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Recipientes e doses de adubo de liberação controlada na produção de rabanete em ambiente protegido
No full textRadish cultivation has aroused the interest of agricultural producers, but it is still necessary to improve management practices that allow greater production and quality of tubers. In this sense, the objective of this work was to evaluate the growth and production of radishes grown in containers of different volumes, filled with an environment enriched with increasing doses of controlled authorization fertilizer (LCA), in a greenhouse. The research was carried out in the Didactic Garden of the Federal University of Ceará. The experimental design used was in randomized blocks, in a split-plot scheme, with three replications. The plots were constituted by the volumes of containers (31 and 100 cm3.cell-1) and as subplots by the fertilization rates (0, 4, 8, 12 kg.m-3 or g.L-1). The number of leaves, shoot height, shoot fresh and dry mass, leaf area, chlorophyll \u27a\u27 and \u27b\u27, tuber length and diameter, tuber fresh and dry mass and total production per area were evaluated. . Plants grown in a 100 cm3 container showed higher values for all variables and the controlled metering doses of fertilizer resulted in an increase in radish growth and production. It is concluded that it is possible to grow radish in containers filled with ALC-enriched substrate under screen-type protection conditions.O cultivo do rabanete tem despertado interesse por parte dos produtores agrícolas, porém ainda é preciso o desenvolvimento e aprimoramento de práticas de manejo que possibilitem maior produção e qualidade das túberas. esse sentido, objetivou-se com este trabalho avaliar o crescimento e a produção de rabanetes cultivados em recipientes de diferentes volumes, preenchidos com substrato enriquecido com doses crescentes de adubo de liberação controlada (ALC), em ambiente protegido do tipo telado. A pesquisa foi realizada na Horta Didática da Universidade Federal do Ceará. O delineamento experimental utilizado foi em blocos ao acaso, em esquema de parcela subdividida, com três repetições. As parcelas foram constituídas pelos volumes de recipientes (31 e 100 cm3.célula-1) e as subparcelas pelas doses de adubação (0, 4, 8, 12 kg.m-3 ou g.L-1). Avaliaram-se o número de folhas, altura da parte aérea, massa fresca e seca da parte aérea, área foliar, clorofila ‘a’ e ‘b’, comprimento e diâmetro da túbera, massa fresca e seca da túbera e produção total por área. As plantas cultivadas em recipiente de 100 cm3 apresentaram os maiores valores para todas as variáveis e as doses de adubo de liberação controlada crescentes resultaram em incremento no crescimento e produção do rabanete. Conclui-se que é possível produzir rabanete em recipientes preenchidos com substrato enriquecido com adubo ALC em condições de cultivo protegido do tipo telado
Defence-related components in cucumber susceptibility to target spot
Get PDFTarget spot is an important disease in cucumber culture. Due to differences in the susceptibility of cucumber cultivars to the disease, the objective was to evaluate the behavior of three cvs. in terms of leaf trichome density and biochemical variables in the interaction with the pathogen Corynespora cassiicola. The density of trichomes was evaluated on both sides of the leaves. The activity of peroxidase and polyphenol oxidase enzymes and the levels of free and bound phenolic compounds were evaluated one, three and five days after inoculation or not with the pathogen. The enzymatic activity was higher in the Safira cv., less susceptible to the disease, in relation to the Taiko and Soldier cvs. Inoculated plants showed higher peroxidase activity, showing that the response to infection was accompanied by the synthesis of this enzyme, and it increased with the days after inoculation. The levels of phenolic compounds varied according to the cvs. and as a function of time, with the highest levels in the Safira and Soldier cvs. Higher density of trichomes was found in the Safira cv., with no differences