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Growth of pecan rootstocks with the use of liquid humus in an organic production system
Get PDFPecan farming is a long-term investment which needs quality seedlings to establish an orchard. Pecan rootstocksmust have a vigorous radicular system to form quality seedlings. Liquid humus, which acts as an agent thatpromotes their growth and development, is a bioinput that is specially used in organic production systems.This study aimed at evaluating effects of different frequencies of liquid humus application on pecan rootstockgrowth and development in an organic system. Liquid humus at 30% was applied every 7, 14, 21 and 28 days.The control treatment consisted of water application. The experiment was carried out with ‘Barton’ rootstocksin a greenhouse at the Embrapa Clima Temperado located in Pelotas, RS, Brazil. The following variables wereevaluated 280 and 480 days after transplantation: plant height; stem diameter; leaf area; fresh and dry massesof the aerial part; main and secondary root lengths; fresh and dry masses of roots; fresh and dry masses of themain root; fresh and dry masses of secondary roots; and the Dickson Quality Index. Liquid humus increasedsecondary root length of pecan rootstocks, mainly when it was applied every seven days. Thus, the bioinputmay be used for this purpose.O cultivo da nogueira-pecã é um investimento a longo prazo, necessitando de mudas de qualidade para iniciar o pomar. É necessário que os porta-enxertos de nogueira-pecã possuam sistema radicular vigoroso para formação de uma muda de qualidade. O húmus líquido atua como agente promotor de crescimento e desenvolvimento das mudas, um bioinsumo para uso especialmente em sistema de produção orgânico. O objetivo foi avaliar a frequência de aplicações de húmus líquido no crescimento e desenvolvimento de porta-enxertos de nogueira-pecã em sistema orgânico. Foram testadas frequência a cada 7, 14, 21 e 28 dias de húmus líquido a 30%, além do tratamento controle com a aplicação de água. O experimento foi conduzido com o porta-enxerto da cultivar Barton em casa de vegetação na área experimental da Embrapa Clima Temperado. Avaliou-se após 280 e 480 dias do transplante: altura de planta, diâmetro de tronco, área foliar, massa fresca e seca da parte aérea, comprimento da raiz principal e da raiz secundária; matéria fresca e seca de raiz; massa fresca e seca da raiz principal e massa fresca, seca das raízes secundárias e o Índice de qualidade de mudas de Dickson. O húmus líquido promoveu maior comprimento de raízes secundárias de porta-enxertos de nogueira-pecã, com destaque para a frequência de 7 dias podendo ser utilizado para essa finalidade
Fertigation with nitrogen and humic substances on soil chemical attributes cultivated with west Indian cherry
Get PDFThe use of humic substances (HS) in the soil can increase the efficiency of nitrogen fertilizers and contribute to the increment in soil organic matter and plant nutrient availability. Hence, this study aimed to evaluate, in two production cycles, the effect of applying HS and different nitrogen (N) doses on the chemical attributes and organic matter fractions of a soil cultivated with West Indian cherry in the Brazilian semiarid region. The experiment was set up in split plots, arranged in strips with four replicates. The absence or presence of HS using KS100 as the source was tested in the plots, and N fertilization (50; 75; 100; 125 and 150% of the recommended dose), using urea, was tested in the subplots. Soil pH, H+Al, Al3+, and Na+, K+, P, Ca2+, Mg2+, Fe2+, Mn2+ and Zn2+ contents were determined, and cation exchange capacity and bases saturation (V %) in the 0-0.2 and 0.2-0.4 m layers were calculated. Analyses of stocks of total organic carbon and carbon (C) of the humic acid, fulvic acid and humin fractions, and humic substances were performed. It was possible to observe that, in the second production cycle of West Indian cherry, the soils showed higher contents of nutrients available to plants. Increase in N availability did not enable a clear trend in the behavior of chemical attributes and organic C stocks in the soil. Under the studied conditions, KS100 application allowed a reduction in the C stocks of the HS of the soil
