Potencial produtivo e qualidade de pitaia com fertilização nitrogenada

The objective of this work was to determine adequate rates of nitrogen to reach satisfactory yield, fruit quality, and cladode nutrient content in three species of pitaya. The experimental design was carried out in randomized complete blocks, with a 3×4 factorial arrangement. The treatments consisted of the following pitaya species and N rates: Selenicereus megalanthus, Hylocereus undatus, and Hylocereus polyrhizus; and 0, 50, 100, and 200 g N per plant, in the first production cycle (2016/2017 crop season) and 50, 100, 200, and 300 g N per plant, in the second and third production cycles (2017/2018 and 2018/2019 crop seasons). Nitrogen fertilization increased the yield, fruit quality, and cladode nutrient content of the species. In the third production cycle, yield was 1.18 Mg ha-1 for S. megalanthus, 10.87 Mg ha-1 for H. undatus, and 10.4 Mg ha-1 for H. polyrhizus in open pollination. The highest yield is obtained with 300 g N per plant for S. megalanthus. For H. polyrhizus and H. undatus the rates are from 170 to 190 g N per plant, supplemented with P and K.O objetivo deste trabalho foi determinar doses adequadas de nitrogênio para alcançar produtividade, qualidade das frutas e teor de nutrientes satisfatórios em cladódios de três espécies de pitaia. O delineamento experimental foi feito em blocos ao acaso, com arranjo fatorial 3×4. Os tratamentos consistiram das seguintes espécies de pitaia e doses de N: Selenicereus megalanthus, Hylocereus undatus e Hylocereus polyrhizus; e 0, 50, 100 e 200 g de N por planta, no primeiro ciclo de produção (safra 2016/2017) e 50, 100, 200 e 300 g de N por planta, no segundo e terceiro ciclos de produção (safras 2017/2018 e 2018/2019). A fertilização com N aumentou a produtividade, a qualidade das frutas e o teor de nutrientes nos cladódios das espécies. No terceiro ciclo de produção, a produtividade foi de 1,18 Mg ha-1 para S. megalanthus, 10,87 Mg ha-1 para H. undatus e 10,4 Mg ha-1 para H. polyrhizus em polinização aberta. A maior produtividade é obtida com 300 g de N por planta para S. megalanthus. Para H. polyrhizus e H. undatus, as doses são de 170 a 190 g de N por planta, complementadas com P e K

Increase of nutrients export and production of pitaya whit potassium fertilization

Characterization works of pitayas show that the potassium (K) is the nutrient most exported, thus, influences in the productivity and quality of this fruit. However, these researches do not report the nutrients export by pitaya's associating the fertilization carried out in the orchard, information that is relevant to make the nutrients reposition adequate at the time of fertilization. The research was carried out to evaluate the supply of K2O in the export of nutrients and productivity of the Hylocereus undatus and Hylocereus polyrhizus pitaya species. The analysis was carried out in the mature fruits harvested in two harvests. Potassium fertilization was performed at doses of 0; 50; 100 and 200 g of K2O per plant. Nutrient export per ton of fruit was calculated from the determination of the nutrient levels and the dry matter of the pitaya pulp. The export of nutrients by the pitaya of the species H. undatus and H. polyrhizus occurs in the following order: K>N>P>Ca>Mg> and Mn>Fe>Cu>Zn>B. These species of pitaya have similar nutritional requirements, enabling them to be receive same fertilization management. The amount of nutrients exported was higher in plants fertilized with potassium due to the higher productivity achieved. Orchards of pitaya that reach high productivity require a greater quantity of nutrients, due to the increase export by the fruits.Characterization works of pitayas show that the potassium (K) is the nutrient most exported, thus, influences in the productivity and quality of this fruit. However, these researches do not report the nutrients export by pitaya's associating the fertilization carried out in the orchard, information that is relevant to make the nutrients reposition adequate at the time of fertilization. The research was carried out to evaluate the supply of K2O in the export of nutrients and productivity of the Hylocereus undatus and Hylocereus polyrhizus pitaya species. The analysis was carried out in the mature fruits harvested in two harvests. Potassium fertilization was performed at doses of 0; 50; 100 and 200 g of K2O per plant. Nutrient export per ton of fruit was calculated from the determination of the nutrient levels and the dry matter of the pitaya pulp. The export of nutrients by the pitaya of the species H. undatus and H. polyrhizus occurs in the following order: K>N>P>Ca>Mg> and Mn>Fe>Cu>Zn>B. These species of pitaya have similar nutritional requirements, enabling them to be receive same fertilization management. The amount of nutrients exported was higher in plants fertilized with potassium due to the higher productivity achieved. Orchards of pitaya that reach high productivity require a greater quantity of nutrients, due to the increase export by the fruits