between Soldier and Taiko cvs. The adaxial side of the leaves had a greater number of trichomes than the abaxial side. No direct relationships were observed between biochemical and trichome variables and disease severity in cucumber cvs., since the Soldier cv., the most susceptible to the disease, did not differ in relation to \u27Taiko\u27 in enzymatic activities, free phenolic compounds and number of trichomes, including higher levels of bound phenolic compounds.A mancha alvo constitui importante doença na cultura do pepino. Em virtude de diferenças na suscetibilidade das cultivares de pepino em relação a doença, objetivou-se avaliar o comportamento de três cvs. quanto a densidade de tricomas foliares e de variáveis bioquímicas na interação com o patógeno Corynespora cassiicola. A densidade de tricomas foi avaliado em ambas os lados das folhas. A atividade das enzimas peroxidase e polifenoloxidade e os teores dos compostos fenólicos livres e ligados foram avaliados após um, três e cinco dias da inoculação ou não do patógeno. A atividade enzimática foi superior na cv. Safira, menos suscetível a doença, em relação às cvs. Taiko e Soldier. As plantas inoculadas apresentaram maior atividade da peroxidase, evidenciando que a resposta à infecção foi acompanhada pela síntese dessa enzima, e foi crescente com os dias após a inoculação. Os teores de compostos fenólicos foram variáveis em função das cvs. e em função do tempo, com os maiores teores nas cvs. Safira e Soldier. Maior densidade de tricomas foi constatado na cultiva Safira, não havendo diferenças entre as cvs. Soldier e Taiko. O lado adaxial das folhas apresentou maior número de tricomas em relação ao abaxial. Não foram observadas relações diretas das variáveis bioquímicas e de tricomas com a severidade da doença nas cvs. de pepino, uma vez que a cv. Soldier, a mais suscetível a doença, não diferiu em relação à ‘Taiko’ nas atividades enzimáticas, compostos fenólicos livres e número de tricomas, apresentando, inclusive, maiores teores de compostos fenólicos ligados
Agrophysiology, biochemical, and yielding characteristics of Chinese cabbage due to formulations and concentrations of nutrient in hydroponic
Get PDFHydroponic solution from agricultural organic waste can be used as an alternative to chemical solutions andstrongly increases the growth and yield of Chinese cabbage plants. This study was to obtain formulations,concentrations, and their interactions that have the potential to increase the agronomic, physiological,biochemical, and yielding characteristics of Chinese cabbage in hydroponic culture. This study was conductedfrom September to November 2022 using a randomized block design with two factors and three replications.The first factor was the formulation of organic nutrient solutions (F1= banana peels+bean sprouts+eggshells; F2=banana humps+onion peels+bean sprouts+moringa leaves; F3= moringa leaves+onion peels+bean sprouts; F4=AB mix as a comparison). The second factor was the concentrations (600; 900; 1,200; 1,500 ppm). Data wereanalyzed using ANOVA and proceeded with the Duncan at P<0.05. The results showed that formulations F3 andF2 significantly increased Mg and chlorophyll b levels while formulation F1 increased nitrate and flavonoids. Theconcentrations ranged from 1,200 to 1,500 ppm showed the highest yield and shoot fresh weight were 2.86 kgm-2 year-1 and 30.70 g. The F3C4 interaction was highly recommended to increase the yield of Chinese cabbageby 2.68 kg m-2 year-1 compared to the other liquid organic fertilizers and it could be used as a substitute for usingliquid chemical fertilizers in hydroponic culture.Hydroponic solution from agricultural organic waste can be used as an alternative to chemical solutions andstrongly increases the growth and yield of Chinese cabbage plants. This study was to obtain formulations,concentrations, and their interactions that have the potential to increase the agronomic, physiological,biochemical, and yielding characteristics of Chinese cabbage in hydroponic culture. This study was conductedfrom September to November 2022 using a randomized