Physiological responses of Physalis angulata L. grown under molybdenum rates in hydroponic system
Get PDFStudies on plant development evaluating the effects of molybdenum (Mo) applications are important for nutritional management in crops, such as Physalis angulata L. crops. Therefore, the objective of this work was to evaluate the responses of Physalis angulata grown under molybdenum rates in hydroponic system. The experiment was conducted in a completely randomized design, with 12 replications and five treatments (Mo rates: 0, 0.005, 0.01, 0.015, and 0.02 mg dm-3 of H2MoO*4H2O). Chlorophyll content, gas exchange parameters, nitrate reductase activity, total protein content, dry weights of leaves, stems, and roots, and root to shoot ratio were evaluated. Supplying Mo (0.02 mg dm-3) provided gains in biomass, which is connected to the total plant weight and total chlorophyll content. The nitrate reductase activity in leaves and roots was stimulated by Mo supplementation; the highest activity was found in the roots. Photosynthetic rate (0.010 mg dm-3) and water use efficiency (0.015 mg dm-3) were favored by increases in Mo rates. The results showed that application of molybdenum as a fertilizer resulted in positive effects on biomass gain, chlorophyll content, photosynthetic rate, and water use efficiency for P. angulata plants grown in hydroponics.Studies on plant development evaluating the effects of molybdenum (Mo) applications are important for nutritional management in crops, such as Physalis angulata L. crops. Therefore, the objective of this work was to evaluate the responses of Physalis angulata grown under molybdenum rates in hydroponic system. The experiment was conducted in a completely randomized design, with 12 replications and five treatments (Mo rates: 0, 0.005, 0.01, 0.015, and 0.02 mg dm-3 of H2MoO*4H2O). Chlorophyll content, gas exchange parameters, nitrate reductase activity, total protein content, dry weights of leaves, stems, and roots, and root to shoot ratio were evaluated. Supplying Mo (0.02 mg dm-3) provided gains in biomass, which is connected to the total plant weight and total chlorophyll content. The nitrate reductase activity in leaves and roots was stimulated by Mo supplementation; the highest activity was found in the roots. Photosynthetic rate (0.010 mg dm-3) and water use efficiency (0.015 mg dm-3) were favored by increases in Mo rates. The results showed that application of molybdenum as a fertilizer resulted in positive effects on biomass gain, chlorophyll content, photosynthetic rate, and water use efficiency for P. angulata plants grown in hydroponics
The effects of plant biostimulants and plant growth regulator applications on plant growth in lilium \u27Adelante\u27
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This experiment was designed, it was determined the effects of mycorrhiza, vermicompost, promalin applications on development of plant properties in a bulbous plant, Lilyum \u27Adelante. Flower branch length (cm), flower branch diameter (mm), internode number, flower bud number, flower bud length (cm), flower stem length (cm), flower width (cm), flower length (cm), number of leaves and leaf length (cm) were measured. The results showed that no treatment increased plant height more than control plants, but each application had different effects on other plant characteristics. As a matter of fact, mycorrhiza increased internode number, flower bud number, flower bud length, flower stem length, flower length, number of leaves and leaf length by 6.3%, 15.6%, 14.2%, 6%, 40%, 10.3%, 2.9% and 6%, respectively. Vermicompost increased flower bud length, flower length and leaf length by 6.6, 12, 15.3% and 16.1%, respectively. Promalin, on the other hand, increased the flower stem length, flower length and leaf length by 56.3% and 15.4%, respectively. The application of mycorrhiza together with Promalin did not have a different effect than the application of Promalin alone, and even showed a lower effect than the application of Promalin alone. Mycorrhiza, on the other hand, was the application that showed the best effect compared to other applications. Therefore, it can be recommended for plant growth in lilies. However, due to the effect of application time and dose on flowering time, it is possible to obtain different results in plant development in lilies.
