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The Substâncias húmicas e formas de aplicação no enraizamento de estacas semilenhosas de oliveira
No full textThe objective of this work was to evaluate the rooting of semi - hardwood cuttings of olive trees using humic substances and their application form. Two experiments were conducted under conditions of screen with 30% retention of the radiation and in masonry bed, complete with sand. A low tunnel was built on the site, measuring 5 x 0.80 m and 0.55 m high, covered with transparent tarpaulin, and within the tunnel was an irrigation system such as intermittent misting. The first experiment was the rooting of cuttings of the cultivars Maria da Fé and Ascolano. The experimental design was randomized blocks, in a 2 x 5 factorial scheme. The second experiment consisted in the rooting of the two cultivars by means of three application forms of the commercial product SoloHumics® plus the control. The experimental design was randomized blocks in a 2 x 4 factorial scheme. Data were collected 75 days after assembly and some phytotechnical evaluations were performed. The cuttings of the cultivar Ascolano 315 presented the best rooting in the treatment with humic acids. The commercial product favored a greater average length of the highest root for the Maria da Fé cultivar and the fulvic acids favored Ascolano 315. The best method of application of humic substances occurred in the form of bed irrigation for the cultivar Maria da Fé.O objetivo do trabalho foi avaliar o enraizamento de estacas semilenhosas de oliveiras por meio de substancias húmicas e forma de aplicação. Foram conduzidos dois experimentos sob condições de telado com 30% de retenção da radiação e em canteiro de alvenaria, completo com areia. Sobre o canteiro foi construído um túnel baixo nas dimensões de 5 x 0,80 m e 0,55 m de altura, coberto com plástico transparente, dentro do túnel havia um sistema de irrigação como nebulização intermitente. O primeiro experimento foi o enraizamento de estacas das cultivares Maria da Fé e Ascolano. O delineamento experimental utilizado foi blocos casualizados, em esquema fatorial 2 x 5 com 3 repetições de 25 estacas. O segundo experimento constituiu-se no enraizamento das duas cultivares por meio de três formas de aplicação do produto comercial SoloHumics® mais a testemunha. O delineamento experimental foi de blocos casualizados em esquema fatorial 2 x 4. Os dados foram coletados 75 dias após a montagem e foram realizadas algumas avaliações fitotecnias. As estacas da cultivar Ascolano 315 apresentaram o melhor enraizamento no tratamento com ácidos húmicos. O produto comercial favoreceu maior comprimento médio da maior raiz para a cultivar Maria da Fé e os ácidos fúlvicos favoreceram para a Ascolano 315. O melhor método de aplicação de substâncias húmicas deu-se na forma de irrigação do leito para a cultivar Maria da Fé
Resíduos orgânicos e composto fermentado bokashi no desenvolvimento de mudas de couve-flor
No full textThe formation of seedlings reflects the culture\u27s performance, and the substrate may influence the obtainment of seedlings. Bokashi compost and organic residues can change substrate characteristics and influence seedling development. The present study aimed to analyze the development of cauliflower seedlings by adding bokashi-type fermented compost and agricultural residues to the substrate. The experiment was performed in a completely randomized design in a 5x2 factorial scheme, with five conditions of agricultural residues (control (no residues), coffee residue, yerba mate residue, corn residue, and residue mixture (coffee, yerba mate, and corn)) two conditions of bokashi addition (with (5%) and without) and 18 repetitions. The sowing of cauliflower was performed in polyethylene trays and kept in a protected environment for 30 days. Fresh and dry mass of shoots (stem and leaves), number of leaves per seedling, relative water content (RWC) in leaves, and leaf pigments were evaluated. Data analysis of variance and comparison of means done by the Tukey test, multivariate analysis, and linear correlation. The bokashi compost favored the development of cauliflower seedlings. However, the addition of agricultural residues demonstrated efficiency only when incorporated with bokashi. The use of the residue mixture rendered the best performance of the cauliflower seedlings by adding organic residues to the substrate.A formação de mudas apresenta reflexo sobre o desempenho da cultura, podendo ser influenciada pelo substrato utilizado. A utilização de composto bokashi e resíduos orgânicos pode alterar características do produto e influenciar no desenvolvimento das mudas. Dessa forma, o estudo teve como objetivo avaliar o efeito de resíduos orgânicos e composto fermentado bokashi no desenvolvimento de mudas de couve-flor. O experimento foi conduzido em delineamento inteiramente casualizado em esquema fatorial 5x2, sendo cinco condições de resíduos agrícolas (controle (sem resíduos), resíduo de café, resíduo de erva-mate, resíduo de milho e mistura de resíduos (café, erva-mate e milho)) duas condições de adição de bokashi (com (5%) e sem) e 18 repetições. A semeadura da couve-flor foi realizada em bandejas de polietileno, sendo mantidas em ambiente protegido durante 30 dias. Foram avaliadas a massa fresca e seca da parte aérea (caule e folhas), número de folhas por muda, conteúdo relativo de água (CRA) nas folhas e pigmentos foliares. Os dados foram submetidos à análise de variância, e comparação de médias pelo teste Tukey, análise multivariada e correlação linear. O composto bokashi melhorou o desenvolvimento das mudas de couve-flor. A adição dos resíduos agrícolas apresentou eficiência apenas quando incorporada com bokashi. Ao utilizar resíduos no substrato, o melhor desempenho foi obtido para utilização da mistura de resíduos