block design with two factors and three replications.The first factor was the formulation of organic nutrient solutions (F1= banana peels+bean sprouts+eggshells; F2=banana humps+onion peels+bean sprouts+moringa leaves; F3= moringa leaves+onion peels+bean sprouts; F4=AB mix as a comparison). The second factor was the concentrations (600; 900; 1,200; 1,500 ppm). Data wereanalyzed using ANOVA and proceeded with the Duncan at P<0.05. The results showed that formulations F3 andF2 significantly increased Mg and chlorophyll b levels while formulation F1 increased nitrate and flavonoids. Theconcentrations ranged from 1,200 to 1,500 ppm showed the highest yield and shoot fresh weight were 2.86 kgm-2 year-1 and 30.70 g. The F3C4 interaction was highly recommended to increase the yield of Chinese cabbageby 2.68 kg m-2 year-1 compared to the other liquid organic fertilizers and it could be used as a substitute for usingliquid chemical fertilizers in hydroponic culture
Organic substrates in the development of camu-camuzeiro (Myrciaria dubia (H. B. K.) McVaugh) in the amazon region
Get PDFAmazon is the largest tropical forest on the planet, it has a variety of plant species with emphasis on manyfruit trees, such as the camu-camuzeiro (Myrciaria dubia (H. B. K.) McVaugh), which occurs naturally on thebanks of rivers, lakes, lowlands and flooded forest of the Amazon. The objective of this study is to evaluate thedevelopment of camu-camuzeiro seedlings in different organic substrates. The experiment was conductedin the seedling production nursery of the Federal Rural University of Amazon. The experimental design wasentirely randomized, with ten treatments and five repetitions, each portion was represented by ten plants,totaling 500 seedlings. The substrates evaluated were: T1 - Humus; T2 - Humus + Bird manure; T3 - Humus + Bovinemanure; T4 - Humus + Açaí kernel; T5 - Humus + Chestnut shell; T6 - Humus + Chestnut shell + Poultry manure;T7 - Humus + Bovine manure + Chestnut shell; T8 - Humus + Açaí kernel + Poultry manure; T9 - Humus + Açaíkernel + Bovine manure; T10 - Commercial. The different substrates used influenced the development of camucamuzeiroseedlings evaluated at 180 days. The treatments with a substrate based on Humus (T1), Humus + Açaíkernel (T4), Humus + Chestnut shell (T5), Humus + Chestnut shell + Poultry manure (T6), Humus + Bovine manure +Chestnut shell (T7), Humus + Açaí Kernel + Bovine manure (T9) and the commercial substrate (T10) are the bestfor a satisfactory development of this crop in the production field.Amazon is the largest tropical forest on the planet, it has a variety of plant species with emphasis on manyfruit trees, such as the camu-camuzeiro (Myrciaria dubia (H. B. K.) McVaugh), which occurs naturally on thebanks of rivers, lakes, lowlands and flooded forest of the Amazon. The objective of this study is to evaluate thedevelopment of camu-camuzeiro seedlings in different organic substrates. The experiment was conductedin the seedling production nursery of the Federal Rural University of Amazon. The experimental design wasentirely randomized, with ten treatments and five repetitions, each portion was represented by ten plants,totaling 500 seedlings. The substrates evaluated were: T1 - Humus; T2 - Humus + Bird manure; T3 - Humus + Bovinemanure; T4 - Humus + Açaí kernel; T5 - Humus + Chestnut shell; T6 - Humus + Chestnut shell + Poultry manure;T7 - Humus + Bovine manure + Chestnut shell; T8 - Humus + Açaí kernel + Poultry manure; T9 - Humus + Açaíkernel + Bovine manure; T10 - Commercial. The different substrates used influenced the development of camucamuzeiroseedlings evaluated at 180 days. The treatments with a substrate based on Humus (T1), Humus + Açaíkernel (T4), Humus + Chestnut shell (T5), Humus + Chestnut shell + Poultry manure (T6), Humus + Bovine manure +Chestnut shell (T7), Humus + Açaí Kernel + Bovine manure (T9) and the commercial substrate (T10) are the bestfor a satisfactory development of this crop in the production field
APLICAÇÃO DE ZEÓLITAS COMO ALTERNATIVA PARA MINORAR EFEITOS DO ESTRESSE SALINO EM Ixora coccínea L.
