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Macro and micronutrient accumulation in watermelon
Get PDFThe expansion of crop productivity such as watermelon can be reached by providing adequate nutrition in quantity and when plants need it most. It is known that well-nourished plants better resist biotic and abiotic stresses, being determinants for more sustainable management. In this sense, the objective of the present study was to evaluate the plant growth, the rate of nutrient absorption, the proportion of absorption, and estimate the quantity of exported nutrients by watermelon fruits. The experiment was implemented in randomized block design with eight treatments (phenological phases) - 33 and 40 (growth), 47 and 54 (flowering), 61 and 68 (filling), 75 and 82 (maturation) days after planting (DAP). Each evaluation consisted of plant collection for dry mass, macro, and micronutrient analysis in the shoot (leaves and stems), fruits, and the entire plant. The period between 61 and 68 DAP was the one with the highest plant dry matter increment. The accumulation of macronutrients in the plant shoot showed the following decreasing order: Ca>N>K>Mg>P>S, in the fruits: K>N>P>Ca>Mg>S and in the whole plant: K>N>Ca>P>Mg>S. For micronutrients, the decreasing order of accumulation for the shoot and the entire plant were Fe>Mn>Zn>B>Cu, and for fruits were Fe>B>Zn>Mn>Cu.The expansion of crop productivity such as watermelon can be reached by providing adequate nutrition in quantity and when plants need it most. It is known that well-nourished plants better resist biotic and abiotic stresses, being determinants for more sustainable management. In this sense, the objective of the present study was to evaluate the plant growth, the rate of nutrient absorption, the proportion of absorption, and estimate the quantity of exported nutrients by watermelon fruits. The experiment was implemented in randomized block design with eight treatments (phenological phases) - 33 and 40 (growth), 47 and 54 (flowering), 61 and 68 (filling), 75 and 82 (maturation) days after planting (DAP). Each evaluation consisted of plant collection for dry mass, macro, and micronutrient analysis in the shoot (leaves and stems), fruits, and the entire plant. The period between 61 and 68 DAP was the one with the highest plant dry matter increment. The accumulation of macronutrients in the plant shoot showed the following decreasing order: Ca>N>K>Mg>P>S, in the fruits: K>N>P>Ca>Mg>S and in the whole plant: K>N>Ca>P>Mg>S. For micronutrients, the decreasing order of accumulation for the shoot and the entire plant were Fe>Mn>Zn>B>Cu, and for fruits were Fe>B>Zn>Mn>Cu.The expansion of crop productivity such as watermelon can be reached by providing adequate nutrition in quantity and when plants need it most. It is known that well-nourished plants better resist biotic and abiotic stresses, being determinants for more sustainable management. In this sense, the objective of the present study was to evaluate the plant growth, the rate of nutrient absorption, the proportion of absorption, and estimate the quantity of exported nutrients by watermelon fruits. The experiment was implemented in randomized block design with eight treatments (phenological phases) - 33 and 40 (growth), 47 and 54 (flowering), 61 and 68 (filling), 75 and 82 (maturation) days after planting (DAP). Each evaluation consisted of plant collection for dry mass, macro, and micronutrient analysis in the shoot (leaves and stems), fruits, and the entire plant. The period between 61 and 68 DAP was the one with the highest plant dry matter increment. The accumulation of macronutrients in the plant shoot showed the following decreasing order: Ca>N>K>Mg>P>S, in the fruits: K>N>P>Ca>Mg>S and in the whole plant: K>N>Ca>P>Mg>S. For micronutrients, the decreasing order of accumulation for the shoot and the entire plant were Fe>Mn>Zn>B>Cu, and for fruits were Fe>B>Zn>Mn>Cu
Estabilidade e adaptabilidade de cultivares de alface em diferentes substratos
No full textLettuce is a leafy species cultivated in different regions of the world. During the seedling production process, the choice of the substrate is one of the most important steps. Considering diversity of type and price, it is common to produce alternative substrates using inputs with potential to cause environmental impacts. Sludge is a waste from water treatment plants, which has agricultural potential. This research aimed to estimate the stability and adaptability of five lettuce cultivars under different substrate compositions in the early stages of growth and yield. Two experiments were carried out in 2021: 1) in greenhouse, in which five cultivars (‘Veneranda’, ‘Camila’, ‘Elba’, ‘Vitória Verdinha’, ‘Diva’), three substrates (‘Vida Verde’, Bioplant 434, Bioplant 401) and three sludge doses (0, 20, 