ABSTRACT The aim of the present study was to evaluate the effect of biostimulant containing amino acids and yeast extract on the physiological and reproductive characteristics of mango cv. Tommy Atkins during the shoot maturation phase in tropical semi-arid region. The experimental design consisted of randomized blocks with five treatments, five replications and five plants per plot. Treatments consisted of: T1) two foliar sprays with [biostimulant + KCl] + two foliar sprays with K2SO4; T2) No biostimulant and four foliar sprays with K2SO4; T3) three individual foliar sprays with biostimulant and one foliar spray with K2SO4; T4) two foliar sprays with biostimulant and two foliar sprays with K2SO4; and T5) two foliar sprays with [biostimulant + K2SO4] + one foliar spray with K2SO4. There is a positive effect of the biostimulant containing amino acids and yeast extract on transpiration, internal CO2 concentration, water-use efficiency and number of reproductive and non-differentiated shoots of mango cv. Tommy Atkins cultivated under tropical semi-arid condition, with attenuating effect on plant abiotic stress. For shoot maturation of mango cv. Tommy Atkins, three foliar sprays with biostimulant containing amino acids and yeast extract (10 mL per plant) and one with K2SO4 (3%), starting at 45 days after paclobutrazol application (T3), can be recommended.

Resumo -A produção de mudas com qualidade é fundamental na exploração das culturas agrícolas, e os bioestimulantes apresentam-se como ferramentas benéficas nessa fase da planta. O estudo objetivou avaliar as diferentes concentrações de bioestimulante composto por extrato de algas, no favorecimento da expansão radicular e desenvolvimento vegetativo inicial de mudas de uva, cultivar Crimson Seedless enxertadas em porta-enxerto SO4. O experimento foi realizado em viveiro comercial na cidade de Petrolina-PE. O delineamento experimental utilizado foi o inteiramente casualizado, com cinco tratamentos e quatro repetições. Os tratamentos foram: (T1) 0; (T2) 0,75; (T3) 1,12; (T4) 1,5 e (T5) 1,87 mL planta -1 do bioestimulante. Aos 45 dias após a enxertia foram analisados o comprimento e diâmetro da brotação do enxerto; área foliar; diâmetro, densidade, área, comprimento e matéria seca das raízes e matéria seca da parte aérea. Os dados foram submetidos à análise de variância e análise de regressão polinomial. Os melhores resultados foram proporcionados pela aplicação da dose 0,75 mL planta -1 . O aumento da dose causou redução na expressão das variáveis. Conclui-se que o bioestimulante é uma ferramenta importante na produção de mudas com qualidade. Palavras-Chave -Vitis vinifera, Ascophyllum nodosum, propagação vegetativa, reguladores vegetais.Abstract -The seedling production with quality is essential for growing agricultural crops, and the biostimulants are beneficial tools for this plant phase. The study aimed to evaluate the different concentrations of biostimulant containing algae extract on root expansion and initial vegetative development of grape seedlings cv. Crimson Seedless grafted on SO4 rootstock. The experiment was conducted in commercial nursery in Petrolina county, Pernambuco state, Brazil. The experimental design used was the completely randomized design, with five treatments and four replicates. The treatments were: (T1) 0; (T2) 0.75; (T3) 1.12; (T4) 1.5 and (T5) 1.87 mL plant -1 of the biostimulant. At 45 days after grafting the length and diameter of the graft sprouting; leaf area; diameter, density, area, length, and dry weight of roots and shoots were analyzed. The data were subjected to analysis of variance and polynomial regression. The best results were provided by 0.75 mL plant -1 biostimulant dose. Increasing biostimulant doses caused the reduction of variables expression. It is concluded that the biostimulant is an important tool for production of quality grape seedlings.