No full textZeolites are crystalline aluminosilicates with cation adsorption capacity in soils and waters. In this context, the objective was to evaluate the potential of a synthetic type A zeolite, applied to the substrate, to reduce the extraction of Na + by plants of the ornamental species Ixora coccínea L., and, consequently, to mitigate the negative effects of salinity on physiology and in the growth of this species. The research was carried out in a greenhouse, from April to June 2018. The experiment was carried out under a randomized block design, in a 4 × 2 factorial scheme, corresponding to four levels of electrical conductivity of the irrigation water - CEa ( 0.6, 2.0, 3.4 and 5.0 dS m-¹), with the presence and absence of zeolite and four repetitions. The salinity of the irrigation water had deleterious effects on the ornamental species I. coccínea, causing reductions in leaf gas exchange, flower production and plant growth. No accumulation of Na + was observed in the leaf tissues, suggesting that the negative effects of salinity were mainly associated with the osmotic component of salt stress. Interaction between salinity and zeolites was observed for the production of aerial and total biomass, however, there was low sodium accumulation in the leaves, which made it impossible to conclude about any beneficial effect of zeolite in I. coccínea under salt stress.Zeólitas são aluminossilicatos cristalinos com capacidade de adsorção de cátions em solos e águas. Nesse contexto, objetivou-se avaliar o potencial de uma zeólita sintética do tipo A, aplicada ao substrato, em reduzir a extração de Na+ por plantas da espécie ornamental Ixora coccínea L., e, consequentemente, mitigar os efeitos negativos da salinidade na fisiologia e no crescimento dessa espécie. A pesquisa foi desenvolvida em casa de vegetação, no período de abril a junho de 2018. O experimento foi realizado sob um delineamento em blocos casualizados, em esquema fatorial 4×2, correspondendo a quatro níveis de condutividade elétrica da água de irrigação - CEa (0,6; 2,0; 3,4 e 5,0 dS m-¹), com presença e ausência de zeólita e quatro repetições. A salinidade da água de irrigação apresentou efeitos deletérios à espécie ornamental I. coccínea, provocando reduções nas trocas gasosas foliares, na produção de flores e no crescimento das plantas. Não se observou acúmulo de Na+ nos tecidos foliares, sugerindo que os efeitos negativos da salinidade foram associados principalmente ao componente osmótico do estresse salino. Interação entre salinidade e zeólitas foi observada para produção de biomassa da parte aérea e total, observando-se, todavia, baixo acúmulo de sódio nas folhas, o que impossibilitou concluir sobre algum efeito benéfico da zeólita em I. coccínea sob estresse salino. 
Qualidade de uvas cv rubi revestidas com gel de Aloe vera L. na pré-colheita
No full textThe use of edible coatings is one of the technologies that has been studied for the maintenance of postharvestquality of fruits; they can function as a barrier for water loss, change gas exchange, and improve fruitappearance. Aloe vera gel, which is rich in polysaccharides, is one of the of coatings that has been tested forthis purpose. In this context, the objective of this work was to evaluate the effect of pre-harvest application ofA. vera gel in the post-harvest quality of Rubi grapes. The treatments used were: A. vera gel at the rates of 100,200, and 300 mL L-1, chitosan (160 g L-1), and distilled water (control). The following post-harvest characteristicswere evaluated: titratable acidity (TA), soluble solid (SS) contents, SS/TA, color indexes (brightness, hue, andchroma), and anthocyanin contents. The coatings with Aloe vera gel L. improved the post-harvest quality ofRubi grapes, by decreasing titratable acidity, increasing SS/TA, and improving color indexes. The coatings alsoincreased anthocyanin contents. Thus, the use Aloe vera gel is recommended for the coating of Rubi grapes inthe pre-harvest period.