40%) were tested on the seedling quality index (SQI); 2) at field level, the yield of seedlings produced in the 1st stage was evaluated. From a double-entry table (matrix M), consisting of five cultivars and nine environments (combination of 3 substrates x 3 sludge doses), deviance analysis, WAASB and ASV stability indexes, biplots of the AMMI method and BLUPs were applied. Significant GE interaction identified cultivars adapted to specific substrates. ‘Camila’ cultivar was stable in terms of SQI and yield; ‘Diva’ was the most unstable, but with specific adaptation to five substrate for SQI and three for yield. The addition of 40% of sludge reduced the SQI; however, it did not influence the yield when associated with ‘Vida Verde’ and Bioplant 434, being indicated for production of lettuce.A alface é uma espécie folhosa cultivada em diversas regiões do mundo. Durante o processo de produção de mudas, a escolha do substrato é uma das etapas mais importantes. Considerando a diversidade de tipos e o preço, é comum a produção de substratos alternativos, utilizando-se insumos com potencial causador de impactos ambientais. O lodo é um resíduo das estações de tratamento de água que apresenta potencial agrícola. Esta pesquisa objetivou estimar a estabilidade e a adaptabilidade de cinco cultivares de alface sob diferentes composições de substratos nos estágios iniciais de crescimento e produtividade. Foram realizados dois experimentos em 2021: 1º) em casa de vegetação, em que foram testados cinco cultivares (Veneranda, Camila, Elba, Vitória Verdinha, Diva), três substratos (Vida Verde, Bioplant 434, Bioplant 401) e três doses de lodo (0, 20, 40%), sobre o índice de qualidade da muda (IQM); 2º) em nível de campo, avaliou-se a produtividade das mudas produzidas na 1ª etapa. A partir de uma tabela de dupla entra, constituída de cinco cultivares e nove ambientes (combinação de 3 substratos x 3 doses de lodo), aplicou-se a análise de deviance, os índices de estabilidade WAASB e ASV, biplots do método AMMI e BLUPs. Interação GE significativa identificou cultivares adaptados a substratos específicos. O cultivar Camila foi estável quanto ao IQM e produtividade; Diva foi o mais instável, porém com adaptação específica a cinco substratos para o IQM e três para a produtividade. A adição de 40% de lodo reduziu o IQM, porém, não influenciou a produtividade quando associado ao Vida Verde e Bioplant 434, sendo indicado para produção de alface
Relationship between physicochemical characteristics and gene expression in lettuce as a tool for genetic improvement
Get PDFAlface ( Lactuca sativa L.) is a leafy vegetable worldwide consumed. It is found in its constitution vitamins and minerals, as well as bioactive compounds, such as phenolic compounds, flavonoids and anthocyanins. Since anthocyanins are responsible for the red color of the leaves and in the body prevents the appearance of non-communicable chronic diseases by the fight against free radicals. The lettuce for being present in the diet of the population becomes a promising plant for biofortification with the selection of plants with high levels of anthocyanins. The objective of the present work was to study the quantitative distribution of anthocyanin in leaves of lettuce plants of a segregating F2 population obtained from the initial crossing between two color contrasting parents (green and red).. The color, anthocyanin and flavonoid contents, as well as color correlation with anthocyanin content and the heritability of these characteristics. It was concluded that the anthocyanin content in leaves of lettuce is controlled by more than one gene with partial dominance of the genes that confer higher levels. Intense red coloration can be used as an alternative in lettuce breeding programs to identify superior lettuce genotypes with high anthocyanin content. Transgressive segregation as well as the higher heritability values observed in the studied traits will allow selecting in segregating generations, superior genotypes in accordance with the proposed objectives.Alface ( Lactuca sativa L.) is a leafy vegetable worldwide consumed. It is found in its constitution vitamins and minerals, as well as bioactive compounds, such as phenolic compounds, flavonoids and anthocyanins. Since anthocyanins are responsible for the red color of the leaves and in the body prevents the appearance of non-communicable chronic diseases by the fight against free radicals. The lettuce for being present in the diet of the population becomes a promising plant for biofortification with the selection of plants with high levels of anthocyanins. The objective of the present work was to study the quantitative distribution of anthocyanin in leaves of lettuce plants of a segregating F2 population obtained from the initial crossing between two color contrasting parents (green and red).. The color, anthocyanin and flavonoid contents, as well as color correlation with anthocyanin content and the heritability of these characteristics. It was concluded that the anthocyanin content in leaves of lettuce is controlled by more than one gene with partial dominance of the genes that confer higher levels. Intense red coloration can be used as an alternative in lettuce breeding programs to identify superior lettuce genotypes with high anthocyanin content. Transgressive segregation as well as the higher heritability values observed in the studied traits will allow selecting in segregating generations, superior genotypes in accordance with the proposed objectives
