopted. In the second randomized experiment the treatments were displayed in a 5 × 2 factorial scheme, referring to the five corrective treatments used in the first experiment and the two castor bean plant cultivars (BRS Nordestina and BRS Paraguaçu), with four replicates. The application of chalk combined with biofertilizer promoted a better initial development of the castor bean plant in comparison with other recovering treatments. This indicates the corrective effect of chalk on sodicity and of both treatments on the nutrient availability for the plants. The bovine biofertilizer alone did not reduce the sodicity of the sodic – saline soil. Under the evaluated conditions, the BRS Nordestina surpassed the BRS Paraguaçu.

The commercial cultivation of pomegranate plants has been growing throughout Brazil and has attracted the interest of northeastern fruit producers. However, for the establishment of pomegranate in the in natura fruit market, it is necessary to find out the refrigeration temperature most suitable for commercializing the product in distant markets. This study aimed to characterize the quality of ‘Molar’ pomegranate, during the storage of in natura fruits under different refrigeration temperatures (6 ºC, 10 ºC and 12 ºC). A completely split-plot randomized design, with four replications and four fruits per plot, was used. It was concluded that ‘Molar’ pomegranates stored at 12 ºC, for 36 days, followed by two days at 24 ºC and 43 ± 5 % RH, remain satisfactory for in natura commercialization, without affecting their biometric quality attributes and with small losses in their physicochemical properties. The temperatures of 6 ºC and 10 ºC may also be used for the refrigerated storage of the ‘Molar’ pomegranate, but with a smaller volume of juice per fruit.

In order study the different management techniques stakes pomegranate 'Wonderful' for vegeta-tive propagation in the dry and rainy season, in the semiarid region of Paraiba. The survey was conducted in the greenhouse, in the Campus Center of Science and Agrifood Technology, Federal University of Campina Grande, in the City of Pombal-PB, Brazil. There were two experiments, one in the dry season, which com-prised from August to December 2012 (Experiment I), and another in the rainy season, from January to June 2013 (Experiment II). Experiments were conducted in a completely randomized design (CRD) with four repli-cations and five plants per replication. To monitor the growth and physiology of the plant was adopted factorial consisting of two factors, managements of cuttings (cuttings with leaves, cuttings without leaves and cuttings without leaves more base incision) in function evaluation times (Days after planting). The propagation material was purchased from commercial plants and cuttings of softwood type. The samples were standardized by size, standard length 15 cm. The management of the cuttings leafless more incision in the base is most suitable for the propagation of pomegranate 'Wonderful'. The management of the cuttings with leaves is not suitable for the propagation of the pomegranate 'Wonderful', in the dry season. The rainy season is the ideal time for the pro-duction of seedlings of the pomegranate 'Wonderful'. The ideal time to obtain saplings of pomegranate 'Wonderful' is 144 days after planting the cuttings.

Objetivou-se estudar a emergência e o crescimento inicial de plantas de milho adubadas com esterco bovino sob dois regimes hídricos. O experimento foi conduzido em condições de túnel plástico da Universidade Federal de Campina Grande, Campus de Pombal, Paraíba, no período de Dezembro de 2014 a janeiro de 2015. O arranjo dos tratamentos constituiu um esquema fatorial 4 x 2, correspondentes a quatro doses de esterco bovino (0,0; 4,0; 8,0 e 12 t ha-1) e dois níveis de água disponível de 50 e 100 % da Capacidade de campo, mantido após as irrigações do solo, com 8 tratamentos e quatro repetições, totalizando 32 unidades experimentais. O ensaio foi realizado em unidades experimentais compostas por vasos de 18 dm3 de capacidade, semeando manualmente dez sementes por vaso. As plantas foram conduzidas por 20 dias após a semeadura, onde foram avaliadas quanto à emergência, o crescimento inicial e o acúmulo de massa seca. A redução da água disponível para 50 % da capacidade de campo não influência a emergência e o crescimento inicial do milho. A dose de 12 t ha-1 de esterco bovino favorece ao maior crescimento inicial e acúmulo de massa seca das plantas de milho cultivar AG 1051.