Uma das tecnologias que vem sendo estudada para a manutenção da qualidade pós-colheita de frutos é o uso de revestimentos comestíveis, que podem funcionar como uma barreira para a perda de água, alterar as trocas gasosas, além de conferir uma boa aparência ao fruto. Um dos revestimentos que vem sendo testado para esta finalidade é o Gel de Aloe vera, sendo um produto bastante rico em polissacarídeos. Neste contexto, o trabalho teve como objetivo avaliar o efeito da aplicação pré-colheita de gel de A. vera na qualidade pós-colheita de uvas cv. Rubi. Os tratamentos foram os seguintes: gel de A. vera nas doses de 100, 200, 300 mL L-1, quitosana (160 g L-1), e a testemunha (água destilada). Foram avaliadas as seguintes características pós-colheita: acidez titulável (AT), sólidos solúveis (SS), relação SS/AT, índices de coloração (Luminosidade, Hue e Croma) e teor de antocianinas. Observou-se que os revestimentos com gel de Aloe vera L. melhoraram a qualidade pós-colheita das uvas cv. Rubi, tendo reduzido a acidez titulável e aumentado a relação SS/AT, além da melhoria dos índices de coloração. Também aumentou o conteúdo de antocianinas, sendo recomendado o uso gel de Aloe vera para revestir uvas cv
Nitrogen doses and splitting in top dressing in the production and macronutrient content in fruits of zucchini
Get PDFNitrogen fertilization in cucurbits must be splitted, one part being supplied before planting and the rest applied in top dressing. However, there is a lack of research about this splitting throughout the cycle. The objective of this study was to evaluate the effect of nitrogen doses and splitting of this fertilization in top dressing on production and macronutrient content in fruits of zucchini. Two experiments were carried out, with thirteen treatments, in the factorial scheme 4x3+1, with four nitrogen doses in top dressing (62.5, 125.0, 187.5, 250.0 kg ha-1 of N), three splitting forms (1/6+1/3+1/2; 1/4+1/2+1/4; 1/3+1/3+1/3 of total dose in each application) and one treatment without fertilization in top dressing (control = dose zero), with four replicates. Experiment 1 and 2 were conducted in 2014 and 2015, respectively. Total and commercial fruit production (g), total and commercial fruit number per plant, length, diameter and average commercial fruit weight were evaluated. Only in experiment 2 the macronutrient content in the fruits were evaluated. In experiment 1, the 1/4+1/2+1/4 splitting provided greater number of total and commercial fruits per plant. In experiment 2, the increasing of the doses in the 1/6+1/3+1/2 and 1/3+1/3+1/3 splitting resulted in a linear increase in total and commercial fruit production. The decreasing order of macronutrient content in fruits was K>N>P>Ca>Mg>S
Productivity and physiology of kale inoculated with entomopathogenic fungi of Amazon region to control caterpilla
Get PDFThe use of biological control agents such as entomopathogenic fungi is an alternative for the control of kale(Brassica oleracea L.) defoliating caterpillars. The objective was to investigate the efficacy of entomopathogenicfungi of Amazon region in the control of defoliating caterpillars in kale and their impacts on the physiologicaland agronomic responses of the crop. Field and greenhouse experiments were conducted in randomized blockdesign and completely randomized design, respectively. The treatments consisted in the application of isolatesof entomopathogenic fungi: Beauveria bassiana, Isaria sp., Metarhizium anisopliae and Trichoderma asperellum.The control treatment consisted of the application of an chemical insecticide based on deltamethrin.Variablesreferring to the development, yield and physiology of the plants were evaluated. Field results revealed thatplants treated with the fungi B. bassiana, M. anisopliae and T. asperellum showed levels of severity, number ofleaves and commercial yield that did not differ from the standard treatment; however, they showed a lowerpopulation density of the defoliating caterpillar complex. The application of the treatments with M. anisopliaeand chemical insecticide showed better photosynthetic performance. In greenhouse, the fungus T. asperellumprovided greater plant height and robustness index in relation to the treatment with chemical insecticide.The entomopathogenic fungi of Amazon region can be contributed to the integrated management of leafdefoliating caterpillars in kale. These microorganisms have similar efficiency with chemical insecticides, beingecologically and economically viable to mitigate the negative impacts caused by the systematic use ofchemicals
Nutritional diagnosis of nitrogen and phosphorus in Ocimum basilicum L. plants grown under macronutrient applications
