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Search Results: 1 - 10 of 402106 matches for " Witter Márcio "
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Produtividade de frutos de meloeiro cultivado em substrato com três solu??es nutritivas
Andriolo, Jer?nimo L.;Lanzanova, Mastrangello E.;Witter, Márcio;
Horticultura Brasileira , 2003, DOI: 10.1590/S0102-05362003000300013
Abstract: the fruit yield of muskmelon plants grown in substrate under three nutrient solutions was obtained. the experiment was conducted in a polyethylene tunnel at the universidade federal de santa maria, brazil. sowing was done on 19th july 2001, in polystyrene trays, using a commercial substrate. on 32 days after sowing, each plant was transferred to a 4.5 l bag, placed inside the tunnel using 1.0 m between rows and 0.3 m within each bag row. during the growing period, plants were trained vertically and two fruits were kept to set in each plant. exceeding fruits were picked out twice a week. treatments consisted of three nutrient solutions, used in the commercial production of muskmelon crops. treatment 1 (t1) was the nutrient solution recommended for growing this crop in nft system in s?o paulo state and treatments 2 (t2) and 3 (t3) were those used in substrate in france and in spain, respectively. in all treatments, 1 l of nutrient solution was supplied weekly to each plant by fertigation. from 35 to 63 days after planting, plant leaf surface was determined weekly by non destructive measurements. fruit yield, at the end of the experiment was significantly higher on plants supplied with t2 and t3 nutrient solutions when compared with t1 treatment. however, no significant difference was found between t2 and t3 treatments.
Acumula??o de massa seca e rendimento de frutos de tomateiro cultivado em substrato com cinco doses de solu??o nutritiva
Rattin, Jorge E.;Andriolo, Jer?nimo L.;Witter, Márcio;
Horticultura Brasileira , 2003, DOI: 10.1590/S0102-05362003000100005
Abstract: we evaluated the effect of five doses of nutrient solution on dry matter accumulation and fruit yield of tomato plants, hybrid monte carlo, grown in substrate inside a polyethylene greenhouse. sowing was done on august 9th, 1999, and 32 days later plants were transferred to bags with 4.5 l of a commercial substrate, at a plant density of 3.3 plants/m2.as reference we used a nutrient solution containing, in mmol/l: kno3, 40; ca(no3)2, 27; mgso4, 12, complemented by 1.5 g/l of superphosphate (20% p2o5), 0.13 ml/l of fe-chelate and 0.66 ml/l of a mixture of micronutrients. the t3 treatment was equal to the reference nutrient solution, whereas in treatments t1, t2, t4 and t5 quantities of all nutrients from t3 were multiplied by 0.25; 0.50; 1.25 e 1.50, respectively. in each treatment, the volume of 1 l of nutrient solution was supplied to each plant once a week by fertigation. plant dry mass accumulation was determined at 138 days after sowing, and fruit yield at the end of the growing period. data from total shoot dry mass fitted well on a linear regression, whereas from vegetative dry mass, leaf area index and fruit yield a quadratic model was adjusted. the concentration of 101.5 mmoln/l, with the proportion among other nutrients of the nutrient solution being respected, was considered as the one to be used to reach the maximum fruit yield of this crop grown in substrates.
