Geraldo Milanez de Resende

Efeito de composto orgânico sobre a produção e características comerciais de alface americana

Doses of organic compost were evaluated on crisp head lettuce production and quality in an experiment conduced in Tres Pontas, Brazil, from July 8>th to August 30th. The experimental design was in randomized complete blocks with four replicates, the treatments being constituted by five doses of organic compost (0.0; 20.0; 40.0; 60.0 and 80.0 t ha-1). Total fresh matter showed a quadratic effect, in which the maximum yield of 914.2 g plant-1 was obtained with the dose of 59.4 t ha-1 of organic compost. For commercial fresh matter, the maximum yield (634.3 g plant-1) was obtained with the dose of 56.1 t ha-1. The greatest commercial head circumference (41.4 cm) was obtained with the dose of 53.7 t ha-1. The dose of 42.7 t ha-1 caused a maximum stem length of 3.9 cm. These results permit to conclude that the use of 56.0 t ha-1 of organic compost applied in pre plant provides an increase in yield and commercial quality of crisp head lettuce.

Efeitos de tipos de bandejas e idade de transplantio de mudas sobre o desenvolvimento e produtividade da alface americana

This study was carried out from March to July, 2002 at Tres Pontas, Brazil, to evaluate the influence of tray types and transplanting age of seedlings over the development of crisphead lettuce (Lactuca sativa L.). Three types of tray (128; 200, and 288 cells) and five transplanting ages (22; 26; 30; 34 and 38 days after the sowing) were evaluated in a randomized complete block experimental design (3 x 5 factorial), with three replications. The 128 cells tray and the transplantation at 38 days after sowing date showed the highest fresh mass, driest weight, highest leaf number and highest plant height. The highest commercial yield was obtained with 128 cells tray, followed by the one with 200 cells. The lowest yield was obtained with the 288 cells tray. The transplanting age varied from 22 to 38 days after sowing date depending on the use of the 128 or 200 cells tray, with preference for the smaller periods (22 to 30 days). Using the tray with 288 cells, the seedlings should be transplanted at 38 days after sowing date.

Épocas de plantio e doses de silício no rendimento de alface tipo americana

Com o objetivo de avaliar a influencia de epocas de plantio e doses de silicio sobre o rendimento e qualidade pos-colheita da alface tipo americana, cv. Raider, foram conduzidos dois ensaios nos periodos de maio a agosto de 2002 (inverno) e novembro de 2002 a janeiro de 2003 (verao), no municipio de Tres Pontas-MG. Utilizou-se o delineamento de blocos ao acaso em parcelas subdivididas, sendo as parcelas constituidas pelas epocas de plantio (inverno e verao) e as subparcelas pelas doses de silicio (0,0; 0,9; 1,8; 2,7 e 3,6 L ha-1), com quatro repeticoes. A maior massa fresca total, comercial e circunferencia da cabeca foram obtidas no plantio de inverno. Para os dados relativos as doses de silicio ajustou-se modelo quadratico, pelo qual se estimaram as doses 2,0 e 2,7 L ha-1, como as que proporcionaram os maiores rendimentos de massa fresca total e comercial, respectivamente. Ajustou-se modelo quadratico com ponto de maxima circunferencia para a dose de 2,1 L ha-1 de silicio, que proporcionou circunferencia de 40,1 cm. O plantio de inverno apresentou melhor conservacao pos-colheita que o de verao, quando avaliado por uma escala de notas, aos 10 e 20 dias apos a colheita. Para aplicacao aos 20 dias apos o transplante, evidenciou-se efeito quadratico onde a dose de 2,0 L ha-1 de silicio promoveu a melhor conservacao pos-colheita da alface.The influence of planting times and silicon levels were evaluated on yield and post-harvest quality of crisphead lettuce, cv. Raider. Two trials were carried out in Tres Pontas, Minas Gerais State, Brazil, from May to August of 2002 (winter season) and November to January of 2003 (summer season). A randomized complete block design of split-plots was used, with two planting times applied to the main plots (winter and summer season) and five silicon levels (0.0; 0.9; 1.8; 2.7 and 3.6 L ha-1) applied to the subplots in four replications. The highest total and commercial fresh mass and head circumference were obtained in the winter planting times. A quadratic model adjusted for silicon levels showed that 2.0 and 2.7 L ha-1 levels resulted in the highest yield of total and commercial fresh mass, respectively. A maximum circumference of 40.1 cm was obtained with 2.1 L ha-1 silicon, according to a quadratic model. The winter planting showed better post-harvest conservation than the summer planting when evaluated by a scale at 10 and 20 days after harvest. The application at 20 days after transplantation showed a quadratic effect where 2.0 L ha-1 silicon level promoted the best post-harvest conservation of crisphead lettuce.