Get PDFThe objective of this work was to assess the nutritional status of basil (Ocimum basilicum L.) plants grown under application of macronutrients, in a Typic Hapludult. The experiment was conducted in Cruz das Almas, BA, Brazil, in a greenhouse. The treatments were based on a Baconian matrix statistical arrangement, in which one of the nutrients is supplied in different quantities, whereas the other nutrients are maintained at the reference rates. Six nutrients, nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg) and sulfur (S) were evaluated at three different rates. Two additional treatments were used (reference rates; and without nutrient applications), totaling 20 treatments. A completely randomized experimental design with five replications was used, totaling 100 experimental units. Plant material was collected 50 days after treatment applications and dried in an oven for 72 hours. Approximately 0.1 g of dry weight of leaves, stems, and roots were subjected to acid digestion in a mixture of concentrated sulfuric acid and hydrogen peroxide. The digested material was diluted in 100 mL of distilled water to obtain the extract for nutritional diagnosis. The optimal maximum N and P accumulations in basil leaves for high plant performances were 51 and 3.0 g kg-1, respectively. The estimated rates for each nutrient to provide the optimal total N accumulation in basil plants were: N = 235.61, P =91.27, K = 175, S = 41.98 (mg dm-3), Ca = 0.97, and Mg = 0.36 (cmolc dm-3).The objective of this work was to assess the nutritional status of basil (Ocimum basilicum L.) plants grown under application of macronutrients, in a Typic Hapludult. The experiment was conducted in Cruz das Almas, BA, Brazil, in a greenhouse. The treatments were based on a Baconian matrix statistical arrangement, in which one of the nutrients is supplied in different quantities, whereas the other nutrients are maintained at the reference rates. Six nutrients, nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg) and sulfur (S) were evaluated at three different rates. Two additional treatments were used (reference rates; and without nutrient applications), totaling 20 treatments. A completely randomized experimental design with five replications was used, totaling 100 experimental units. Plant material was collected 50 days after treatment applications and dried in an oven for 72 hours. Approximately 0.1 g of dry weight of leaves, stems, and roots were subjected to acid digestion in a mixture of concentrated sulfuric acid and hydrogen peroxide. The digested material was diluted in 100 mL of distilled water to obtain the extract for nutritional diagnosis. The optimal maximum N and P accumulations in basil leaves for high plant performances were 51 and 3.0 g kg-1, respectively. The estimated rates for each nutrient to provide the optimal total N accumulation in basil plants were: N = 235.61, P =91.27, K = 175, S = 41.98 (mg dm-3), Ca = 0.97, and Mg = 0.36 (cmolc dm-3)
Piper nigrum allelopathy on the germination and initial growth of Lactuca sativa and Panicum maximum
Get PDFThe increased demand for food promotes greater use of agricultural inputs and pesticides used in pest control. Many of these products have negative environmental and public health impacts. Thus, there is a need for alternative products, with allelopathic capacity that reduce such impacts. The objective of this work was to verify the allelopathic potential of Piper nigrum L. extracts on the germination and initial growth of Panicum maximum Jacq. and Lactuca sativa seeds. The experimental design used was completely randomized, using two plant organs (leaf and seed), three extractors (hexane, ethyl acetate and methanol) and five concentrations (0 mg/L, 200 mg/L, 400 mg/L, 600 mg/L and 800 mg/L). It was verified the influence of these extracts on germination speed index (IVG), germination percentage (G), mean germination time (TMG), allelopathy index (IA), shoot growth (CPA) and in the root growth (CR) of seeds and seedlings. The leaf and seed extracts, at all concentrations and extractors tested, did not show phytotoxicity or had a very small inhibitory effect on germination and initial growth of Lactuca sativa. For Panicum maximum, ethyl acetate and methanol seed extracts, at the highest concentrations tested, had the most significant negative effects on the weed. Thus, it was possible to infer that extracts from Piper nigrum seeds have potential use in the control of the weed Panicum maximum.The increased demand for food promotes greater use of agricultural inputs and pesticides used in pest control. Many of these products have negative environmental and public health impacts. Thus, there is a need for alternative products, with allelopathic capacity that reduce such impacts. The objective of this work was to verify the allelopathic potential of Piper nigrum L. extracts on the germination and initial growth of Panicum maximum Jacq. and Lactuca sativa seeds. The experimental design used was completely randomized, using two plant organs (leaf and seed), three extractors (hexane, ethyl acetate and methanol) and five concentrations (0 mg/L, 200 mg/L, 400 mg/L, 600 mg/L and 800 mg/L). It was verified the influence of these extracts on germination speed index (IVG), germination percentage (G), mean germination time (TMG), allelopathy index (IA), shoot growth (CPA) and in the root growth (CR) of seeds and seedlings. The leaf and seed extracts, at all concentrations and extractors tested, did not show phytotoxicity or had a very small inhibitory effect on germination and initial growth of Lactuca sativa. For Panicum maximum, ethyl acetate and methanol seed extracts, at the highest concentrations tested, had the most significant negative effects on the weed. Thus, it was possible to infer that extracts from Piper nigrum seeds have potential use in the control of the weed Panicum maximum