Micronutrientes foliares na goiabeira fertirrigada com biofertilizante e nitrogênio no semiárido Resumo Demandados em pequenas quantidades, os micronutrientes exercem papel fundamental para o desenvolvimento adequado das plantas e podem ser fornecidos por insumos sintéticos ou orgânicos, como os biofertilizantes. Dessa forma, um experimento foi conduzido entre julho de 2014 e agosto de 2015, na área experimental da Universidade Federal do Vale do São Francisco, Petrolina-PE, para avaliar os teores foliares de micronutrientes em goiabeira Paluma em função de fertirrigação com biofertilizante bovino e adubação nitrogenada. O delineamento experimental foi em blocos casualizados em esquema fatorial (5 x 2) referentes às concentrações de biofertilizante bovino (0, 2,5, 5,0, 7,5 e 10%) e adubação mineral com nitrogênio (50% e 100% do recomendado segundo a demanda da cultura), com quatro repetições e cinco plantas por parcela. Apenas os teores foliares de Mn são afetados pelo biofertilizante bovino em goiabeiras fertirrigadas com 100% de N. Os teores foliares de todos os micronutrientes (Mn, B, Fe e Zn) não são influenciados pela fertirrigação nitrogenada. O biofertilizante é eficiente no fornecimento de Fe. Palavras-chave: Psidium guajava L., matéria orgânica, nutrição de plantas Leaf micronutrients in guava fertigated with biofertilizer and nitrogen in semiarid Abstract Required in small amounts, micronutrients play a key role for adequate plant development, which can be supplied by synthetic or organic fertilizers, such as biofertilizers. Thus, an experiment was conducted between July 2014 and August 2015, in the experimental area of the Federal University of the São Francisco Valley, Petrolina-PE, Brazil, to evaluate the micronutrient leaf concentrations of Paluma guava as a function of fertigation with bovine biofertilizer and Nitrogen fertilization. The experimental design was a randomized complete block design (5 x 2) referring to the concentrations of bovine biofertilizer (0, 2.5, 5.0, 7.5 and 10%) and N-fertilizing (50% and 100% of N dose following plant demand), with four replicates and five plants per plot. Only the leaf Mn concentrations are affected by bovine biofertilizer in guava trees fertigated with 100% of recommended N. Leaf concentrations of all the micronutrients (Mn, B, Fe and Zn) are not influenced by nitrogen fertigation. The biofertilizer is efficient in providing Fe.

Aims: To evaluate the 'Canary' and 'Hale's Best Jumbo' melon yield and fruit characteristics as a function of fertilization management and soil cover with mulch. Study Design: The design was a randomized complete block design in a 2x3x2 factorial scheme, with three replications and seven plants per plot. Place and Duration of Study: The experiment was conducted from June to September 2015, at the Center of Agrarian and Biodiversity Sciences of the Federal University of Cariri, located in the city of Crato, Cariri region, Brazil. Methodology: Two varieties of melon ('Canary' and 'Hale's Best Jumbo') were studied under three fertilization managements (mineral fertilization via soil, mineral fertilization via soil + organic fertilization and mineral fertilization via soil + foliar fertilization) with the presence or absence of soil cover with polyethylene mulch. Results: The use of mineral + organic fertilization and mineral + leaf fertilization promoted an increase in fruit mass and yield of approximately 3.93 t ha-1 (25.50%) and 4.64 t ha-1 (30%), respectively. Both melon cultivars presented the best responses grown on plastic mulch, with yield increases of 79.66% and 26.16% for 'Canary' and 'Hale's Best Jumbo', respectively. Moreover, the 'Hale's Best Jumbo' cultivar presented higher soluble solids contents than the 'Canary' melon, with an increase of 11.26% (0.76 ° Brix). Conclusion: The use of soil cover and additional fertilization (organic or foliar) in the cultivation of melon provides an increase in size, mass and productivity, while soil cover increases the soluble solids content in fruits.

Aims: The aim of this work was to evaluate the yield and the physical quality of the yellow passion fruit accession ‘Guinezinho’ as a function of the within-row plant spacing, with saline irrigation water in consecutive growing seasons. Study Design: The experiment was arranged in randomized blocks, with four replicates and 12 plants per parcel, in a 4 x 2 factorial arrangement, referring to the spacing in the planting lines of 3, 6, 9 and 12 m, and two consecutive growing seasons. Place and Duration of Study: The experiment was developed in the municipality of Coronel Ezequiel, Rio Grande do Norte state, Brazil, within the months of April 2013 and October 2014. Methodology: The seedings were transplanted in the spacings of 3, 6, 9 and 12 m, and distant 2 m within lines according to the treatments; they were conducted in a vertical shoot position (VSP) training system, and daily irrigated during the arid period with saline water (ECiw = 3.4 dS m-1). The following characteristics were evaluated: fruit yield, fruit mass, longitudinal and transversal fruit diameter, pulp yield, peel mass and peel thickness. Results: The interaction between spacing and growing season exercised a significant effect on the fruit yield, longitudinal fruit diameter, pulp yield, thickness and mass of the peel (P = .05).  The variables transversal diameter and fruit mass only varied within the growing seasons (P = .05). The plants cultivated in the 3 m spacing were the most productive in the two seasons, with 23.7 and 36.3 t ha-1, in the first and second seasons, respectively. Conclusion: The highest yield of the yellow passion fruit accession ‘Guinezinho’ was obtained in the smaller plant spacing in the lines. Except for the pulp yield, the yield and physical quality of the fruits were superior in the second growing season. The irrigation with highly saline water, in this type of soil, did not compromise the productive ability of the passion fruit accession ‘Guinezinho’.