Nutrient omission on growth and leaf contents of blackberry
Get PDFCultivation of blackberry has gradually expanded in Brazil, due to their rusticity and low production cost; thus, it stands out as an excellent option for product diversification. There is a need to improve technical information on the management of this crop, especially mineral nutrition. Knowledge of the visual symptoms of nutritional deficiency and foliar contents of the nutrients allows helps farmers to choose the most adequate fertilization for plants. This study aimed at evaluating nutritional aspects and effects of nutrient omission on the growth of BRS Xingu blackberry. Treatments consisted of complete solutions and individual omission of the following nutrients: nitrogen (N), phosphorus (P), potassium (K), calcium (C), magnesium (Mg), boron (B), manganese (Mn), zinc (Zn) and iron (Fe). The following variables were evaluated: leaf dry matter, root dry matter, total dry mass, macro- and micronutrients contents in leaves and visual symptoms of nutrient deficiency. Macronutrient and B deficiencies limit growth of blackberry. B omission led to the highest decrease in plant growth, besides leaf wrinkling, a fact that shows that BRS Xingu is susceptible to its deficiency. Correlation was found between N and Ca, N and P and B and Ca leaf contents. Low leaf contents of N, K, Ca and B were observed when these nutrients were omitted from the solution.  
Production of Acalypha wilkesiana seedlings using stem cuttings
Get PDFThe objective of this work was to evaluate the rooting of cuttings of Acalifa (Acalypha Wilkesiana) with different concentrations of indolbutyric acid (IBA). The matrix plant from which the cuttings were taken, is planted as a hedge and located at the biology institute of the Federal Rural University of Rio de Janeiro in the city of Seropédica-RJ. The experimental design was completely randomized, in a 3x3 factorial, with three different concentrations of IBA (0, 1000 and 2000 mg L-1 or 0, 2000 and 4000 mg L-1 for 15 seconds) and three types of cuttings (herbaceous, semi-woody and woody), with three replications and ten cuttings per plot. The experiments were carried out at two different times, namely: autumn and winter / spring. The following were evaluated: percentage of live cuttings, rooted, with callus and sprouting, number of roots per cut, length of the largest root. Acalypha wilkesiana can be propagated by stem cuttings, whether woody, semi-woody or herbaceous cuttings. However, herbaceous cuttings have a lower percentage of survival and rooting. Also, is a species of easy rooting through cutting of stems, dispensing with the use of AIB. Stems collected in the autumn period yield greater efficiency and productivity in the propagation of cuttings by cuttings.The objective of this work was to evaluate the rooting of cuttings of Acalifa (Acalypha Wilkesiana) with different concentrations of indolbutyric acid (IBA). The matrix plant from which the cuttings were taken, is planted as a hedge and located at the biology institute of the Federal Rural University of Rio de Janeiro in the city of Seropédica-RJ. The experimental design was completely randomized, in a 3x3 factorial, with three different concentrations of IBA (0, 1000 and 2000 mg L-1 or 0, 2000 and 4000 mg L-1 for 15 seconds) and three types of cuttings (herbaceous, semi-woody and woody), with three replications and ten cuttings per plot. The experiments were carried out at two different times, namely: autumn and winter / spring. The following were evaluated: percentage of live cuttings, rooted, with callus and sprouting, number of roots per cut, length of the largest root. Acalypha wilkesiana can be propagated by stem cuttings, whether woody, semi-woody or herbaceous cuttings. However, herbaceous cuttings have a lower percentage of survival and rooting. Also, is a species of easy rooting through cutting of stems, dispensing with the use of AIB. Stems collected in the autumn period yield greater efficiency and productivity in the propagation of cuttings by cuttings
Quando iniciar e com qual frequência se deve realizar a fertirrigação em mudas de repolho?