This experiment was designed, it was determined the effects of mycorrhiza, vermicompost, promalin applications on development of plant properties in a bulbous plant, Lilyum \u27Adelante. Flower branch length (cm), flower branch diameter (mm), internode number, flower bud number, flower bud length (cm), flower stem length (cm), flower width (cm), flower length (cm), number of leaves and leaf length (cm) were measured. The results showed that no treatment increased plant height more than control plants, but each application had different effects on other plant characteristics. As a matter of fact, mycorrhiza increased internode number, flower bud number, flower bud length, flower stem length, flower length, number of leaves and leaf length by 6.3%, 15.6%, 14.2%, 6%, 40%, 10.3%, 2.9% and 6%, respectively. Vermicompost increased flower bud length, flower length and leaf length by 6.6, 12, 15.3% and 16.1%, respectively. Promalin, on the other hand, increased the flower stem length, flower length and leaf length by 56.3% and 15.4%, respectively. The application of mycorrhiza together with Promalin did not have a different effect than the application of Promalin alone, and even showed a lower effect than the application of Promalin alone. Mycorrhiza, on the other hand, was the application that showed the best effect compared to other applications. Therefore, it can be recommended for plant growth in lilies. However, due to the effect of application time and dose on flowering time, it is possible to obtain different results in plant development in lilies
Selection of Prunus clonal rootstocks based on nutritional efficiency state
Get PDFRootstock contributes to increase the absorption and nutrients translocation efficiency. We aimed to select rootstocks according to the nutritional physiological state of the scion cultivar. The experiment was carried out during three periods of leaf collect on the 4-year old peach cv. BRS Libra budded onto 21 rootstocks cultivated in a high density orchard. The following traits were evaluated: xylem water potential, dry leaf mass and chemical leaf nutritional analysis. The collected data were submitted to analysis of variance by the F test and some genetic parameters were estimated. When significant, the means were compared using the Scott-Knott test, at 5% significance. The principal component analysis was performed to verify the interrelationships between the rootstocks and the evaluated traits. The deviation from optimum percentage index was used to select the most nutritional stable rootstock. We observed that rootstock affects the dynamic absorption nutrient parameters in interactions with the scion. The highest foliar levels of P were found in the BRS Libra cultivar when budded onto the rootstocks ʹSanta Rosaʹ, ʹBarrierʹ, ʹTsukuba-1ʹ and ʹRosaflorʹ. The leaf analysis revealed a high variation in the mineral nutritional status among the studied Prunus rootstocks. Most of the mineral macro-elements varied between medium and optimal levels. The rootstocks ʹRigitanoʹ and ʹNemaredʹ showed less nutritional limitation and is recommended for cultivations in high density orchards.Rootstock contributes to increase the absorption and nutrients translocation efficiency. We aimed to select rootstocks according to the nutritional physiological state of the scion cultivar. The experiment was carried out during three periods of leaf collect on the 4-year old peach cv. BRS Libra budded onto 21 rootstocks cultivated in a high density orchard. The following traits were evaluated: xylem water potential, dry leaf mass and chemical leaf nutritional analysis. The collected data were submitted to analysis of variance by the F test and some genetic parameters were estimated. When significant, the means were compared using the Scott-Knott test, at 5% significance. The principal component analysis was performed to verify the interrelationships between the rootstocks and the evaluated traits. The deviation from optimum percentage index was used to select the most nutritional stable rootstock. We observed that rootstock affects the dynamic absorption nutrient parameters in interactions with the scion. The highest foliar levels of P were found in the BRS Libra cultivar when budded onto the rootstocks ʹSanta Rosaʹ, ʹBarrierʹ, ʹTsukuba-1ʹ and ʹRosaflorʹ. The leaf analysis revealed a high variation in the mineral nutritional status among the studied Prunus rootstocks. Most of the mineral macro-elements varied between medium and optimal levels. The rootstocks ʹRigitanoʹ and ʹNemaredʹ showed less nutritional limitation and is recommended for cultivations in high density orchards