Objetivou-se estudar a emergência e o crescimento inicial de plantas de milho adubadas com esterco caprino sob dois regimes de disponibilidade de água no solo. O arranjo dos tratamentos constituiu um fatorial 4 x 2, correspondentes a quatro doses de esterco caprino (0, 4, 8 e 12 t ha-1) e dois níveis de água disponível de 50 e 100% da capacidade de campo, mantido após as irrigações do solo, com 8 tratamentos e quatro repetições, totalizando as 32 unidades experimentais. O ensaio foi realizado em unidades experimentais compostas por vasos de 18 dm3 de capacidade, semeando manualmente quatro sementes por vaso. As plantas foram conduzidas por 20 dias após a semeadura, sendo avaliadas quanto à emergência, o crescimento inicial e o acúmulo de massa seca. A redução de 50% de água no solo não exerce impactos negativo sobre a emergência e crescimento inicial das plantas de milho AG1051. A dose de esterco caprino de 12 t ha-1 promoveu o maior crescimento e acúmulo de massa seca das plantas de milho. Initial growth of maize under manure goat doses and water availability in soil Abstract: The objective was to study the emergence and initial growth of corn plants fertilized with goat manure under two water availability regimes in soil. The treatment arrangement consisted of a 4 x 2 factorial, corresponding to four doses of goat manure (0, 4, 8 and 12 t ha-1) and two levels of available water of 50 and 100% of field capacity, maintained after The soil irrigations, with 8 treatments and four replications, totalizing the 32 experimental units. The experiment was carried out in experimental units composed of pots of 18 dm3 of capacity, manually seeding four seeds per pot. The plants were conducted for 20 days after sowing, where they were evaluated for emergence, initial growth and dry mass accumulation. The reduction of 50% of water in the soil does not have a negative impact on the emergence and initial growth of AG1051 maize plants. The dose of goat manure of 12 t ha-1 promoted the highest growth and accumulation of dry mass of maize plants.

Objetivou-se estudar o desenvolvimento inicial de plantas de milho sob níveis de irrigação e doses de esterco de galinha. O experimento foi conduzido em condições de túnel plástico da Universidade Federal de Campina Grande, Campus de Pombal, Paraíba, no período de Dezembro de 2014 a janeiro de 2015. O arranjo dos tratamentos constituiu um fatorial 5 x 2, correspondentes a cinco doses de cama de frango e dois níveis de água disponível (AD) de 50 e 100% da CC, mantido após as irrigações do solo, com 10 tratamentos e quatro repetições, totalizando as 40 unidades experimentais. O ensaio foi realizado em unidades experimentais compostas por vasos de 18 dm3 de capacidade, semeando manualmente quatro sementes por vaso. As plantas foram conduzidas por 20 dias após a semeadura, onde foram avaliadas quanto a emergência, o crescimento inicial e o acúmulo de massa seca. As doses de 8,4 e 8,5 t ha-1 promovem o maior crescimento das plantas de milho na fase inicial de crescimento. Não houve influência da água disponível e da interação água disponível e as doses de cama de frango sobre a emergência e crescimento da plantas de milho cultivar AG 051 durante os primeiros 20 após a semeadura. Não houve influência da água disponível e da interação água disponível e as doses de cama de frango sobre a emergência e crescimento da plantas de milho cultivar AG 051 durante os primeiros 20 após a semeadura. Doses of chicken manure and water available under the initial development of maize Abstract: The objective was to study the initial development of corn plants under irrigation levels and doses of chicken manure. The experiment was carried out in plastic tunnel conditions of the Federal University of Campina Grande, Campus of Pombal, Paraíba, from December 2014 to January 2015. The treatment arrangement consisted of a 5 x 2 factorial, corresponding to five doses of chicken litter and two levels of available water (AD) of 50 and 100% CC, maintained after soil irrigation with 10 treatments and four replications, Totaling the 40 experimental units. The experiment was carried out in experimental units composed of vessels of 18 dm3 capacity, manually seeding four seeds per pot. The plants were conducted for 20 days after sowing, where they were evaluated for emergence, initial growth and accumulation of dry mass. The doses of 8.4 and 8.5 t ha-1 promote the highest growth of maize plants in the initial phase of growth. There was no influence of available water and the interaction of available water and broiler litter doses on the emergence and growth of AG 051 maize plants during the first 20 years after sowing. There was no influence of available water and the interaction of available water and broiler litter doses on the emergence and growth of AG 051 maize plants during the first 20 years after sowing.