Nitrogen concentration in dry matter of the fifth leaf during growth of greenhouse tomato plants
Rattin, Jorge E.;Andriolo, Jer?nimo L.;Witter, Márcio;
Horticultura Brasileira , 2002, DOI: 10.1590/S0102-05362002000400023
Abstract: the nitrogen concentration in dry matter of the fifth leaf during growth of a greenhouse tomato crop was determined. plants of hybrid monte carlo were grown in 4.5 l bags, using a commercial substrate, in a plant density of 3.3 plants m-2. a nutrient solution containing, in mmol l-1: kno3, 4.0; k2so4, 0.9; ca(no3)2, 3.75; kh2po4, 1.5; mgso4, 1.0; iron chelate 19. 103, was used as reference. microelements were added by a commercial mixture. the t3 treatment was equal to the reference nutrient solution, whereas in treatments t1, t2, t4 and t5 quantities of all nutrients from t3 were multiplied by 0.25, 0.50, 1.25 and 1.50, respectively. in each treatment, the volume of 1 l of nutrient solution was supplied to each plant once a week by fertigation. periodically destructive measurements were made from anthesis to ripening of the first truss, to determine dry matter and n concentration in shoot and in fifth leaf tissues, counted from the apex to the bottom of the plant. five dilution curves were fitted from data of n concentration in the fifth leaf and shoot dry matter accumulation during growth of plants. a general relationship was adjusted between actual n concentration in shoot (nt) and in the fifth leaf (nf): nt = 1.287 nf (r2 = 0.80). this relationship could be used to estimate the n status of plants by means of a nitrogen nutrition index (nni), from analysis of the fifth leaf sap.
Crescimento, desenvolvimento e produtividade do tomateiro cultivado em substrato com três concentra??es de nitrogênio na solu??o nutritiva
Andriolo, Jer?nimo Luiz;Ross, Tiago Dal;Witter, Márcio;
Ciência Rural , 2004, DOI: 10.1590/S0103-84782004000500019
Abstract: the effect of three n concentrations of the nutrient solution on growth and yield of tomato plants grown in substrate was determined in autumn and spring growing periods. two experiments were conducted inside a polyethylene tunnel, at departamento de fitotecnia - ufsm, using the hybrid monte carlo. sowing was made on february 8 and on july 5, 2002, and planting inside the tunnel 36 and 40 days later, in autumn and spring, respectively. plants were grown in plastic bags filled with 5.5dm3 of commercial substrate (plantmax?), with one plant per bag and a plant density of 3.3 plants m-2. nutrients were supplied to plants by a complete nutrient solution, with the following composition, in mmol l-1: 5.5 of kno3; 1.3 of kh2po4; 2.75 of ca(no3)2; 0.75 of mgso4, with iron chelate and micronutrients. the treatment t2 was the nutrient solution described above, with 11.0mmoln l-1. for treatment t1, the n concentration of the nutrient solution was reduced to 5.5mmoln l-1, whereas for t3 it was increased to 15.16mmoln l-1. a randomised experimental design was used, with four replications and 15 plants per plot. plants were harvested at 33, 48, 55, 62, 69, 76 and 83 days after planting (dap) in autumn, and at 55, 62, 69, 78, 85 and 92 dap in spring, to measure plant growth and development. crop yield was determined by fresh weight of fruits. the number of leaves was lower on t3 plants in autumn and spring, whereas the number of fruits was higher on t1 plants in spring. the dynamics of fruit dry mass accumulation did not show significant differences among treatments in autumn. in spring, the lowest value of this variable was recorded on t3 plants. mean values of fresh fruit weight reached 5.4; 5.5 and 5.2kg m 2 in autumn, and 6.7; 7.7 and 5.8kg m-2 in spring, for t1 t2 and t3, respectively, fitting well a polynomial model with estimated maximum fruit yield of 7.8kg m-2 at a n concentration of 9.3mmoln l-1. it was concluded that n concentration of the nutrient solution affected the
Produtividade de frutos de meloeiro cultivado em substrato com três solu es nutritivas
Andriolo Jer?nimo L.,Lanzanova Mastrangello E.,Witter Márcio
Horticultura Brasileira , 2003,
Abstract: Comparou-se o rendimento de frutos de meloeiro cultivado em substrato com três solu es nutritivas, no interior de um túnel alto de polietileno, na UFSM, RS. A semeadura foi feita em 19/07/01 em bandejas de poliestireno e 32 dias depois as mudas foram transferidas para sacolas de polietileno contendo 4,5 L de substrato comercial, no espa amento de 1,0 m entre fileiras e 0,30 m entre sacolas. Durante o ciclo da cultura, as plantas foram conduzidas verticalmente e dois frutos foram deixados em cada planta, removendo-se os frutos excedentes duas vezes por semana. Os tratamentos constituíram-se de três solu es nutritivas, empregadas no cultivo comercial do meloeiro. No tratamento 1 (T1) foi utilizada a solu o recomendada no estado de S o Paulo para o cultivo dessa espécie em NFT e nos tratamentos 2 (T2) e 3 (T3) utilizaram-se as solu es recomendadas para o cultivo da mesma espécie em substrato na Fran a e na Espanha, respectivamente. Em cada tratamento aplicou-se o volume de 1 L de solu o para cada planta, em intervalos semanais, via fertirriga o. A área foliar foi estimada semanalmente a partir de medidas n o destrutivas no período entre os 35 e 63 dias após o plantio. A produtividade de frutos determinada ao final do experimento apresentou valores mais elevados nas plantas que receberam as solu es nutritivas T2 e T3, as quais n o diferiram significativamente entre si.