Ácido indolbutírico e polímero hidroabsorvente no enraizamento de estacas de amoreira-preta

The search for alternatives to allow the production of fruit seedlings is constant. Nowadays, the preference is to form the plants in containers because the advantages in relation to good root development and time for obtaining of seedlings, by using substrate prepared in a controlled environment. The study was carried out with the aim of evaluating the substrate formulation with the hydrogel polymer in rooting of blackberry cv. Brazos treated with IBA. There were used the completely randomized design in a 4 x 2 factorial arrangement with four replications and six cuttings per plot, the factors were the hydrogel polymer concentrations (Suprágua®) : 0, 3, 6 and 9 g L-1 and indolbutiric acid (IBA): 0 and 3000 mg L-1. After 90 days were evaluated the following variables: rooting percentage, the number of roots, shoots and leaves, root and shoot length (cm). Treatment of cuttings with IBA did not influence the rooting. The incorporation to 5.6 g L-1 hydrogel polymer increased rooting and better seedling development. The roots number favored the shoot length and the leaves issue in cuttings of blackberry cv. Brazos.A busca por alternativas para viabilizar o processo de produção de mudas frutíferas é constante. Atualmente, a preferência é formar as mudas em recipientes devido às vantagens oferecidas em relação ao bom desenvolvimento do sistema radicular e a época de obtenção das mudas, por utilizar substratos preparados em ambiente controlado. O trabalho foi realizado com o objetivo de avaliar a formulação do substrato com o polímero hidroabsorvente no enraizamento da amoreira preta cv. Brazos tratada com o ácido indolbutírico. Foi utilizado o delineamento experimental inteiramente casualizado, em esquema fatorial 4 x 2, com quatro repetições e seis estacas por parcelas, sendo os fatores quatro as doses polímero hidroabsorvente (Suprágua®): 0, 3, 6 e 9 g L-1 e duas concentrações de ácido indolbutírico (AIB): 0 e 3000 mg L-1. Após 90 dias foram avaliadas as seguintes variáveis: percentual de enraizamento, o número de raízes, de brotações e de folhas, o comprimento das raízes e da parte aérea (cm). O tratamento de estacas com ácido indolbutírico (AIB) não influenciou no enraizamento. A incorporação ao substrato de 5,6 g L-1 de polímero hidroabsorvente proporcionou maior enraizamento e melhor desenvolvimento das mudas. O número de raízes favoreceu o comprimento da parte aérea e a emissão de folhas nas estacas de amoreira-preta cv. Brazos

Commercial productivity and quality of pitaya as a function of number of fruits per cladode