Produtividade e qualidade pós-colheita da alface americana em função de doses de nitrogênio e molibdênio

The influence of nitrogen and molybdenum doses was evaluated on the productive characteristics and postharvest quality of crisphead lettuce (Lactuca sativa L.), at Tres Pontas, Minas Gerais State, Brazil, from October to December 2002. A randomized complete block design in a 4 x 5 factorial arrangement with three replications was used. The factorial consisted of four doses of nitrogen (0; 60; 120 and 180 kg/ha) in top dressing, in addition to the usual farmers doses (60 kg/ha), and five doses of molybdenum in foliar application (0.0; 35.1; 70.2; 105.3, and 140.4 g/ha). The highest total fresh weight was obtained with the doses of 86.9 kg/ha of nitrogen in top dressing and 87.4 g/ha of molybdenum. Highest commercial fresh weight was obtained using the doses of 89.1 g/ha of nitrogen in top dressing, while the doses of 94.2 g/ha of molybdenum resulted in the highest yield. The doses of 85.3 kg/ha of nitrogen in top dressing and 72.9 g/ha of molybdenum were the best for highest commercial head circumference. There was no significant effect of the treatments on stem length and post-harvest conservation. The highest percentage of dry matter was obtained with the doses of 89.9 kg/ha of N in top dressing and 77.2 g/ha of Mo in foliar spray.

Doses e épocas de aplicação de nitrogênio sobre a produtividade e características comerciais de alho

O trabalho foi conduzido no periodo de abril a outubro de 1991, no Campo Experimental da Universidade Federal de Lavras para avaliar a influencia de doses de nitrogenio e epocas de aplicacao sobre a produtividade e caracteristicas comerciais do alho (Allium sativum L.). Utilizou-se o delineamento de blocos ao acaso no esquema fatorial 5 x 3, compreendendo cinco doses de nitrogenio (40; 60; 80; 100 e 120 kg/ha de N) e tres epocas de aplicacao (30; 50 e 70 dias apos o plantio (dap)) e 3 repeticoes. O nitrogenio e as epocas de aplicacao, atuaram independentemente sobre a produtividade total, observando-se efeito linear com o aumento das doses de nitrogenio e epocas de aplicacao. Houve reducao na produtividade comercial com o aumento das doses de nitrogenio. A dose de N de 40 kg/ha proporcionou as maiores produtividades comerciais independentemente se aplicado aos 30 dap (5.076 kg/ha), 50 dap (5.502 kg/ha) ou 70 dap apos o plantio (4.086 kg/ha). A aplicacao em cobertura mais tardiamente (70 dap) propiciou, de forma geral, as menores produtividades comerciais. Com o aumento das doses de nitrogenio, em funcao das epocas de plantio, verificou-se aumento linear na percentagem de bulbos pseudoperfilhados, sendo que a dose de N de 40 kg/ha e aplicacoes aos 30 dap (30,6%); 50 dap (34,9%) e 70 dap (42,0%), apresentaram as menores percentagens de bulbos pseudoperfilhados. Com a dose de N de 120 kg/ha aplicada aos 30; 50 e 70 dap a incidencia de bulbos pseudoperfilhados foi 65,2%; 68,8% e 64,8%, respectivamente. Para peso medio de bulbo observou-se efeitos lineares para doses de nitrogenio e epocas de aplicacao, assim como constatou-se aumento no numero de bulbilhos por bulbo, com o incremento das doses de nitrogenio.

Comportamento de cultivares de alface americana em Santo Antônio do Amparo

The behavior of crisphead lettuce cultivars at two planting periods was evaluated in two experiments carried in Santo Antonio do Amparo, Minas Gerais State, Brazil, from September to December 1998 and February to May 1999, under a plastic tunnel conditions. The experimental design was a randomized complete block with six treatments (cv Cassino; Legacy; Lucy Brown; Lorca; Lady and Raider) with four replications. The evaluations of total and marketable fresh weight, circumference and stem length of the marketable head were carried out when the plants had well formed and compact heads. In the first cultivation period, the cultivars Lady (820,4 g plant-1) and Lucy Brown (790,7 g plant-1) presented higher fresh weight. However, they did not differ from cultivar Lorca (626,6 g plant-1). The cultivars Lady (620.0 g plant-1) and Lucy Brown (559.3 g plant-1) presented the highest yield of marketable fresh weight. The circumference of marketable heads varied from 36.3 to 47.2 cm and the stem length from 3.3 to 4.5 cm. No significant differences were observed among cultivars for total and commercial fresh mass in the second planting time; However, all cultivars presented commercial fresh mass above 850 g plant-1. The marketable head circumference varied from 45.4 to 53.4 cm and the stem length from 3.7 to 4.9 cm. Highest yield of fresh mass was obtained in the second planting time.