Nitrogen concentration in dry matter of the fifth leaf during growth of greenhouse tomato plants
Rattin Jorge E.,Andriolo Jer?nimo L.,Witter Márcio
Horticultura Brasileira , 2002,
Abstract: The nitrogen concentration in dry matter of the fifth leaf during growth of a greenhouse tomato crop was determined. Plants of hybrid Monte Carlo were grown in 4.5 L bags, using a commercial substrate, in a plant density of 3.3 plants m-2. A nutrient solution containing, in mmol L-1: KNO3, 4.0; K2SO4, 0.9; Ca(NO3)2, 3.75; KH2PO4, 1.5; MgSO4, 1.0; iron chelate 19. 103, was used as reference. Microelements were added by a commercial mixture. The T3 treatment was equal to the reference nutrient solution, whereas in treatments T1, T2, T4 and T5 quantities of all nutrients from T3 were multiplied by 0.25, 0.50, 1.25 and 1.50, respectively. In each treatment, the volume of 1 L of nutrient solution was supplied to each plant once a week by fertigation. Periodically destructive measurements were made from anthesis to ripening of the first truss, to determine dry matter and N concentration in shoot and in fifth leaf tissues, counted from the apex to the bottom of the plant. Five dilution curves were fitted from data of N concentration in the fifth leaf and shoot dry matter accumulation during growth of plants. A general relationship was adjusted between actual N concentration in shoot (Nt) and in the fifth leaf (Nf): Nt = 1.287 Nf (R2 = 0.80). This relationship could be used to estimate the N status of plants by means of a nitrogen nutrition index (NNI), from analysis of the fifth leaf sap.
Acumula o de massa seca e rendimento de frutos de tomateiro cultivado em substrato com cinco doses de solu o nutritiva
Rattin Jorge E.,Andriolo Jer?nimo L.,Witter Márcio
Horticultura Brasileira , 2003,
Abstract: Avaliou-se o efeito de cinco doses de solu o nutritiva sobre a acumula o de massa seca e rendimento de frutos do tomateiro, híbrido Monte Carlo, cultivado em substrato no interior de uma estufa de polietileno. A semeadura foi feita em 09/07/99 e 32 dias após as mudas foram transferidas para sacolas de polietileno com 4,5 L de substrato comercial, na densidade de 3,3 plantas/m2. Foi empregada como referência uma solu o nutritiva contendo, em mmol/L: 40 de KNO3; 27 de Ca(NO3)2; 12 de MgSO4, complementada por 1,5 g/L de superfosfato simples, 0,13 ml/L de Fe quelatizado e 0,66 ml/L de uma solu o de micronutrientes. O tratamento T3 foi igual à dose de referência e os demais tratamentos foram fixados em doses múltiplas de T3, multiplicando-se as quantidades de todos os nutrientes por 0,25; 0,50; 1,25 e 1,50, para os tratamentos T1, T2, T4 e T5, respectivamente. Em cada tratamento, o volume de 1 L de solu o foi aplicado para cada planta em intervalos semanais, por fertirriga o. Determinou-se o acúmulo de massa seca aos 138 dias após a semeadura e a produtividade de frutos maduros ao final do ciclo da cultura. A resposta da acumula o de massa seca total da parte aérea e de frutos se ajustou a uma equa o linear, enquanto a massa seca vegetativa, o índice de área foliar e a produtividade se ajustaram a um modelo quadrático. A concentra o de 101,5 mmolN/L, com a devida propor o entre os demais nutrientes, foi estimada como aquela a ser empregada para atingir a produtividade máxima de frutos dessa cultura cultivada em substratos.