This study evaluated the effects of different light regimes and temperatures on the germination of S. hispanica seeds and used a factorial scheme in a completely randomized experimental design, in which three light conditions were combined with six temperatures (constant 20, 25, 30 and 35°C and alternating 20-30 and 25-30°C), totaling 18 treatments with four 50-seed replications. The seeds were sown on blotting paper in transparent plastic boxes and then allowed to germinate in Biochemical Oxygen Demand germinators. The seeds were evaluated over a period of eight days with respect to the following variables: germination percentage, average germination time, shoot and root lengths, shoot and root dry weights and root-shoot ratio. The data were submitted to Tukey’s test (p ≤ 0.05%). The S. hispanica seed (beige colored) germination test can be carried out at constant (25°C) or alternating (25-30°C) temperatures. The germination of the seeds was indifferent to the light conditions evaluated; however, there was increased seedling growth and dry matter accumulation in the presence of light. The duration of the S. hispanica seed germination test can be five days, with the first count on the second day after sowing.

The papaya crop has great socio-economic expression in the Brazil and is mainly grown in the northeastern region, which is facing serious problems of water shortage, particularly in its qualitative aspect, due to high concentration of salts in water. For best performance of a crop it is necessary to adopt managements strategies, such as the use of tolerant cultivars, thus, aimed to assess the balance of salts in the substrate, growth and partition of biomass of varieties of papaya irrigated with saline water. The experiment was conducted in a randomized complete block design with treatments arranged in a 2 x 4 factorial arrangement , consisting of two cultivars of papaya (Sunrise Solo and Tainung - 01) and four levels of water salinity (1.2, 2.4, 3.6 and 4.8 dS m -1) with three replications. The balance of salts in the substrate, growth rate and the dry matter partitioning were evaluated to determine crops' tolerance to salinity in the initial growth phase. The water salinity increased linearly electrical conductivity, sodium absorption ratio and exchangeable sodium percentage of the substrate, and reduced growth and the biomass of varieties of papaya, in which reductions in biomass accumulation followed the order leaves > roots > stem. Salinity reduced the percentage of dry weight of stem and leaves and increased the dry weight of roots.

The seed quality evaluation is essential in quality control programs. Thus, vigor tests have been developed to differentiate seed lots, due to the limitations of the germination test. This study aimed at evaluating the electrical conductivity test efficiency for determining the physiological quality of sunflower seeds. Ten lots of sunflower seeds (Catissol and Multissol cultivars) were used. Initially, the quality of each lot was determined, besides the seeds moisture content, by using tests of germination, first counting and seedling emergence, in a greenhouse. Then, the seeds were submitted to the electrical conductivity test, for four soaking periods (6, 12, 18 and 24 hours), by using disposable plastic cups containing 25 and 50 seeds, in 50 mL and 75 mL of deionized water, at 25ºC and 30ºC. The experimental design was completely randomized, in a 5x4 factorial scheme (five lots and four soaking periods), separately for each cultivar, with four replications. It was possible to conclude that the electrical conductivity test combining 25ºC, 75 mL of deionized water and 50 seeds was sufficiently sensitive to evaluate the physiological quality of sunflower seeds.

Basil is a medicinal aromatic plant of the Lamiaceae family, it is rich in essential oils with high industrial interest. The present work to verify the production of basil plants, from different sources and combinations of substrates. The study was conducted in greenhouse Sector, Department of Soil Environmental Science, Federal Rural University of the Semi-Arid (UFERSA) in May 2010. Basil seedlings were grown from seeds from plants on the campus of UFERSA. The experimental design was randomized blocks representing five treatments and four replicates of 10 seedlings per plot. The treatments employed arisco, sand, cattle manure and earthworm castings in different combinations. Features diameter, leaf number, shoot length and root dry mass of shoots and roots were evaluated thirty days after sowing. It was found that adding cattle manure in the compositions of the substrates was increased growth and development of seedlings. In the production of seedlings of basil is recommended mixture of substrates containing cattle manure, sand and arisco in the ratio 1:1:1.