Eficiência da utilização de água e energia na produção de tomate em diferentes condições hídricas
No full textThe efficient use of water and energy is fundamental to a sustainable agricultural practice. Deficit irrigationscan contribute to saving water and energetic resources. This work aimed at analyzing the influence of waterreposition in the water and energy efficiency use for growing tomato cocktail type tomato. The experiment wasconducted in vegetation house, and the randomized design was adopted with five levels of water reposition(25, 50, 75, 100 and 125% of evapotranspiration in culture (ETc)) and six repetitions. The morphological contentswere evaluated (number of bunches, number of abortions, fresh mass of aerial part, stem diameter and height),SPAD index (Soil Plant Analysis Development), water demand, productivity, energy use and energy productivity.Data were analyzed through variance analysis, average comparison, regression analysis and correlation. Waterdeficit affects growth, development and productivity of cocktail type tomato. The morphological developmentand the production yield show high correlation with water availability. The water replacement of 75% of ETc hasshown better efficiency in water and electricity use in growing cocktail type tomato.A utilização eficiente da água e da energia é primordial para uma prática agrícola sustentável. Irrigações deficitárias podem contribuir para economia dos recursos hídricos e energéticos. O objetivo do trabalho foi analisar o efeito da reposição hídrica na eficiência da utilização da água e da energia no cultivo de tomate tipo coquetel. O experimento foi conduzido em casa de vegetação, sendo adotado delineamento casualizado com cinco níveis de reposição hídrica (25, 50, 75, 100 e 125% da evapotranspiração da cultura (ETc)) e seis repetições. Foram avaliados componentes morfológicos (número de cachos, número de abortos, massa fresca da parte aérea, diâmetro do caule e altura), índice SPAD (Soil Plant Analysis Development), demanda hídrica, produtividade, uso de energia e produtividade energética. Os dados foram analisados por análise de variância, comparação de médias, análise de regressão e correlação. O desenvolvimento morfológico e o rendimento produtivo apresentaram elevada correlação com a disponibilidade hídrica. O déficit hídrico afetou o crescimento, desenvolvimento e a produtividade do tomate. A lâmina de 75% da ETc demonstrou melhor eficiência da utilização da água e de energia
Cultivo e caracterização físico-química de vinagreira (Hibiscus sabdariffa) sob doses de composto orgânico
No full textAmplamente cultivada em diversos países, a vinagreira (Hibiscus sabdariffa) é utilizada para fins culinários, medicinais e ornamentais. Devido à crescente procura por alimentos mais nutritivos e livre de substâncias tóxicas, visando o desenvolvimento de alternativas ambientalmente corretas, o objetivo desta pesquisa baseia-se no cultivo sustentável de vinagreira sob doses de composto orgânico, verificando o desenvolvimento vegetativo, produtivo e os teores nutritivos da cultura. O experimento foi conduzido na Unidade de Horticultura da Universidade Federal do Acre, consistindo na aplicação de quatro doses de composto orgânico, correspondentes aos tratamentos: T1 - 0 (controle), T2 - 200 mL, T3 - 400 mL e T4 - 600 mL, depositadas nas covas de plantio, espaçadas 0,5 m entre si em três linhas de plantio, com aproximadamente 10 m de comprimento, sendo estas distanciadas a 1 m. O delineamento estatístico foi o de blocos casualizados, contendo cinco blocos. Os dados foram submetidos a análise de regressão à 5% de probabilidade. Foram avaliados parâmetros de crescimento, produção e testes físico-químico das folhas. Resultados significativos foram verificados para altura das plantas e número de ramos de vinagreira, sendo as doses 325 mL e 142 mL, consideradas as melhores para proporcionar maior altura (276 cm) e número de ramos (14), respectivamente. Não houve significância entre as dosagens e os parâmetros de produção e análises físico-química das folhas. A aplicação de composto orgânico promove o crescimento em altura e número de ramos de Hibiscus sabdariffa
