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Desempenho de cultivares de manjericão fertigadas com soluções nutritivas salinizadas: Estresse salino em manjericão
No full textABSTRACT: The aim of this study was to evaluate the performance of basil cultivars fertigated with saline nutrient solutions in semi-hydroponic cultivation. The experiment was carried out in a greenhouse, following a randomized block design, in a 5 x 3 factorial scheme, with five basil cultivars (Grecco a Palla, Alfavaca Basilicão, Alfavaca Verde, Lemoncino and Roxo) and three salinities of the nutrient solution (2.0, 3.5 and 5.0 dS m-1), with three replications, with the experimental portion represented by three pots containing 3.0 dm3 of coconut fiber and one plant in each. At 60 days after transplanting, plants were evaluated for plant height, number of leaves, number of stems and inflorescence, length of inflorescences, stem diameter, dry mass (leaves, stems, inflorescences and total), leaf area, specific leaf area, leaf area ratio, leaf succulence and the salinity tolerance index. In general, there were different responses between cultivars regarding salinity. Fertigation using high-salinity water promotes changes in the growth of sensitive basil cultivars. The cultivars Alfavaca Basilicão, Alfavaca Verde and Roxo were tolerant to all tested saline levels (2.0, 3.5 and 5.0 dS m-1), while the cultivars Grecco to Palla and Lemoncino were tolerant until the salinity of 3;5 dS m-1.RESUMO: Objetivou-se avaliar o desempenho de cultivares de manjericão fertigadas com soluções nutritivas salinizadas em cultivo semi-hidropônico. O experimento foi conduzido em casa de vegetação, seguindo o delineamento experimental de blocos casualizados, em esquema fatorial 5 x 3, sendo cinco cultivares de manjericão (Grecco a Palla, Alfavaca Basilicão, Alfavaca Verde, Lemoncino e Roxo) e três salinidades da solução nutritiva (2,0; 3,5 e 5,0 dS m-1), com três repetições, sendo a parcela experimental representada por três vasos contendo 3,0 dm3 de fibra de coco e uma planta em cada. Aos 60 dias após o transplantio as plantas foram avaliadas quanto à altura de plantas, número de folhas, número de hastes e de inflorescência, comprimento de inflorescências, diâmetro do caule, massa seca (folhas, hastes, inflorescências e total), área foliar, área foliar especifica, razão de área foliar, suculência foliar e o índice de tolerância a salinidade. De forma geral, houveram diferentes respostas entre as cultivares com relação a salinidade. A fertirrigação usando água de alta salinidade promove alterações no crescimento das cultivares sensíveis de manjericão. As cultivares Alfavaca Basilicão, Alfavaca Verde e Roxo foram tolerantes a todos níveis salinos testados (2,0; 3,5 e 5,0 dS m-1), enquanto as cultivares Grecco a Palla e Lemoncino foram tolerantes até a salinidade de 3,5 dS m-1
Physicochemical and functional characteristics of peach cv. Esmeralda fertilized with different doses of nitrogen
Get PDFThe aim of this study was to evaluate the physicochemical and functional characteristics of fruits yielded bypeach trees which were fertilized with different doses of nitrogen. The experiment, which was installed in 2014.It had a randomized complete block design with four replicates. The nitrogen rates applied were 0, 40, 80,120, and 160 kg N per hectare. Fruits were harvested in four crops in a row (2014, 2015, 2016, and 2017). Theparameters were evaluated: soluble solids, pH, titratable acidity, epidermis and pulp firmness, attributes of pulpcolor, carotenoids, phenolic compounds, and antioxidant activity. Responses were only related to luminosity inthe first crop. However, N fertilization influenced not only the soluble solid content, pH and chroma in the secondcrop but also all attributes of color in the third crop. SS, pH, ºHue and chroma differed among treatments inthe fourth crop. The more N in the first three crops, the more carotenoids. Phenolic compounds decreasedsignificantly in the 2016 crop whereas antioxidant activity diminished in both the 2015 and 2016 crops. Eventhough an ideal dose of N cannot be recommended due to high variation in attributes in the years underevaluation, it is needed because of other factors, such as weat her.The aim of this study was to evaluate the physicochemical and functional characteristics of fruits yielded bypeach trees which were fertilized with different doses of nitrogen. The experiment, which was installed in 2014.It had a randomized complete block design with four replicates. The nitrogen rates applied were 0, 40, 80,120, and 160 kg N per hectare. Fruits were harvested in four crops in a row (2014, 2015, 2016, and 2017). Theparameters were evaluated: soluble solids, pH, titratable acidity, epidermis and pulp firmness, attributes of pulpcolor, carotenoids, phenolic compounds, and antioxidant activity. Responses were only related to luminosity inthe first crop. However, N fertilization influenced not only the soluble solid content, pH and chroma in the secondcrop but also all attributes of color in the third crop. SS, pH, ºHue and chroma differed among treatments inthe fourth crop. The more N in the first three crops, the more carotenoids. Phenolic compounds decreasedsignificantly in the 2016 crop whereas antioxidant activity diminished in both the 2015 and 2016 crops. Eventhough an ideal dose of N cannot be recommended due to high variation in attributes in the years underevaluation, it is needed because of other factors, such as weat her