Influência de diferentes doses e fontes de fertilizante potássico na produção de abobrinha
No full textPotassium (K) is essential nutrient to the physiological and biochemical activities of plants, acting in the cation-anion balance, water movement, osmoregulation, and transference of energy. This study aimed to evaluate the yield response of the zucchini squash cultivar \u27Caserta\u27 to different doses and sources of potassium. The experiment was carried out under field conditions in a complete randomized block experimental design in a 6 x 2 factorial scheme, with six K2O doses (0, 50, 100, 150, 200, and 250 kg ha-1) and two sources (chloride and potassium sulfate), with four replications. The fruit mass, fruit length, number of fruits per plant, total and marketable fruit yields were evaluated. The results showed that the sulfate and potassium chloride sources promoted the maximum length and number of fruits per plant. K2O fertilization in the form of potassium sulfate promoted higher mass and total fruit yield. The doses of 108.41 and 130.78 kg ha-1 of K2O in the chloride and potassium sulfate sources provided the maximum marketable yield of fruits, with 22.84 and 27.0 t ha-1, respectively. Regardless of the source, potassium fertilization must be provided to increase the production parameters of the zucchini squash \u27Caserta\u27 cultivar
Produção de mudas de Euterpe precatoria Mart. em resposta a diferentes dosagens de nitrogênio e potássio
No full textThe success of açaí establishment as a monoculture is associated with the care regarding seedling quality and health. From this perspective, this study aimed to evaluate the influence of nitrogen and potassium to produce seedlings of Euterpe precatoria Mart. The experiment was set up in a randomized block design in a 5x5 factorial arrangement, with the first factor corresponding to nitrogen levels (0, 15, 30, 45, and 60 mg dm-3 of N) and the second factor consisting of the potassium levels (0, 40, 80, 120, and 160 mg dm-3 of K), aplit into 20, 40, and 40% of the total dosage. The following were evaluated 300 days after harvesting: seedling height, stem diameter, number of active leaves, dry root, shoot, and total mass, and the Dickson Quality Index. The data were subjected to univariate analysis and then to regression analysis. A significant effect was observed only for the N levels, with a positive linear response on all variables analyzed. Thus, the nitrogen levels influenced the growth and quality of E. precatoria seedlings 300 days after transplanting. Potassium fertilization for E. precatoria seedlings during the nursery phase was not responsive to any variable. In addition, there was no effect of the interaction between the N and K levels on the growth ofE. precatoria seedlings 300 days after transplanting, and seedlings subjected to increasing nitrogen levels wereresponsive, showing good morphological attributes.O sucesso para a implementação de açaizeiro solteiro em forma de monocultivo está atrelado ao cuidado referente a qualidade e sanidade da muda. Portanto, objetivou-se avaliar a influência de nitrogênio e potássio para a produção de mudas de Euterpe precatoria Mart. O experimento foi instalado em delineamento em blocos casualizados em esquema fatorial 5x5, sendo o primeiro fator as doses de nitrogênio (0, 15, 30, 45 e 60 mg dm-3 de N) e o segundo de potássio (0, 40, 80, 120 e 160 mg dm-3 de K), ambos aplicados de forma parcelada, 20, 40 e 40%. Aos 300 dias após a repicagem foram avaliados: altura da muda, diâmetro do coleto, número de folhas ativas, massa seca da raiz, da parte aérea e total e, posteriormente o índice de qualidade de Dickson. Os dados foram submetidos a análise univariada e posterior análise de regressão. Observou-se efeito significativo apenas para as dosagens de N, com resposta linear positiva para todas as variáveis analisadas. Desta forma, as doses de nitrogênio influenciam no crescimento e na qualidade de mudas de E. precatoria aos 300 dias após repicagem; a adubação potássica para mudas de E. precatoria na fase de viveiro não se mostrou responsiva para nenhuma variável; além disso, não se verificou interação entre as doses de N e K no crescimento de mudas de E. precatoria aos 300 dias após repicagem e mudas submetidas a doses crescentes de nitrogênio são responsivas, possuindo bons atributos morfológicos