Crescimento, desenvolvimento e produtividade do tomateiro cultivado em substrato com três concentra es de nitrogênio na solu o nutritiva
Andriolo Jer?nimo Luiz,Ross Tiago Dal,Witter Márcio
Ciência Rural , 2004,
Abstract: Determinou-se o efeito de três concentra es de N da solu o nutritiva sobre o crescimento e produtividade do tomateiro cultivado em substrato, no outono e na primavera. Os experimentos foram conduzidos no interior de um túnel alto de polietileno, no Departamento de Fitotecnia da UFSM, empregando-se o híbrido Monte Carlo. As semeaduras foram feitas em 8 de fevereiro e 5 de julho de 2002 e o plantio no interior do túnel aos 36 e 40 dias após a semeadura, no outono e na primavera, respectivamente. Foi empregada uma sacola para cada planta, contendo 5,5dm3 de substrato comercial (Plantmax ), com uma planta por sacola e densidade de 3,3 plantas m-2. Os nutrientes foram fornecidos através de uma solu o nutritiva contendo, em mmol L-1: 5,5 de KNO3; 1,3 de KH2PO4; 2,75 de Ca(NO3)2; 0,75 de MgSO4, com adi o de ferro quelatizado e micronutrientes. O tratamento T2 foi igual a solu o de referência, com 11,0 mmolN L-1. No tratamento T1, a concentra o de nitrogênio da solu o nutritiva foi reduzida para 5,5mmolN L-1, enquanto em T3 foi aumentada para 15,16mmolN L-1. O delineamento experimental empregado foi o inteiramente casualizado, com quatro repeti es e 15 plantas por parcela. Foi feita análise do crescimento e desenvolvimento mediante coleta de plantas aos 33, 48, 55, 62, 69, 76 e 83 dias após o plantio (DAP), no outono, e aos 55, 62, 69, 78, 85 e 92 DAP, na primavera. A produtividade foi medida através da massa verde de frutos. O número de folhas foi inferior nas plantas de T3, no outono e na primavera, enquanto o número de frutos foi mais elevado nas plantas de T1 no cultivo de primavera. A massa seca de frutos no outono evoluiu sem diferen as significativas entre os três tratamentos. Na primavera, essa variável foi inferior nas plantas de T3 ao final do experimento. A produtividade de frutos atingiu valores médios de 5,4; 5,5 e 5,2kg m-2 no outono e de 6,7; 7,7 e 5,8kg m-2 na primavera, respectivamente para T1, T2 e T3, com produtividade máxima estimada de 7,8kg m-2 na dose de 9,3mmolN L-1. Concluiu-se que a concentra o de N na solu o nutritiva afetou o crescimento e a produtividade da cultura do tomateiro em substrato, porém n o foi observada resposta similar nos dois ciclos de cultivo.