ABSTRACT Increasing orchard productivity is among the main objectives of pitaya producers. However, the commercial productivity may reduce due to reduction of fruit size as a function of the high amount per plant. This study evaluated the influence of the number of fruit per cladode in commercial productivity and in quality of fruits of two pitaya species at different harvest times. The experiment was carried out in a six-year-old orchard formed by the species Selenicereus undatus and Hylocereus polyrhizus. At each flowering time, the number of fruits set per cladode was counted and plants with two, four, five and six fruits per cladode were selected, and surplus fruits removed. The evaluations followed a split plot design over time, with the main plot as the number of fruit per cladode and the subplot as the harvest seasons: December, February and March, with four replicates and one plant per plot. Plants grown with two fruits per cladode presented the highest percentage of fruits with commercial size and commercial productivity. Both species showed fruits with commercial size in the first harvest of the cycle (December). S. undatus fruits classified as Class I and H. polyrhizus fruits classified as Extra and Class I showed the best quality

Teores de carboidratos e indução do florescimento em mudas de oliveira submetida à aplicação de paclobutrazol

The paclobutrazol (PBZ) application can slow growth and increase flowering in certain fruit species by reducing root growth and gibberellins synthesis. In addition, other plant characteristics can be influenced by the PBZ application as carbohydrates concentrations. This work was carried out aiming to evaluate the relationship between the carbohydrates concentration in leaf and reproductive development in olive tree through the PBZ application. Three-year-old olive plants of cultivar Arbequina were grown in 20 liters pots outdoors. We used five doses PBZ: 2.0, 4.0, 8.0 and 12.0 mL plant-1 distributed in a completely randomized design with four replications and two plants per plot were applied to soil. The evaluation of reproductive development and carbohydrates concentration was carried during the flowering season of plants. The PBZ application promoted to increase in flower racemes number. The greater carbohydrate accumulation in leaves was observed in plants submitted to PBZ application.A aplicação de paclobutrazol (PBZ) pode retardar o crescimento e aumentar o florescimento em determinadas espécies frutíferas, mediante redução do crescimento das raízes e síntese de giberelinas. Além disso, outras características da planta podem ser influenciadas pela aplicação de PBZ como as concentrações de carboidratos. Este trabalho foi conduzido com o objetivo de verificar a relação entre a concentração de carboidratos nas folhas e o desenvolvimento reprodutivo na oliveira mediante a aplicação de PBZ. Plantas da cultivar Arbequina com três anos de idade foram cultivadas em vasos de 20 litros em ambiente aberto. Utilizou-se cinco doses de PBZ: 0; 2,0; 4,0; 8,0 e 12,0 mL planta-1 distribuídas em delineamento inteiramente casualizado com quatro repetições e duas plantas por parcela, aplicadas via solo. A avaliação do desenvolvimento reprodutivo e das concentrações de carboidratos foi realizada na época de floração das plantas. A aplicação de PBZ proporcionou aumento no número de rácimos florais. O maior teor de carboidratos acumulado nas folhas foi observado nas plantas submetidas à aplicação de PBZ.&nbsp

Nutrient accumulation at the initial growth of pitaya plants according to phosphorus fertilization

The knowledge about the amount of nutrient uptake in pitaya plants helps the balanced fertilizer recommendation for the crop, providing adequate nutrition and contributing to the maximum expression of this species potential. This research was carried out in order to evaluate the growth, nutrient accumulation and efficiency of absorption, transportation and use of P by pitaya according to phosphorus fertilization. A randomized blocks design was used, with five doses of P (0 mg dm-3, 20 mg dm-3, 40 mg dm-3, 80 mg dm-3 and 160 mg dm-3) incorporated into the soil, with four replications, three pots per plot and one cutting per pot. Differences in the nutrient accumulation of all doses were evident in the pitaya shoots and roots, as well as in the efficiency of absorption, transport and use of P, according to phosphorus fertilization. The nutrient accumulation in the pitaya roots was ranked in the following order: N > K > Ca > S > P > Mg > Fe > Mn > Zn > B ≥ Cu. For the shoots, the order was: K > N > Ca > S > Mg > P > Mn > Fe > Zn > B ≥ Cu. The initial growth of pitaya plants was maximum with 81 mg dm-3 of P, in a Red-Yellow Dystrophic Latosol. The application of 44-67 mg dm3 of P to the soil promoted the highest accumulation of macro and micronutrients in the pitaya