Combined fertilization with nitrogen-potassium to mitigate salt stress in okra
Get PDFOkra (Abelmoschus esculentus) is sensitive to the salinity of water and soil, a common abiotic stress in the semi-arid region of northeastern Brazil; however, such sensitivity is variable with water management in the soil-plant-atmosphere system. Thus, the objective was to evaluate the fertilization with nitrogen-potassium combinations in okra cultivated under salt stress. Photosynthetic pigments, gas exchange, growth and fruit quality were evaluated. Fertilization with N1:K1 (40% N + 40% K2O) reduced the damage caused by salt stress and increased the chlorophyll contents, while the application of N4:K4 (130% N + 100% K2O) decreased the damage caused by salt stress and increased the carotenoid contents. The combination of N:K fertilization did not affect gas exchange, however, salt stress decreased these variables. Fertilization with N2:K2 (70% N + 60% K2O) reduced the damage caused by salt stress and increased the leaf area of okra. In addition, salt stress decreased the number of fruits and increased the fresh mass of okra fruits. The N:K fertilization also reduced the damage caused by salt stress and in the soluble solids content, titratable acidity, SS/TA ratio, and ascorbic acid content. Thus, N:K fertilization can be seen as an important agronomic strategy to improve the performance of okra quality subjected to saline conditions.Okra (Abelmoschus esculentus) is sensitive to the salinity of water and soil, a common abiotic stress in the semi-arid region of northeastern Brazil; however, such sensitivity is variable with water management in the soil-plant-atmosphere system. Thus, the objective was to evaluate the fertilization with nitrogen-potassium combinations in okra cultivated under salt stress. Photosynthetic pigments, gas exchange, growth and fruit quality were evaluated. Fertilization with N1:K1 (40% N + 40% K2O) reduced the damage caused by salt stress and increased the chlorophyll contents, while the application of N4:K4 (130% N + 100% K2O) decreased the damage caused by salt stress and increased the carotenoid contents. The combination of N:K fertilization did not affect gas exchange, however, salt stress decreased these variables. Fertilization with N2:K2 (70% N + 60% K2O) reduced the damage caused by salt stress and increased the leaf area of okra. In addition, salt stress decreased the number of fruits and increased the fresh mass of okra fruits. The N:K fertilization also reduced the damage caused by salt stress and in the soluble solids content, titratable acidity, SS/TA ratio, and ascorbic acid content. Thus, N:K fertilization can be seen as an important agronomic strategy to improve the performance of okra quality subjected to saline conditions
Gas exchange in umbu tree accessions
Get PDFThe objective of this work was to evaluate gas exchanges in umbu tree accessions. A 5 × 7 × 2 split-split plot experiment was carried out in a completely randomized design (five accessions – BRS-68, EPAMIG-05, BGU-61, BGU-75, and BGU-50 × seven evaluation dates × two reading times – 8 a.m. and 2 p.m.) with three repetitions. The lower leaf temperatures recorded in BRS-68 and EPAMIG 05 accessions favor higher net photosynthetic rates, water use efficiency and instantaneous carboxylation efficiency compared to BGU 61 accession. Umbu tree regulates transpiration by reducing stomatal conductance under high vapor pressure deficit, although the tree increases transpiration as a defense strategy against heat stress, even with a reduction in stomatal conductance. High temperatures limit instantaneous carboxylation efficiency, photosynthetic rate, and the ratio of photosynthesis to radiation incident on the leaf. Transpiration varies directly with stomatal conductance, while intrinsic water use efficiency varies inversely with