High density of defoliated tomato plants in protected cultivation and its effects on development of trusses and fruits
Sandri, Miguel A.;Andriolo, Jer?nimo L.;Witter, Márcio;Ross, Tiago dal;
Horticultura Brasileira , 2002, DOI: 10.1590/S0102-05362002000300018
Abstract: tomato fruit setting on high density defoliated tomato plants with similar leaf area index was determined in three environmental conditions, inside polyethylene tunnels. experiment 1 was carried out in autumn when average solar radiation received by the crop was 8.0 mj m-2 day-1. average external temperature was 18.1oc. experiments 2 and 3 were conducted in spring, when average external temperature was 19.7oc. in experiment 2, average solar radiation received by the crop was 12.4 mj m-2 day-1, whereas in experiment 3 it was reduced to 5.9 mj m-2 day-1 by a 52% shading net. plants were grown in bags, spaced 1.0 m between row and 0.3 m within row bags distance, using 5.5 l of a commercial substrate. nutrients and water were supplied by means of a nutrient solution, delivered daily in order to replace volumes lost by transpiration. treatments consisted of one (t1), two (t2) and three (t3) plants per bag, leading to plant densities of 3.3, 6.7 and 10 plants m-2, respectively. in t1, three leaves per sympod were kept, with a ratio of 3:1 between number of leaves and inflorescences per sympod. in t2, two and one leaf was kept respectively on two consecutive sympods, alternatively on both plants. the ratio between number of leaves and inflorescences was 3:2. in t3, with three plants per bag, only one leaf per sympod was kept on each plant. the ratio between number of leaves and inflorescences was 3:3. in all experiments, the number of trusses per area in t2 and t3 was two and three times higher than in t1, respectively. the number of fruits per unit ground area was lower in t1 plants and similar in t2 and t3 plants in the first experiment, whereas in the second and third experiments similar values were observed among treatments. results indicated that tomato plants adjust the number of fruits, and exceeding flowers are aborted. the use of a plant density of 6.7 plants m-2 combined with a 3:2 ratio between number of leaves and inflorescences per unit ground area seems to be
High density of defoliated tomato plants in protected cultivation and its effects on development of trusses and fruits
Sandri Miguel A.,Andriolo Jer?nimo L.,Witter Márcio,Ross Tiago dal
Horticultura Brasileira , 2002,
Abstract: Tomato fruit setting on high density defoliated tomato plants with similar leaf area index was determined in three environmental conditions, inside polyethylene tunnels. Experiment 1 was carried out in autumn when average solar radiation received by the crop was 8.0 MJ m-2 day-1. Average external temperature was 18.1masculineC. Experiments 2 and 3 were conducted in spring, when average external temperature was 19.7masculineC. In experiment 2, average solar radiation received by the crop was 12.4 MJ m-2 day-1, whereas in experiment 3 it was reduced to 5.9 MJ m-2 day-1 by a 52% shading net. Plants were grown in bags, spaced 1.0 m between row and 0.3 m within row bags distance, using 5.5 L of a commercial substrate. Nutrients and water were supplied by means of a nutrient solution, delivered daily in order to replace volumes lost by transpiration. Treatments consisted of one (T1), two (T2) and three (T3) plants per bag, leading to plant densities of 3.3, 6.7 and 10 plants m-2, respectively. In T1, three leaves per sympod were kept, with a ratio of 3:1 between number of leaves and inflorescences per sympod. In T2, two and one leaf was kept respectively on two consecutive sympods, alternatively on both plants. The ratio between number of leaves and inflorescences was 3:2. In T3, with three plants per bag, only one leaf per sympod was kept on each plant. The ratio between number of leaves and inflorescences was 3:3. In all experiments, the number of trusses per area in T2 and T3 was two and three times higher than in T1, respectively. The number of fruits per unit ground area was lower in T1 plants and similar in T2 and T3 plants in the first experiment, whereas in the second and third experiments similar values were observed among treatments. Results indicated that tomato plants adjust the number of fruits, and exceeding flowers are aborted. The use of a plant density of 6.7 plants m-2 combined with a 3:2 ratio between number of leaves and inflorescences per unit ground area seems to be the upper limit in maximizing the number of set fruits of this crop.
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