Adequate nutritional status is fundamental for the fruiting process of mango trees (Mangifera indica L.). In this context, plant biostimulants are substances that promote physiological and nutritional changes, benefiting production. The present study evaluated the effect of biostimulants on the nutritional status and fruit production of ‘Kent’ mango trees. The experiment was carried out in the Brazilian semiarid region over 2 consecutive years, 2016 and 2017. Leaf treatments with biostimulants were applied in three phases (preflowering, beginning of flowering, and full flowering) during both seasons. The treatments were as follows: T1) control (without biostimulants); T2) biostimulants containing nutrients and L-α-amino acids; T3) biostimulants containing nutrients and Lithothamnium algae extract; T4) biostimulants containing nutrients and sucrose; and T5) biostimulants containing nutrients, free amino acids, and Lithothamnium algae extract. The results show that there was no effect of the biostimulants for chlorophyll a, b, and total indices or for total leaf soluble carbohydrates. Some of the treatments affected the leaf concentrations of N, K, Mn, Fe, and Zn, whereas only T2 in 2016 and T5 in 2017 increased the number of fruits per panicle if compared with nontreated plants. In 2016, the production per tree was higher in T5 compared with the other treatments, whereas it was greater in 2017 in both T2 and T5 with increases of 37.4 and 23.1 kg per tree, respectively, compared with the control treatment. Biostimulants containing soluble nutrients, L-α-amino acids, free amino acids, and Lithothamnium algae extract benefit the nutritional status and increase the fruit production of mango ‘Kent’.

The genus Heliconia is commercially detached by the exotic appearance of the inflorescences but is susceptible to lack of moisture in the soil, being necessary the irrigation management. In this sense, the objective was to evaluate the effect of different irrigation levels on the plant growth and productive characters of Heliconia psittacorum cv. Golden Torch cultivated in vase. The experiment was conducted from March to October 2014, in a randomized blocks design. Five treatments corresponding to the different irrigation levels were used [50, 75, 100, 125 and 150% of the evaporation measured in Class A (ECA)] with four replicates and two plants per replicate. The following evaluations were carried out: number of days for the emergence of the first tiller, number of days for the emergence of the first inflorescence, number of days for the inflorescence harvest, crop cycle, diameter of the flower stem, length of the flower stem, inflorescence length, plant high, number of tillers and productivity of flower stems. Chlorophyll and leaf area measurements were performed. The irrigation levels tested significantly influenced the number of days for the first inflorescence harvest, length of the flower stem and inflorescence length. The irrigation level of 150% ECA provided better results for the length of the flower stem, inflorescence length and for leaf area but without differences from 75%, 100% and 125% ECA. Thus, for the cultivation of the heliconia cv. Golden Torch in pot can be recommended the level corresponding from 75% to 150% ECA.

Floral management using the growth regulator paclobutrazol may be an alternative for promoting the uniformity of flowering and fruiting in West Indian cherry (Malpighia emarginata D.C.) plants. However, the effects of its use on fruit quality are still unknown. This study aimed to evaluate the effect of paclobutrazol doses on the fruit quality of M. emarginata. The experimental design was randomized blocks, in a 2 x 5 factorial arrangement, with three replications and three plants per plot, with the studied factors consisting of two M. emarginata cultivars ('Junko' and 'Flor Branca') and five paclobutrazol doses (0, 0.4, 0.8, 1.2 and 1.6 g a.i. m-1 of canopy diameter). The following variables were evaluated: fruit mass, fruit transverse and longitudinal diameters, pH, soluble solids content, titratable acidity, soluble solids/titratable acidity ratio and vitamin C content. The use of paclobutrazol, to some extent, promoted the increase of fruit mass, longitudinal diameter and soluble solids contents. The 'Junko' cultivar presented a higher vitamin C content than that for 'Flor Branca', and the maximum vitamin C contents were obtained with the paclobutrazol doses of 0.64 and 0.81 g a.i. m-1, respectively for the 'Junko' and 'Flor Branca' cultivars. None of the studied factors promoted differences for pH and fruit acidity.