internal CO2 concentration.The objective of this work was to evaluate gas exchanges in umbu tree accessions. A 5 × 7 × 2 split-split plot experiment was carried out in a completely randomized design (five accessions – BRS-68, EPAMIG-05, BGU-61, BGU-75, and BGU-50 × seven evaluation dates × two reading times – 8 a.m. and 2 p.m.) with three repetitions. The lower leaf temperatures recorded in BRS-68 and EPAMIG 05 accessions favor higher net photosynthetic rates, water use efficiency and instantaneous carboxylation efficiency compared to BGU 61 accession. Umbu tree regulates transpiration by reducing stomatal conductance under high vapor pressure deficit, although the tree increases transpiration as a defense strategy against heat stress, even with a reduction in stomatal conductance. High temperatures limit instantaneous carboxylation efficiency, photosynthetic rate, and the ratio of photosynthesis to radiation incident on the leaf. Transpiration varies directly with stomatal conductance, while intrinsic water use efficiency varies inversely with internal CO2 concentration
Yield of Syn-1 synthetic varieties of tropical onion resulting from openpollinated Brazilian populations
Get PDFDue to technological limitations for the development of onion hybrids, first-cycle synthetic varieties (Syn1-SV) could be an alternative to partially explore heterotic vigor. The growing areas of onion hybrids in Brazilare mainly defined by bulb yield and uniformity. From this perspective, the present study aimed to developtropical onion Syn1-SV and estimate mid-parent heterosis (Hm), heterobeltiosis (Hp), and standard heterosis(Hs) as an alternative to hybrid development. Six Syn1-SVs, eight open-pollinated (OP) populations, and onecommercial hybrid were evaluated in a randomized block design with three replications, in two semesters, forthe commercial bulb yield (CBY) and days to bulb harvest (DBH). Significant differences were observed fortreatments (T), semesters (S) and the T*S interaction for both variables (p-value<0.05). The OPs ‘Alfa SF RT’ inthe first semester and ‘IPA11’ in the second semester were the most precocious treatments. The highest CBYwas estimated in the commercial hybrid (105.8 t ha-1) and in ‘Alfa SF RT’ (45.5 t ha-1) in the first and secondsemesters, respectively. Three Syn1-SVs showed positive Hm values, ranging from 2.0% to 6.3% for CBY. ThreeSyn1-SV showed positive Hp values in the first semester, ranging from 3.0% to 5.2%, for CBY. Only the Syn1-SV ‘AlfaSF RT’ × ‘BRS Alfa São Francisco’ (48.9 t ha-1) showed positive Hs values, surpassing by a small value the controlOP population ‘IPA11’ (48.0 t ha-1), indicating the potential of Syn1-SV as an option for onion hybrids.Due to technological limitations for the development of onion hybrids, first-cycle synthetic varieties (Syn1-SV) could be an alternative to partially explore heterotic vigor. The growing areas of onion hybrids in Brazilare mainly defined by bulb yield and uniformity. From this perspective, the present study aimed to developtropical onion Syn1-SV and estimate mid-parent heterosis (Hm), heterobeltiosis (Hp), and standard heterosis(Hs) as an alternative to hybrid development. Six Syn1-SVs, eight open-pollinated (OP) populations, and onecommercial hybrid were evaluated in a randomized block design with three replications, in two semesters, forthe commercial bulb yield (CBY) and days to bulb harvest (DBH). Significant differences were observed fortreatments (T), semesters (S) and the T*S interaction for both variables (p-value<0.05). The OPs ‘Alfa SF RT’ inthe first semester and ‘IPA11’ in the second semester were the most precocious treatments. The highest CBYwas estimated in the commercial hybrid (105.8 t ha-1) and in ‘Alfa SF RT’ (45.5 t ha-1) in the first and secondsemesters, respectively. Three Syn1-SVs showed positive Hm values, ranging from 2.0% to 6.3% for CBY. ThreeSyn1-SV showed positive Hp values in the first semester, ranging from 3.0% to 5.2%, for CBY. Only the Syn1-SV ‘AlfaSF RT’ × ‘BRS Alfa São Francisco’ (48.9 t ha-1) showed positive Hs values, surpassing by a small value the controlOP population ‘IPA11’ (48.0 t ha-1), indicating the potential of Syn1-SV as an option for onion hybrids