Resistance to whitefly mediated by the Mi gene, acylsugars, and zingiberene in tomato
Get PDFThis study aimed to quantify and compare the effects of Mi gene, high leaf levels of acylsugars (AA), and zingiberene (ZGB) individually and in combination, regarding resistance of tomato lines to Bemisia argentifolii. The experiment included 21 genotypes selected simultaneously for high AA and ZGB content, cloned through rooting of axillary shoots with homogeneous sizes, and seven control lines produced from seeds, including 2 genotypes rich in AA (TOM-687 and TOM-688), two genotypes rich in ZGB (TOM-703 and TOM-704), and three lines with low levels of allelochemicals (cv. Santa Clara, TOM-584, and TOM-684), where the TOM-684 line carried the Mi gene. The experiment was conducted in a greenhouse using a randomized complete block design, comprising 28 treatments with 4 replications and 1 plant per plot. The AA and ZGB-rich lines showed higher resistance compared to the other control lines with low levels of allelochemicals, but the TOM-684 control line carrying the Mi gene was more resistant than the non-carriers (\u27Santa Clara\u27 and TOM-584). The level of resistance conferred by ZGB was similar to that presented by AA. Both ZGB and AA provided higher levels of resistance compared to the Mi gene. The clones selected for both ZGB and AA simultaneously exhibited lower numbers of eggs and nymphs compared to the susceptible controls and were more resistant than the TOM-684 treatment. Overall, the clones even outperformed the lines rich in only one of the allelochemicals, demonstrating a synergistic effect between AA and ZGB for resistance when combined in the same tomato line.This study aimed to quantify and compare the effects of Mi gene, high leaf levels of acylsugars (AA), and zingiberene (ZGB) individually and in combination, regarding resistance of tomato lines to Bemisia argentifolii. The experiment included 21 genotypes selected simultaneously for high AA and ZGB content, cloned through rooting of axillary shoots with homogeneous sizes, and seven control lines produced from seeds, including 2 genotypes rich in AA (TOM-687 and TOM-688), two genotypes rich in ZGB (TOM-703 and TOM-704), and three lines with low levels of allelochemicals (cv. Santa Clara, TOM-584, and TOM-684), where the TOM-684 line carried the Mi gene. The experiment was conducted in a greenhouse using a randomized complete block design, comprising 28 treatments with 4 replications and 1 plant per plot. The AA and ZGB-rich lines showed higher resistance compared to the other control lines with low levels of allelochemicals, but the TOM-684 control line carrying the Mi gene was more resistant than the non-carriers (\u27Santa Clara\u27 and TOM-584). The level of resistance conferred by ZGB was similar to that presented by AA. Both ZGB and AA provided higher levels of resistance compared to the Mi gene. The clones selected for both ZGB and AA simultaneously exhibited lower numbers of eggs and nymphs compared to the susceptible controls and were more resistant than the TOM-684 treatment. Overall, the clones even outperformed the lines rich in only one of the allelochemicals, demonstrating a synergistic effect between AA and ZGB for resistance when combined in the same tomato line
Porta-enxerto e intensidade da poda de inverno para pessegueiro ‘Maciel’
No full textWinter pruning has been a common practice in peach. Twig topping has been associated with it, but this practice has been used at the same intensity, regardless of the cultivar. Therefore, this study aimed at evaluating productive behavior and quality of ‘Maciel’ peach grafted on ‘Capdeboscq’ and ‘Okinawa’ (P. persica) as rootstocks, when they were submitted to different twig topping intensities in winter pruning. The following three pruning intensities were evaluated: short pruning, when 2/3 of the productive twig was removed; long pruning, when 1/3 of the twig was removed; and pruning with no topping, when twigs were kept integral. Effective fructification is lower when ‘Maciel’ peach trees are submitted to short pruning, but it leads to fruit with higher weight and flesh firmness, besides larger diameters. Pruning with no twig topping and long pruning increased the fruit number and yield per tree. Not only fruit weight, diameter and soluble solid content, but also yield per tree of ‘Maciel’ peach are affected by ‘Capdeboscq’ and ‘Okinawa’, regardless of the intensity of twig topping throughout pruning. Higher concentration of soluble solids was found in peaches grafted in Okinawa. While the highest production was verified with the use of the ‘Capdeboscq’ rootstock