Phenology and phyllochron of seven strawberry cultivars grown in substrate and greenhouse in the Brazilian subtropics
Get PDFKnowing the phenology and phyllochron of strawberry cultivars allows the establishment of phytotechnical managements aimed at enhancing the productive chain of this horticultural crop. Thus, the objective of this work was to investigate whether phenology and phyllochron differ among strawberry cultivars grown in substrate and greenhouse. The treatments were seven strawberry cultivars arranged in a randomized block design, with four replications. Leaf emission rate, occurrence and duration of phenological stages were evaluated. ‘Fronteras’ was considered the earliest to start fruiting, as it had the lowest phyllochron value, while ‘Albion’ was the latest. Through multivariate analysis, the formation of two groups among strawberry cultivars was observed according to their phenological characteristics. Group 1 gathered the five strawberry cultivars classified as having neutral-days in terms of flowering and group 2 was composed of the two short-day cultivars. It is concluded that, under the cultivation conditions of southern Brazil, ‘Fronteras’ is the earliest to start the fruit harvest, provided it is transplanted in May, and ‘Albion’ is the latest. Neutral-day cultivars have a shorter transplant cycle until the beginning of harvest, while short-day cultivars require a longer interval for this transition, with a prolonged vegetative period.Knowing the phenology and phyllochron of strawberry cultivars allows the establishment of phytotechnical managements aimed at enhancing the productive chain of this horticultural crop. Thus, the objective of this work was to investigate whether phenology and phyllochron differ among strawberry cultivars grown in substrate and greenhouse. The treatments were seven strawberry cultivars arranged in a randomized block design, with four replications. Leaf emission rate, occurrence and duration of phenological stages were evaluated. ‘Fronteras’ was considered the earliest to start fruiting, as it had the lowest phyllochron value, while ‘Albion’ was the latest. Through multivariate analysis, the formation of two groups among strawberry cultivars was observed according to their phenological characteristics. Group 1 gathered the five strawberry cultivars classified as having neutral-days in terms of flowering and group 2 was composed of the two short-day cultivars. It is concluded that, under the cultivation conditions of southern Brazil, ‘Fronteras’ is the earliest to start the fruit harvest, provided it is transplanted in May, and ‘Albion’ is the latest. Neutral-day cultivars have a shorter transplant cycle until the beginning of harvest, while short-day cultivars require a longer interval for this transition, with a prolonged vegetative period
Gladiolus production as a function of growing environment conditions: a scientometric analysis
Get PDFLately, an increase in the commercialization of gladiolus has been observed, making it necessary to know information that contributes to the optimization of its production. Such information can be obtained from the scientometric analysis. Thus, the objective of this work was to perform a scientometric analysis of the global scientific literature to quantify the studies on gladiolus and to specify in the Brazilian scientific literature the resultsof works on the cultivation environment. The scientometric analysis was performed in the Scopus database for the entire historical data series until the year 2021. A total of 1402 scientific papers published on gladiolus culture were obtained with an average publication rate equal to 0.62 papers year-1. These papers were mostlypublished as scientific articles in English language in journals focusing on horticulture and India is the countrywith the highest number of publications. About the cultivation environment, the studies conducted in Brazil indicate that the production of gladiolus should be carried out in periods that do not occur frosts and also for average air temperature below 35°C and soil humidity above 75% of field capacity. Despite the important results of these works, the global scientific literature still lacks more information that adequately assists in the increase of gladiolus production.Lately, an increase in the commercialization of gladiolus has been observed, making it necessary to know information that contributes to the optimization of its production. Such information can be obtained from the scientometric analysis. Thus, the objective of this work was to perform a scientometric analysis of the global scientific literature to quantify the studies on gladiolus and to specify in the Brazilian scientific literature the result
NPK combinations mitigate the deleterious effects of salt stress on the morphophysiology of West Indian Cherry