No full textAlthough cabbage is one of the most important vegetables in Brazil, seedling production is carried out empirically by producers, given that there are no literature reports on the optimal start time and management strategy for seedling fertigation. The present study aimed to assess the influence of fertigation management on the development of cabbage seedlings, in order to determine the best start time and application intervals for nutrient supply. The study consisted of two experiments conducted in a randomized block design, with six repetitions each. The first involved six fertigation start times (0, 3, 6, 9, 12 and 15 days after emergence) and the second consisted of five treatments, that is, five fertigation application frequencies (every 3, 4, 5, 6 and 7 days after the first application). Biometric, physiological and nutrient characteristics were assessed when the seedlings reached the ideal (commercial) transplanting stage. Fertigation start times had a significant effect on the number of leaves, shoot and root dry weight, leaf area and macronutrient accumulation. The best resultswere obtained for a start time of 0 to 6 days after emergence (DAE). Application intervals had a significant effect only on calcium and sulfur accumulation. It was concluded that cabbage seedling fertigation should start three days after emergence, adopting a four-day application interval.Apesar do repolho ser uma das principais hortaliças no Brasil, a produção de mudas desta cultura é feita de forma empírica pelos produtores, visto que não há relatos na literatura de quando iniciar e como manejar a fertirrigação nas mudas. Diante disto, o objetivo do presente estudo foi avaliar a influência do manejo da fertirrigação no desenvolvimento de mudas de repolho, afim de se determinar a melhor época de início do fornecimento e intervalo de aplicação dos nutrientes. O trabalho foi composto por dois experimentos conduzidos em delineamento de blocos casualizados, com seis repetições cada. O primeiro foi composto por seis tratamentos, sendo eles seis épocas de início da fertirrigação (0, 3, 6, 9, 12 e 15 dias após a emergência). O segundo experimento constituiu-se de cinco tratamentos, sendo cinco frequências de aplicação da fertirrigação (a cada 3, 4, 5, 6 e 7 dias após a primeira aplicação). Foram avaliadas características biométricas, fisiológicas e nutricionais das mudas no ponto de transplante. Houve efeito significativo das épocas de início da fertirrigação sobre as variáveis número de folhas, massa seca da parte aérea, massa seca das raízes, área foliar e acúmulo de todos os macronutrientes. Os melhores resultados concentraram-se com início da fertirrigação de 0 a 6 dias após a emergência. Os intervalos de aplicação influenciaram significativamente apenas os acúmulos de Ca e S. Conclui-se que, na produção de mudas de repolho a fertirrigação deve ser iniciada aos três dias após a emergência, adotando-se intervalo de aplicação de quatro dias
Desempenho de mudas de pinha em diferentes doses de adubação fosfatada
No full textAdding phosphorus in the composition of the substrate for the seedlings production contributes to a faster growth of seedlings, increases the resistance to biotic and abiotic stresses, also improves the efficiency in the use of nutrients and water in many vegetal species. The objective of this research was to evaluate the vegetative growth and quality of Annona squamosa L. seedlings, propagated by seeds, regarding the application of single superphosphate in enriched sugarcane bagasse substrate. The completely randomized design consisted of six treatments arranged according to the following application doses (0; 0.75; 1.5; 2.25; 3.0 and 3.75 kg), using the single superphosphate in substrate, with four replicates per treatment. At 120 days after sowing, number of leaves, leaf area, shoot height, stem diameter, shoot dry mass, root dry mass, total dry mass, ratio between shoot dry mass and root dry mass, chlorophyll a, chlorophyll b, total chlorophyll, and Dickson’s Quality Index were evaluated. The maximum growth of the pine cone plants were noted when added single superphosphate to the substrate in doses ranging from 0.6 to 1.2 kg.m-3. The phosphate fertilizer favored the growth especially of the roots and leaf area and improved the quality of pine cone seedlings.A adição de fósforo na composição do substrato para produção de mudas contribui para um crescimento mais rápido das plântulas, aumenta a resistência aos estresses bióticos e abióticos e melhora ainda a eficiência no uso de nutrientes e da água em várias espécies vegetais. O objetivo desta pesquisa foi avaliar o crescimento vegetativo e a qualidade de mudas de Annona squamosa, propagada por sementes, em relação a aplicação de superfosfato simples em substrato de bagaço de cana enriquecido. O delineamento inteiramente casualizado constou de seis tratamentos com as seguintes doses de aplicação ( 0; 0,75; 1,5; 2,25; 3,0 e 3,75 kg), usando o superfosfato simples em substrato, com quatro repetições de 10 plantas por tratamento. Aos 120 dias após semeadura, número de folhas, área foliar, altura da parte aérea, diâmetro do caule, fitomassa seca da parte aérea, fitomassa seca do sistema radicular, fitomassa seca total, relação entre as fitomassas seca da parte aérea e do sistema radicular, clorofila a, clorofila b, clorofila total e o índice de qualidade de Dickson, foram avaliados. O crescimento máximo das plantas de pinha foi observado com a adição de superfosfato simples ao substrato em doses estimadas na faixa de 0,6 a 1,2 kg m-³ de substrato. O fertilizante fosfatado favoreceu o crescimento principalmente de raízes e área foliar e proporcionou melhor qualidade de mudas de pinha