Morphological analysis and chlorophyll index of bell pepper cultivars under protected cultivation
Get PDFBell pepper is one of the vegetables that most contributes to the horticultural economy of the state of Para, Brazil, although the state has a low production of this vegetable. The objective of this study was to evaluate the adaptability of bell pepper (Capsicum annuum L.) cultivars grown in protected cultivation under the edaphoclimatic conditions of southeastern state of Para. The experiment was conducted at the Federal Rural University of Amazonia. A randomized block experimental design was used, with four replications. The treatments consisted of 9 bell pepper cultivars: Itapua 501, Yolo Wonder, Chapeu de Bispo Cambuci, Proveito, Amarelo SF 134, Rubi Gigante, Amarelo Alegria, All Big, and Amarelo Satrapo Sais. The parameters analyzed were: plant height (cm); number of fruits per plant; fruit weight (g); transversal (mm) and longitudinal diameters of fruits (mm); leaf area (cm²), width (cm), length (cm), perimeter (cm), and ratio (cm); and chlorophyll a, chlorophyll b, and total chlorophyll. The cultivar Amarelo Satrapo showed greater adaptability to cultivation in the studied region, presenting higher fruit weight, yield, and transversal diameter, leaf area and length, and good morphophysiological development. The cultivars Itapua 501, Amarelo SF 134, and Rubi Gigante showed good performances for morphophysiological parameters. The cultivars that presented the highest chlorophyll indices were Proveito, Itapua 501, All Big, and Amarelo Satrapo. The cultivar Amarelo Satrapo presented the highest adaptation to the climate conditions of southeastern Para.Bell pepper is one of the vegetables that most contributes to the horticultural economy of the state of Para, Brazil, although the state has a low production of this vegetable. The objective of this study was to evaluate the adaptability of bell pepper (Capsicum annuum L.) cultivars grown in protected cultivation under the edaphoclimatic conditions of southeastern state of Para. The experiment was conducted at the Federal Rural University of Amazonia. A randomized block experimental design was used, with four replications. The treatments consisted of 9 bell pepper cultivars: Itapua 501, Yolo Wonder, Chapeu de Bispo Cambuci, Proveito, Amarelo SF 134, Rubi Gigante, Amarelo Alegria, All Big, and Amarelo Satrapo Sais. The parameters analyzed were: plant height (cm); number of fruits per plant; fruit weight (g); transversal (mm) and longitudinal diameters of fruits (mm); leaf area (cm²), width (cm), length (cm), perimeter (cm), and ratio (cm); and chlorophyll a, chlorophyll b, and total chlorophyll. The cultivar Amarelo Satrapo showed greater adaptability to cultivation in the studied region, presenting higher fruit weight, yield, and transversal diameter, leaf area and length, and good morphophysiological development. The cultivars Itapua 501, Amarelo SF 134, and Rubi Gigante showed good performances for morphophysiological parameters. The cultivars that presented the highest chlorophyll indices were Proveito, Itapua 501, All Big, and Amarelo Satrapo. The cultivar Amarelo Satrapo presented the highest adaptation to the climate conditions of southeastern Para
Produção de mudas de rosas do deserto sob diferentes técnicas de cultivo
No full textDesert roses have gained notoriety in the ornamental market; however, the use of locally produced substrates isdiverse. Three experiments were carried out using a completely randomized design, with treatments arranged ina 3x4 factorial. Physical and chemical analyses were carried out for the following substrates: carnauba bagana,carbonized rice husk, decomposed babassu stem, and soil. Experiment 1: three sowing depths, D1: 0mm, D2:5mm and D3: 10 mm, combined with four substrates. Experiment 2: three substrates combined with four shadingscreens: thermal reflector, white shading, black shading and open sky. Experiment 3: three substrates combined with four irrigation levels: 100, 75, 50, and 25%. Measurements were made in the three experiments and datawere tested by analysis of variance using the “F” test, at the levels of 1% and 5%. Regression and averages wereexplored using Tukey’s test. It was concluded that the seedlings developed better under a level of 10 mm andsubstrate with 100% carnauba bagana, in association with an outdoor environment, and water levels between50 and 75% of