Get PDFUnder salt stress, plant growth and development are negatively affected due to physiological changes,requiring strategies such as fertilization management to minimize these effects. In this scenario, this study aimedto evaluate the effect of combinations of nitrogen, phosphorus, and potassium on the growth, leaf waterstatus, electrolyte leakage, and gas exchange of West Indian Cherry grown under water stress in the secondyear of production. The experiment was conducted in a protected environment in Campina Grande - PB.The treatments were distributed in a randomized block design with a 2 × 10 factorial arrangement with threereplications corresponding to two electrical conductivity levels of irrigation water– ECw (0.6 and 4.0 dS m-1)and ten combinations of fertilization with nitrogen, phosphorus, and potassium (80-100-100; 100-100-100; 120-100-100; 140-100-100; 100-80-100; 100-120-100; 100-140-100; 100-100-80; 100-100-120, and 100-100-140% of therecommendation in the second year of production). Irrigation with the ECw of 4.0 dS m-1 negatively affectedplant growth, the leaf water status, electrolyte leakage, and the leaf gas exchange of West Indian Cherry.However, the 40% increase (C4 -140-100-100% of the recommended N-P2O5-K2O level) in the nitrogen levelmitigated the deleterious effects of salt stress on the relative water content, internal CO2 concentration, and theCO2 assimilation rate of West Indian Cherry plants in the second year of production.Under salt stress, plant growth and development are negatively affected due to physiological changes,requiring strategies such as fertilization management to minimize these effects. In this scenario, this study aimedto evaluate the effect of combinations of nitrogen, phosphorus, and potassium on the growth, leaf waterstatus, electrolyte leakage, and gas exchange of West Indian Cherry grown under water stress in the secondyear of production. The experiment was conducted in a protected environment in Campina Grande - PB.The treatments were distributed in a randomized block design with a 2 × 10 factorial arrangement with threereplications corresponding to two electrical conductivity levels of irrigation water– ECw (0.6 and 4.0 dS m-1)and ten combinations of fertilization with nitrogen, phosphorus, and potassium (80-100-100; 100-100-100; 120-100-100; 140-100-100; 100-80-100; 100-120-100; 100-140-100; 100-100-80; 100-100-120, and 100-100-140% of therecommendation in the second year of production). Irrigation with the ECw of 4.0 dS m-1 negatively affectedplant growth, the leaf water status, electrolyte leakage, and the leaf gas exchange of West Indian Cherry.However, the 40% increase (C4 -140-100-100% of the recommended N-P2O5-K2O level) in the nitrogen levelmitigated the deleterious effects of salt stress on the relative water content, internal CO2 concentration, and theCO2 assimilation rate of West Indian Cherry plants in the second year of production.
Quality of yellow passion fruit as a function of irrigation, artificial pollination, and protected cultivation
Get PDFPassion fruit stands out among the fruit crops of economic expression in Brazil due to the medicinal, cosmetic, and organoleptic properties of its fruits, having great acceptance by consumers. In this scenario, this study aimed to evaluate the physical and chemical quality of organic yellow passion fruit as a function of pollination combined with irrigation and protected cultivation. The experimental design was in randomized blocks arranged in split plots (2 x 2 x 2), with eight treatments and four replications containing four plants per experimental unit. The protected environment was set up on the upper part of each espalier, consisting of a 100μ transparent plastic film used as cover. Irrigation was performed using a micro-sprinkler system, and pollination was either manual or natural (entomophilic). The following parameters were evaluated: soluble solids content; total titratable acidity; ratio of soluble solids to titratable acidity; gross pulp yield; and juice yield. Fruits were also classified according to their physical appearance by counting the number of fruits with slight, severe, or no damage, in addition to the equatorial fruit diameter. These assessments were carried out in two periods: crop season 1 (January to August 2019) and crop season 2 (September 2019 to August 2020). The results revelated that the cultivation system combining rainfed conditions, plastic protection of plants, and artificial pollination produced fruits with larger diameters and more class 5 fruits. Moreover, the cropping systems did not influence the gross pulp yield, juice yield, titratable acidity, soluble solids, and the ratio of soluble solids to titratable acidity.Among the fruit crops of economic expression in Brazil, the passion fruit stands out for the medicinal, cosmetic and organoleptic properties of its fruits, having great acceptance by consumers. Because of this, the objective was to evaluate the physical and chemical quality of yellow passion fruit fruits under organic system as a function of pollination combined with irrigated and protected cultivation. The experimental design was in randomized blocks in divided plots (2 x 2 x 2) with eight treatments and four replications containing four plants per experimental unit. The protected environment was installed on the upper part of each espalier, consisting of a 100 m transparent additive plastic film as material for the covering. Irrigation was