Hyptis suaveolens (L.) Poit.) (Lamiaceae) is a medicinal plant widely used in folk medicine in Northeast Brazil as a treatment for respiratory diseases, antispasmodic, sweat and useful in the treatment of gout. The aim of this study was to evaluate hereto the influence of different lengths of cuttings in rooting ofbamburral. The test was conducted for 30 days in the greenhouse of the Department of Environmental Sciences, Federal University of Semi-Arid (UFERSA). The experimental design was randomized blocks with four cutting lengths (5; 10; 15 and 20 cm) and four replications and 10 cuttings per plot. After 30 days of planting, characteristics were evaluated: percentage of survival, rooting percentage, longest root length, diameter and initial end of cutting, the dry mass of shoot and root. Conclude that the length of piles does not affect the rooting of bamburral.

The controlled deterioration test has frequently been used to evaluate the vigor of several species and could be an alternative for evaluation of the vigor in jilo seeds. The objective of the present work was to study the controlled deterioration to evaluate the physiological quality of jilo seeds. Five seed lots, cv. Verde Claro Comprido, were submitted to tests of germination, germination first count, seedling emergence and deterioration (19%, 21% and 24% water content, at 45ºC and 24 and 48 hour periods). The 24% water/24h at 45ºC combination, for the controlled deterioration test, was efficient to detect vigor differences among jilo seed lots.

Objetivou-se avaliar a viabilidade do uso de indutores de enraizamento para a propagação vegetativa por estaquia do mofumbo. O experimento foi conduzido no período de setembro de 2011 a Junho de 2012 em casa de vegetação do Horto de Plantas Medicinais, do Departamento de Ciências Vegetais da Universidade Federal Rural do Semi-Árido – UFERSA, situada no município de Mossoró-RN. O delineamento experimental adotado foi o inteiramente casualizado, com quatro repetições, cada parcela experimental foi constituída por dez estacas. Os tratamentos foram compostos por: T1- Testemunha, T2- Embebição em AIB na concentração de 3000mg/L por 5 min, T3- Embebição emextrato de tiririca (10%), T4- Embebição em água de coco pura, T5- Embebição polpa de banana pura, T6- Embebição em solução de água de coco + polpa de banana (200 mL/L e 100 g/L), respectivamente. Nas condições em que foi realizado o experimento, o mofumbo não se adequou ao processo de propagação via estaquia, sendo necessários mais estudos com propagação vegetativa dessa espécie. A imersão emextrato de tiririca (10%) e em polpa de banana pura promoveram os melhores resultados de enraizamento.

Essa pesquisa teve como objetivos avaliar a biometria dos frutos e sementes de Calotropis procera, bem como estabelecer as condições de luz, temperatura e substrato adequados à germinação de sementes dessa espécie. A biometria dos frutos foi determinada numa amostra de 100 unidades, coletados ao acaso, no município de Mossoró-RN, constituindo-se nas determinações de comprimento, largura, espessura e peso de frutos e sementes. Dessas sementes, numa amostra de 100 unidades retiradas aleatoriamente, determinaram-se comprimento, número de sementes por fruto, teor de água e peso de mil sementes. Foram avaliadas as seguintes variáveis: germinação e tempo médio de germinação. Para análise empregou-se o delineamento experimental inteiramente casualizado em arranjo fatorial 6x3x2 sendo seis temperaturas (20, 25, 30, 35, 20-30 e 25-30 ºC), três substratos (areia, papel toalha e mata-borrão) e duas condições de luminosidades (presença e ausência de luz), com seis repetições de 50 sementes. Os dados biométricos foram analisados através da estatística descritiva e para os caracteres germinação e tempo médio de germinação utilizou-se análise de variância e teste de Tukey através do SISVAR 4.5. Concluiu-se que há variabilidade para os caracteres relacionados às dimensões e pesos de frutos de flor-de-seda; o número de sementes por fruto é elevado, favorecendo a disseminação da espécie. Recomenda-se que as contagens inicial e final do teste de germinação sejam realizadas aos 5 e 10 dias após a semeadura, respectivamente. A temperatura constante de 30 ºC, alternada de 25-30 ºC e os substratos areia e papel toalha são condições adequadas para a germinação e as sementes são indiferentes à luminosidade.