pot capacity.A rosa do deserto tem ganhado notoriedade no mercado ornamental de flores por ser plantas belíssimas e de fácil manejo, entretanto, ainda são poucas as informações sobre o cultivo da espécie. Tendo em vista essa problemática, objetivou-se avaliar substratos formulados a base de bagana de carnaúba (Copernicia prunifera Mill.), casca de arroz carbonizada (Oryza sativa L.), caule decomposto de babaçu (Attalea speciosa) e solo, com diferentes profundidades de semeadura, tipos de sombreamento e lâminas de irrigaçãoara produção de mudas de Adenium obesum . Foram adotados delineamento inteiramente casualizado em esquema fatorial 4x3. Como variáveis avaliadas: germinação, índice de velocidade de emergência, altura da planta, altura do caudex, número de folhas, diâmetro do caule, diâmetro do caudex, comprimento radicular, massa seca e fresca das partes aéreas e raiz, volume da raiz e índice de qualidade de Dickson. Mediante os resultados as mudas se desenvolveram melhor sob profundidade de semeadura de 10 mm e substrato com 100% a.C. Como telas de sombreamento não influenciam no desenvolvimento, recomendando o uso do ambiente a céu aberto. E ainda utilizando o mesmo substrato é indicado lâminas entre 50 e 75% da capacidade de vaso, já para os substratos demais, recomenda-se a lâmina de 25%
Produção de mudas de abobrinha sob estresse salino em diferentes ambientes e substratos
No full textThe interaction between agricultural environment and alternative substrates can attenuate salt stress in zucchini seedlings. Based on that, the objective of this work was to evaluate the production of zucchini seedlings irrigated with saline water and cultivated in different types of environments and substrates. The experimental design was completely randomized, using a split-split plots scheme, with the plot being the three cultivation environments (AM1= full sun; AM2= red screen with 50% shading; AM3= black screen with 50% shading), subplot the three substrates (SB1= biochar + soil; SB2= carbonized rice husk + soil; SB3= cattle manure + soil) and the subplot the two irrigation waters (AI1= 0.8 and AI2= 2.5 dS m-1), with four replications of twenty-five seeds. The variables analyzed were: emergence percentage (EP), emergence speed index (ESI), mean time of emergence (MTE), mean speed of emergence (MSE), stem diameter (SD), seedling height (SH) , root length (RL), shoot dry mass (SDM), root dry mass (RDM) and total dry mass (TDM). The AM3 environment presented better conditions for the variables: EP, ESI and MSE. The environment AM2 presented better conditions for the variable MTE with the use of substrates SB2 and SB3 regardless of the salinity of the irrigation water. The SB3 substrate showed better growth conditions for the variables: SH, SD, SDM and TDM. The SB2 substrate provided better conditions for the variable RDM.A interação entre ambiência agrícola e substratos alternativos pode atenuar o estresse salino em mudas de abobrinha. Com base nisso, o objetivo deste trabalho foi avaliar a produção de mudas de abobrinha irrigadas com águas salinas e cultivadas em diferentes tipos de ambientes e substratos. O delineamento experimental foi o inteiramente casualizado, utilizando esquema de parcelas subsubdivididas, sendo a parcela os três ambientes de cultivo (AM1= pleno sol; AM2= telado vermelho com 50% de sombreamento; AM3= telado preto com 50% de sombreamento), a subparcela os três substratos (SB1= biocarvão + solo; SB2= casca de arroz carbonizado + solo, SB3= esterco bovino + solo) e a subsubparcela as duas águas de irrigação (AI1= 0,8 e AI2= 2,5 dS m-1), com quatro repetições de vinte e cinco sementes. As variáveis analisadas foram: porcentagem de emergência (PE), índice de velocidade de emergência (IVE), tempo médio de emergência (TME), velocidade média de emergência (VME), diâmetro do caule (DC), altura de plântula (AP), comprimento da raiz (CR), massa seca da parte aérea (MSPA), massa seca da raiz (MSR) e massa seca total (MST). O ambiente AM3 apresentou melhores condições para as variáveis: PE, IVE e VME. Já o ambiente AM2 apresentou melhores condições para a variável TME com a utilização dos substratos SB2 e SB3 independente da salinidade da água de irrigação. O substrato SB3 apresentou melhores condições de crescimento para as variáveis: AP, DC, MSPA e MST. O substrato SB2 proporcionou melhores condições para a variável MSR
Photochemical efficiency and growth of sugar apple under irrigation with saline water and foliar nitrogen