of the micro sprinkler type and manual or natural (entomophilic) pollination. The following were evaluated: soluble solids content; total titratable acidity; ratio; raw pulp yield; juice yield; In the classification of the fruits - the physical appearance was analyzed, counting the amount of fruits that presented light, serious or without damages and the equatorial diameter of the fruits. These assessments were carried out in two periods: crop 1 (January to August 2019) and crop 2 (September 2019 to August 2020). It is concluded that: the cultivation system combining rainfed, plastic protection of plants and artificial pollination produces fruits with larger diameter and larger percentage of fruits in gauge 5; the raw pulp and juice yield, titratable acidity, soluble solids and ratio are not influenced by the cultivation systems
Salicylic acid does not alleviate salt stress on physiological indicators and growth of guava
Get PDFIn the semi-arid region, the quality of water for irrigation stands out as a limiting factor for the expansion ofagriculture. Thus, it is extremely important to search for alternatives that minimize the effects of salt stress onplants. Foliar application of salicylic acid stands out among these strategies. In this context, the objective ofthis study was to evaluate the gas exchange, photosynthetic pigments, and growth of guava as a function ofirrigation water salinity and exogenous application of salicylic acid in the post-grafting stage. The experimentwas conducted under greenhouse conditions, in a randomized block experimental design, in a 2 × 4 facto rialscheme, corresponding to two levels of electrical conductivity of irrigation water (0.6 and 3.2 dS m-1) and fourconcentrations of salicylic acid (0; 1.2; 2.4 and 3.6 mM), with three replicates. Irrigation with water of 3.2 dS m-1caused reductions in transpiration, CO2 assimilation rate, instantaneous water use efficiency and instantaneouscarboxylation efficiency of guava, at 150 days after transplanting. Water with electrical conductivity of 3.2 dSm-1 reduced the growth in stem diameter and the absolute and relative growth rates, as well as the relativewater content, and chlorophyll a and b contents of guava plants. The interaction between water salinity levelsand salicylic acid concentrations did not influence the physiological indices and growth of guava in the postgraftingphase
Mathematical models and X-ray image analysis in the drying of cumbaru seeds
Get PDFThe cumbaru (Dipteryx alata Vog.) is a native species of the Cerrado. The species is of great economicexpression for family farming. This study aimed to determine the drying curves and fit mathematical models tothe experimental data obtained in the drying of cumbaru seeds. Furthermore, it aimed to define the best-fittedmodel and correlate the damage caused by the drying process through X-ray images. The Dipteryx alata Vog.seeds were obtained from fruits collected from 20 matrices in the municipality of Cáceres, in the state of MatoGrosso (MT), approximately 255 days after anthesis. The seeds were extracted and stored for 15 days until theyreached hygroscopic equilibrium and a 14.5% water content. Drying was conducted in a continuous airflowdryer with an approximate temperature of 40° and a constant airflow velocity of 2.5 m/s. The experimental datawere fitted to twelve mathematical models. The values of the coefficients of determination (R2), the relativemean error (P), and the estimated mean error (SE) were used to check the models’ fit degree. After drying,40 seeds from each treatment were subjected to X-ray testing using the Faxitron MX-20 DC 12 equipment. TheMidilli mathematical model was the best fit for the experimental data. The X-ray images showed no cracks orany other damage caused by the drying process.The cumbaru (Dipteryx alata Vog.) is a native species of the Cerrado. The species is of great economic expression for family farming. This study aimed to determine the drying curves and fit mathematical models to the experimental data obtained in the drying of cumbaru seeds. Furthermore, it aimed to define the best-fitted model and correlate the damage caused by the drying process through X-ray images. The Dipteryx alata Vog. seeds were obtained from fruits collected from 20 matrices in the municipality of Cáceres, in the state of Mato Grosso (MT), approximately 255 days after anthesis. The seeds were extracted and stored for 15 days until they reached hygroscopic equilibrium and a 14.5% water content. Drying was conducted in a continuous airflow dryer with an approximate temperature of 40° and a constant airflow velocity of 2.5 m/s. The experimental data were fitted to twelve mathematical models. The values of the coefficients of determination (R2), the relative mean error (P), and the estimated mean error (SE) were used to check the models’ fit degree. After drying, 40 seeds from each treatment were subjected to X-ray testing using the Faxitron MX-20 DC 12 equipment. The Midilli mathematical model was the best fit for the experimental data. The X-ray images showed no cracks or any other damage caused by the drying process