RESUMOOs testes de germinação e de vigor são componentes essenciais do processo de controle de qualidade das empresas produtoras de sementes. Diante disso, nesta pesquisa o objetivo foi estudar a metodologia do teste de condutividade elétrica, verificando sua eficiência na identificação de diferentes níveis de vigor de lotes de sementes de coentro. Para tanto, utilizaram-se quatro cultivares (Português, Super Verdão, Tabocas e Verdão), cada uma representada por quatro lotes de sementes, que inicialmente foram submetidas às avaliações do grau de umidade, germinação, primeira contagem de germinação e emergência de plântulas. O teste de condutividade elétrica foi realizado com 25 e 50 sementes embebidas em 50 e 75 mL de água destilada, a 25 ºC, por 2, 8 e 24 horas. O teste de condutividade elétrica é eficiente para a avaliação do potencial fisiológico de sementes de coentro quando conduzido com 50 sementes imersas em 50 mL de água destilada, a 25 ºC, após duas horas de embebição.

ABSTRACT Cowpea is widely grown in the Brazilian semiarid region, however, due to excess salts in the soil and irrigation water constantly low crop productivity has been observed. Accumulation of salts in the soil, growth and biomass partition of cowpea under salt stress and phosphorus fertilization was evaluated in this study. The assay was conducted in a greenhouse in Mossoró, State of Rio Grande do Norte, Brazil, from September to December 2015, using a Alfissol Latosolic with low phosphorus content. The experiment was carried out in a randomized block design in a factorial 5 x 3 arrangement, consisting of five water salinity levels (0.5, 1.5, 2.5, 3.5 and 4.5 dS m-1) and three doses of superphosphate (60, 100 and 140% of the recommended dose for crop - 60 kg ha-1 of P2O5), with five repetitions. The plants of cowpea cv. Paulistinha were cultivated for 49 days after sowing in lysimeters with 8 dm3 capacity. During this period was determined the accumulation of salts in the soil, growth and biomass partition plants. Water with salinity higher than 1.5 dS m-1 increased soil salinity above the crop's threshold of 4.9 dS m-1, 21 days after sowing. Increased salinity impaired growth and biomass partition of cowpea plants, with greater accumulation of dry matter in the leaves and stem in comparison to the root. Hinghest dose of superphosphate promoted greater growth of cowpea plants.

ABSTRACT The tetrazolium test is a quick and effective method for evaluating viability in seeds. The aim of this study was to determine a methodology for using the tetrazolium test, and its efficiency in verifying viability in seeds of the gherkin (Cucumis anguria L.). Consequently, five batches of gherkin seed were initially evaluated by the tests for germination, first count and speed of germination. The batches were then subjected to treatments in order to adjust the methodology for the tetrazolium test, evaluating three concentrations of tetrazolium solution (0.100, 0.075 and 0.050%), kept in the dark for two, four and six hours, under temperatures of 35 °C and 40 °C, with four replications of 25 seeds per treatment. At the end of the staining period, the seeds were washed in running water, split lengthways between the cotyledons, and classified as viable and non-viable. Evaluation of viability in seeds of the gherkin by tetrazolium test is efficient when carried out at a concentration of 0.050%, either for six hours at 35 °C or four hours at 40 °C.

ABSTRACT Piptadenia stipulacea (Benth.) Ducke presents slow and uneven germination due to integumentary dormancy. In addition, there are no standardized indications as to the temperature and substrate for conducting the germination test in the laboratory. Thus, the objective was to evaluate methods of dormancy overcoming, temperatures and substrates in the germination and vigor of P. stipulacea seeds. For this, two experiments were installed, the first one in a completely randomized design, with 4 replicates of 25 seeds and treatments to overcome dormancy were: immersion in water at 100 °C for 1; 2; 3; 4; 5 and 6 min; immersion in concentrated sulfuric acid (H2SO4 - 98% P.A) for 1; 4; 7; 10 and 13 min; scarification on sandpaper no 80; in the region opposite the micropyle and intact seeds. At 21 days after sowing, emergency, emergency speed index and mean emergency time were evaluated. In experiment II, the experimental design was completely randomized in a 4 x 6 factorial scheme, with four replicates of 25 seeds, using the substrates between sand, paper, paper roll and vermiculite at temperatures of 20; 25; 30; 35; 40 °C and alternated 20-30 °C, the variables analyzed were first count, germination, mean germination time and germination speed index. In order to overcome seed dormancy of P. stipulacea, it is recommended that the pre-germinating treatment be set in the region opposite to the micropyle, and to evaluate the germination and vigor of these seeds, the temperature of 30 °C and 20-30 °C can be used with the roller substrate of paper.