Carbohydrate levels in the leaves and production consistency of the Ponkan tangerine when thinned out with Ethephon

Management practices that maintain carbohydrate reserves in tangerines are necessary in order to ensure good yields. This experiment was carried out with the object of evaluating the levels of carbohydrates in the leaves, and consistency in the production of the Ponkan tangerine (Citrus reticulata Blanco) when subjected to chemical thinning with five concentrations of Ethephon for three consecutive years. The Ponkan tangerine evaluated had been grafted onto Rangpur lime (Citrus limonia Osbeck), cultivated with a spacing of 6.0 x 3.0 m and were 12 years old. The Ethephon concentrations tested were: 0; 200; 400; 600 and 800 mg L-1, applied in January of 2009; 2010 and 2011, when the fruits were of 25 to 30mm in transverse diameter. The experimental design was of randomized blocks, with four blocks and four plants per plot. The levels of soluble leaf carbohydrate, starch and total carbohydrates were evaluated during flowering and harvesting. Fifteen days after application of the concentrations, the percentage of thinning was evaluated. Production, pending load and alternate bearing were evaluated when harvesting. Chemical thinning with Ethephon favors the maintaining of leaf carbohydrates in the Ponkan tangerine. The most effective concentration in reduncing the alternate bearing in the Ponkan tangerine is 600 mg L-1 of Ethephon

Leaf carbohydrates during flowering and early growth stages of fruitlets in 'Ponkan' mandarin tree

O objetivo deste trabalho foi avaliar os teores de carboidratos foliares em tangerineira 'Ponkan' (Citrus reticulata), durante o pleno florescimento e os estádios iniciais de crescimento dos frutilhos, e identificar a melhor época para realização do raleio químico. O experimento foi realizado durante dois anos de produção (2009/2010 e 2010/2011), com quatro épocas de amostragem de folhas: 0, 30, 60 e 90 dias após o pleno florescimento. Utilizou-se o delineamento de blocos ao acaso, com parcelas subdivididas no tempo, quatro repetições e quatro plantas por parcela. Para determinar a utilização dos carboidratos pelas plantas, foram avaliados os teores de açúcares solúveis, açúcares redutores e amido na matéria seca das folhas. Nas mesmas épocas de amostragem foliar, o tamanho dos frutilhos também foi determinado. Os teores foliares de carboidratos solúveis aumentam e os de amido diminuem entre 35 e 50 dias após o pleno florescimento. No final da fase de fixação dos frutilhos, a partir dos 50 dias após o pleno florescimento, os teores de açúcares solúveis nas folhas diminuem. A melhor época para a realização do raleio químico em tangerineira 'Ponkan' é logo após a fase de queda fisiológica, quando os frutilhos atingirem cerca de 18 mm de diâmetro, aos 50 dias após o pleno florescimento.The objective of this work was to evaluate the levels of carbohydrates in the leaves of 'Ponkan' mandarin tree (Citrus reticulata), during full flowering and early growth stages of fruitlets, and to identify the best time to perform chemical thinning. The experiment was carried out for two production years (2009/2010 and 2010/2011), with four sampling times of leaves: 0, 30, 60, and 90 days after full flowering. A randomized complete block design, split‑plotted in time with four replicates and four plants per plot, was used. To determine the use of carbohydrates by plants, the contents of soluble sugars, reducing sugars, and starch in the dry matter of leaves were evaluated. At the same leaf sampling times, fruitlet size was also determined. Leaf contents of soluble carbohydrates increase and the ones of starch decrease between 35 and 50 days after full flowering. At the end of the fruit setting phase, from the 50th day after full flowering, the contents of soluble sugars in leaves reduce. The best time to perform chemical thinning in 'Ponkan' mandarin tree is soon after the physiological drop phase, when the fruitlets reach around 18 mm, at the 50th day after full flowering