Cultivo hidropônico do tomateiro do grupo cereja: crescimento, produção e qualidade sob doses de K e sintomas visuais e anatomia sob omissão de nutrientes

• Ano de defesa: 2012
• Autor(a) principal: Maia, Janini Tatiane Lima Souza
• Orientador(a): Martinez, Hermínia Emília Prieto
• Banca de defesa: Costa, Cândido Alves da , Sediyama, Maria Aparecida Nogueira
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Viçosa
• Programa de Pós-Graduação: Doutorado em Fitotecnia
• Departamento: Plantas daninhas, Alelopatia, Herbicidas e Resíduos; Fisiologia de culturas; Manejo pós-colheita de
• País: BR
• Palavras-chave em Português: Lycopersicon esculentum; Nutrição mineral; Cultivo hidropônico
• Palavras-chave em Inglês: Lycopersicon esculentum; Mineral nutrition; Hydroponic cultivation
• Área do conhecimento CNPq: CNPQ::CIENCIAS AGRARIAS
• Link de acesso: http://locus.ufv.br/handle/123456789/1177

The tomato is on of the most popular vegetables and on of the most demanding in nutrients, and as the development stage, cultivar, temperature, soil, light, humidity and soil management, the average levels of nutrients may vary. Therefore, the aim of this study was to evaluate the cherry tomato, grown in hydroponic system, production, quality and growth under K doses and visual symptoms, the nutrient content and anatomy under omission of nutrients. The experiment was conducted in the greenhouse of the Horticultural Department of the Federal University of Viçosa. In order to evaluate the effect of K doses on yiel and fruit quality of cherry tomato, it was used a completely randomized with four replicates and treatments were increasing levels of potassium (6, 8, 10 and 12 mmol L-1) in the nutrient solution fruiting. We evaluated the production and number of fruits per plant, number of fruits per cluster, fruit weight and cluster, proportion of fruits in different classes, total soluble solids, titratable acidity, ascorbic acid, pH, lycopene, β-carotene and chlorophyll a and b. Also evaluated the levels of nutrients: nitrogen, phosphorus, potassium, calcium, magnesium, sulfur, copper, boron, iron, zinc and manganese in fruits and third leaf above the fourth cluster. It was observed that the dose of 6 mmol L-1 was sufficient to ensure production and quality of cherry tomato plants studied. There was an effect at concentrations of K, Ca, Mg and Mn in tomato fruits with increasing levels of K. The accumulation of K by plants affected the leaf content of Ca, Mg, S, Zn and Mn. Also under K doses, aimed to characterize the growth of cherry tomato plants in completely randomized design in which the treatments were all combinations of the first factor composed of six samples (26, 41, 56, 71, 86 and 101 days after transplant - DAT) and the second factor corresponding to the four potassium (6, 8, 10 and 12 mmol L-1), with a plant as experimental unit. At each harvest was determined the dry mass of leaves, stems, roots, flowers and fruit, leaf area, number of inflorescences and fruits, root length and volume, besides the physiological indices: relative growth rate, reason and leaf area index, net assimilation rate and root-shoot ratio. It was also evaluated the accumulation of nutrients: nitrogen, phosphorus, potassium, calcium, magnesium and sulfur in leaves, stems and roots. The doses of K between 6 and 12 mmol L-1 not influence the growth of cherry tomato. The relative growth rate was reduced during the evaluation period. The accumulation of N, P, K, Ca, Mg and S in leaves were maximum at 101 DAT, reaching respectively: 4850; 35,35; 928,17; 828,39; 228,41 and 190,42 mg. Under omission of nutrients in order to characterize the visual symptoms of deficiency, the effect of nutritional restriction on development and nutrient contents in cherry tomato plants, it was used a completely randomized design with three replications and the treatments were complete solution, omission of N, P, K, Ca, Mg, S, B, Cu, Zn and Fe. After 60 days the plants were removed from solutions and its main symptoms photographed and described. The variables evaluated were: total dry matter production of leaves, stems and roots, number of leaves, flowers and fruits and root volume. It was evaluated the content and accumulation of nutrients: nitrogen, phosphorus, potassium, calcium, magnesium, sulfur, boron, copper, zinc and iron in the leaves stems and roots. According to the observation of deficiency symptoms, the greatest restrictions to the growth of cherry tomato plants were the omissions of P, B and Fe. The nutrients of N, Mg and B were the most affected dry matter production of plants. Concentration and accumulation of nutrients were influenced by deficiencies imposed. In the complete treatment the leaves showed: 3,34; 0,37; 2,07; 2,13; 0,54 and 0,55 dag kg-1 of N, P, K, Ca, Mg and S, and 41,9; 5,9; 4,75; and 94,57 mg kg-1 of B, Cu, Zn and Fe. In treatments in which nutrients were omitted the leaf concentrations were 1,77; 0,22; 1, 57; 1,06; 0,17; 0,10 dag kg-1 of N, P, K, Ca, Mg and S, and 21,35; 4,08; 5,85 and 115,83 mg kg-1 B, Cu, Zn and Fe. Also under omission of nutrients aimed to characterize leaf and stem anatomical changes in cherry tomato plants. The experimental design was completely randomized with three replications and treatments were complete solution, omission of N, Ca, Mg, S and B. After 60 days, the seedlings were taken from solutions, it used leaves with physiological age appropriates to characterize the nutritional deficiency of each nutrient. Also parts of the stem of each plant of about five centimeters in length were used, of the internode just below the third fully expanded leaf from the apex. In each sample leaf characteristics were measured: thickness of the adaxial and abaxial epidermis, palisade and spongy parenchyma, mesophyll, leaf, and the area of tissue components of the midrib epidermis, chlorenchyma, collenchymas, vascular bundle and filling parenchyma. In sections of stem were measured: thickness of the epidermis, chlorophyll parenchyma, collenchymas, filling parenchyma, phloem, exchange track, xylem, filling parenchyma of the mid rib and cell wall of phloem sclereids. Deficiencies of N, Ca, Mg and S caused hypertrophy of the phloem. The lack of Ca and Mg caused the reduction thickness of cell wall of phloem fibers. The most drastic anatomical changes, both on leaves and stems, were caused by the omission of B, as the formation of unorganized vascular bundles, xylem and phloem atypical cell composition and unusual vascular cambium.