Plant growth and yield of garlic (Allium sativum L.) under applications of liquid biofertilizers
Get PDFGarlic is a highly relevant vegetable crop from the food and medicinal point of view in the culture of different peoples around the world. The new discoveries of the active components present in the bulbs increase the demand and require that garlic’s production system meets the demands of the market in quantity and quality. The nutrition in vegetables is crucial for the production and protection of crops, and in the garlic crop it is usual practice to apply minerals via leaf application during the cycle. The use and benefits of organic sources associated with minerals in the garlic crop raise questions about the viability of the leaf application method in this crop. The objective of this study was to evaluate the effectiveness of biofertilizers containing humic acids applied via leaf application in the crop of garlic (Allium sativum) in relation to the control (absence of humic acid). There was no significant variation for the foliar application of biofertilizers for the development parameters (aerial part, root system and bulb formation) and garlic production classes. Biofertilizer 4 at the dose of 30 L ha-1 stood out compared to the Biofertilizers 2 and 3 for total productivity. The use of foliar biofertilizers with organic components associated with minerals can be considered an interesting alternative for the cultivation of garlic, especially if evaluated in the long term and considering the global benefits to the cultivation system
Physiological and metabolic responses in broccoli plants fertilized with green manure
Get PDFGrasses and legumes affect differently the amount of N in the soil over time, mainly due to the differences in the chemical characteristics of its mass. Changes in the availability of N influence the absorption and assimilation of N, which will influence physiological processes in the plants. The objective of this paper is to evaluate the changes in gas exchange, chlorophyll fluorescence and biochemical activity in leaves of broccoli grown under different green manure amendments. The experiment was designed in a complete randomized block design, using the mass of jack bean (JB) and millet (M) pure and in mixtures and one control, totaling six treatments: Control, 100JB, 75JB25M, 50JB50M, 25JB75M, 100M, with four replicates. The canopy area, N content, gas exchange, and biochemical analyzes were evaluated on the broccoli index leaf 40 days after broccoli transplantation. The higher ratio of jack bean, the higher the canopy area, the N content and the amino acid, protein and malate content, and lower starch content, possibly due to the higher N mineralization in this green manure.Grasses and legumes affect differently the amount of N in the soil over time, mainly due to the differences in the chemical characteristics of its mass. Changes in the availability of N influence the absorption and assimilation of N, which will influence physiological processes in the plants. The objective of this paper is to evaluate the changes in gas exchange, chlorophyll fluorescence and biochemical activity in leaves of broccoli grown under different green manure amendments. The experiment was designed in a complete randomized block design, using the mass of jack bean (JB) and millet (M) pure and in mixtures and one control, totaling six treatments: Control, 100JB, 75JB25M, 50JB50M, 25JB75M, 100M, with four replicates. The canopy area, N content, gas exchange, and biochemical analyzes were evaluated on the broccoli index leaf 40 days after broccoli transplantation. The higher ratio of jack bean, the higher the canopy area, the N content and the amino acid, protein and malate content, and lower starch content, possibly due to the higher N mineralization in this green manure
Chemical thinning of peach trees
Get PDFPeach tree thinning is essential to harvest quality fruits and to keep balanced production for several years. Manual thinning of peach trees demands much work force and increases production costs. Chemical thinning may be an alternative solution, but efficiency depends on doses and species. This study aimed at evaluating the effect of metamitron – applied at different concentrations – on chemical thinning of peach trees in the south of Brazil. The experiment was carried out in a commercial peach tree orchard where ‘Sensação’ cultivars, in Morro Redondo, Rio Grande do Sul (RS) state, Brazil. The following metamitron concentrations were applied at concentrations of 100 mg L-1, 200 mg L-1, 300 mg L-1, 400 mg L-1, manual thinning was carried out 40 days after full bloom (DAFB) and to the treatment where the plants have no thinning. Fruit abscission, effective fructification, total number of plants per plant, production per plant, mean mass and fruit diameter were evaluated. Concentrations of 300 and 400 mg L-1 metamitron 40 DAFB provides promoted high fruit abscission, besides decreasing the number of fruits and production. Therefore, concentrations of 100 and 200 mg L-1 of metamitron 40 DAFB provides results in an efficient thinning practice similar to manual thinning for production, mass and fruit diameter