Get PDFSalt stress has compromised the worldwide expansion of fruit farming by causing damage to light energy regulation and crop growth, which can be mitigated by applying foliar nitrogen (N). From this perspective, this study aimed to evaluate the chlorophyll contents, fluorescence, and the growth of sugar apple seedlings under irrigation with saline water and foliar N fertilisation. The experiment was conducted in a plant nursery and following a randomized block design referring to five electrical conductivity levels of irrigation water (0.5, 1.15, 2.75, 4.35, and 5.0 dS m-1) and five foliar N levels (0.0, 0.33, 1.15, 1.97, and 2.3 g L-1), with four replications and two plants per plot, totaling nine combinations generated by the Box central composite design. Irrigation water salinity reduces the growth of sugar apple seedlings irrigated with conductivity levels over 1.7 dS m-1 at 90 days after emergence. Foliar N fertilisation increased the photochemical efficiency and growth of sugar apple seedlings. The foliar application of 1.93 g L-1 mitigate the deleterious effects of water salinity on the photochemical efficiency and growth of sugar apple seedlings
umas Gas exchange and leaf area requirement in tall ‘Prata’ banana
No full textThe objective of this study was to evaluate the gas exchange and leaf area requirement for yield of six tall ‘Prata’ banana genotypes, under semi-arid conditions. The genotypes ‘Pacovan’ (AAB), ‘Pacovan Ken’ (AAAB), ‘Preciosa’ (AAAB), ‘Japira’ (AAAB), ‘PV79-34’ (AAAB) and ‘Garantida’ (AAAB) (four tetraploid hybrids and one triploid cultivar) were evaluated in two cycles, arranged in a completely randomized design in a factorial scheme, with five replicates and four usable plants per plot. For the physiological characteristics, a 6 x 12 x 2 factorial arrangement was adopted, with six genotypes, 12 evaluation periods and two reading times in each period, arranged in a completely randomized design. Of the 12 phytotechnical characteristics measured, seven were influenced by the interaction between the factors cultivar and cycle. Internal CO2 concentration, net photosynthesis rate, instantaneous water use efficiency, carboxylation efficiency and quantum efficiency of photosynthesis recorded in banana leaves are higher in the morning, favored by higher stomatal conductance and lower leaf temperature resulting from the meteorological conditions, while transpiration and intrinsic water use efficiency increase in the afternoon. The hybrid ‘PV79-34’ has higher yield and production efficiency per unit of leaf area, associated with high transpiration, compared to the tall ‘Prata’ banana cultivars
Descrição da cinética de desidratação osmótica de fatias circulares de banana com casca
No full textThe kinetics of dehydration and a process commonly used without processing fruit in concentrated sucrose solutions under different temperatures. The aim of the present work was to study the osmotic dehydration kinetics of Pacovan banana slices with bark, 5 mm thick, submitted to temperatures of 40 and 70 ° C, with sucrose solution at concentrations of 40, 50 and 60 ° Brix. Accompanied in the period of 4 hours and as equilibrium conditions, the 24 hours of immersion were used. The loss of water and sucrose gas during the osmotic dehydration of the Lewis, Henderson and Pabis, Page, Peleg and Silva et alii models, through the LAB Fit program to describe the process and the best statistical indicators with effects obtained Peleg models and Silva et alii, to describe the phenomenon of water transfer, already the Page and Peleg models satisfactorily describe the sucrose gain. A graphical inspection of the amount of water (and sucrose) induced by an approximately 80% removal of contained water with no available product up to 800 min. An analysis of the response surfaces obtained in 800 min revealed that treatment at 70 ° C and 60 ° Brix was responsible for increased water loss and sucrose gain.A cinética de desidratação osmótica é uma técnica comumente utilizado no processamento de frutas imersas em soluções de sacarose concentradas sob diferentes temperaturas. O presente trabalho teve como objetivo estudar a cinética de desidratação osmótica de fatias circulares de banana Pacovan com casca, a 5 mm de espessura, submetidas às temperaturas de 40 e 70 °C, com solução de sacarose nas concentrações de 40, 50 e 60 °Brix. Acompanhadas no período de 4 horas e as condições de equilíbrio foram determinadas após 24 horas de imersão. A perda de água e ganho de sacarose durante a desidratação osmótica foram ajustados aos modelos de Lewis, Henderson e Pabis, Page, Peleg e Silva et alii, através do programa LAB Fit para descrever o processo, e os melhores indicadores estatísticos foram obtidos com os modelos de Peleg e Silva et alii, para descrever o fenômeno de transferência de água, já os modelos de Page e Peleg descrevem satisfatoriamente o ganho de sacarose. A inspeção gráfica da quantidade de água (e de sacarose) indicou que a remoção de aproximadamente 80% de água contida no produto ocorreu em até 800 min. A análise das superfícies de resposta obtidas em 800 min revelou que o tratamento a 70 °C e 60 °Brix foi o responsável pela maior perda de água e ganho de sacarose