Avaliação de cultivares de cebola em Petrolina-PE

With the objective of identifying high productive and better quality onion cultivars for the tropical semi-arid region of Brazil, field trials were conducted at Petrolina, Pernambuco State, Brazil, from February until July of 1996.The experimental design was a randomized complete blocks with four repetitions and twenty treatments (Cultivars Granex-429, Texas Grano-PRR, Brownsville, Houston, Texas Grano-502, Texas Grano-438, Conquista, Composto IPA-6, Belem IPA-9, Franciscana IPA-10, Valeouro IPA-11, Alfa Tropical (CNPH-6179), CNPH-5898, CNPH-6074, CNPH-6040, CNPH-6067, Bola P. Empasc, XP-1, XP-2 and Crioula Mercosul). Production of commercial bulbs ranged forms 21.41 to 61.78 ton/ha. Texas Grano-PRR had the highest yield (61.78 ton/ha), followed by Granex-429 (58.28 ton/ha), Texas Grano-438 (56.97 ton/ha), Brownsville (55.38 ton/ha), Texas Grano-502 (53.97 ton/ha) and Houston (53.35 ton/ha).

Características produtivas de cultivares de batata-doce em duas épocas de colheita, em Porteirinha - MG

Com o objetivo de avaliar a produtividade e a qualidade de raizes de cultivares de batata-doce e identificar a melhor epoca de colheita, conduziu-se um experimento no Campo Experimental do Gorutuba, em Porteirinha-MG, de novembro de 1990 a junho de 1991. Foram estudadas cinco cultivares de batata-doce (Brazlândia Branca, Brazlândia Rosada, Brazlândia Roxa, Princesa e Paulistinha) e duas epocas de colheita (150 e 200 dias apos plantio), arranjadas em esquema fatorial 5x2, no delineamento experimental de blocos casualizados, com cinco repeticoes. Verificou-se, para a colheita aos 150 dias apos o plantio, que a cultivar Brazlândia Branca foi 62,7% mais produtiva (22,84 t/ha) que a cultivar Brazlândia Roxa (14,33 t/ha), a menos produtiva. Aos 200 dias de ciclo, a cultivar Paulistinha foi a mais produtiva (54,50 t/ha), sendo a menor produtividade apresentada pela cultivar Brazlândia Rosada (55,0% menos produtiva que a cultivar Paulistinha). A cultivar Brazlândia Roxa apresentou maior producao de refugos, de 7,76 e 12,38 t/ha, respectivamente, para a colheita aos 150 e aos 200 dias apos o plantio. Para peso medio de raiz, houve uma variacao de 220,12 a 504,95 g, sendo que todas as cultivares apresentaram maior porcentagem de raizes graudas (400-800 g/raiz), quando colhidas mais tardiamente. Recomenda-se a colheita das cultivares Paulistinha, Brazlândia Rosada e Brazlândia Branca aos 150 dias apos o plantio, pelo tamanho menor de raizes preferidas pelo consumidor. Ja para a cultivar Princesa, em funcao da sua menor producao de raizes tipo 2 (400 a 800 g/raiz) comparativamente as cultivares anteriores, sua colheita pode ser feita de 150 ate 200 dias apos o plantio. A cultivar Brazlândia Roxa apresentou melhor desempenho quando colhida aos 200 dias apos o plantio.

Produtividade e qualidade pós-colheita de cebola adubada com doses crescentes de nitrogênio e potássio

This study was carried out from March to September 2000, in Petrolina, Pe rnambuco State, Brazil, to evaluate the influence of nitrogen and potassium levels on yield characteristics and post-harvest quality of onion bulbs (Allium cepa L.). The cultivar Franciscana IPA-10 was used. The experimental design was a randomized complete block in a 4 x 3 factorial scheme, involving four levels of nitrogen (0; 60; 120 and 180 kg ha-1) and three levels of potassium (0; 90 and 180 kg ha-1) with three replications. The commercial yield showed a linear effect in the absence of potassium fertilization, while the levels of 90 and 180 kg ha-1 of potassium provided maximum yield with the levels of 175.8 and 169.4 kg ha-1 of nitrogen. Increasing the doses of nitrogen resulted in a reduction of the non-commercial yield (culls). In the absence of potassium fertilization, a linear effect was obtained as a result of the levels of nitrogen for fresh mass of the bulb. For the levels of 90 to 180 kg ha-1 of potassium, the highest yield of fresh mass of the bulb was obtained with the level of 153.3 kg ha-1 of nitrogen. The levels of nitrogen influenced the classification of commercial bulbs of onion and the largest percentage of bulbs of the class 3 (85,8%) corresponded the dose of 153,6 kg ha-1 of nitrogen. No significant mass loss occurred after 20 days and only after 40 and 60 days after cure did any significant effects become evident and there was no interaction between the levels of nitrogen and potassium.

Similaridade genética de cultivares de alho pela comparação de caracteres morfológicos, físico-químicos, produtivos e moleculares

Morphological (plant height, number of green leaves, width of leaves, and the insertion angle of the leaves), physical-chemical (soluble solids, the total titratable acidity, and the pH), productive (commercial production and medium weight of the bulbs) and molecular (with RAPD markers) characteristics of garlic were studied. Twelve cultivars, six semi-noble (Gigante Curitibanos, Gigante Roxo, Gigante Roxao, Gravata, Amarante and Cateto Roxo) and six noble (Cacador, Chonan, Contestado 12, Cacador 30, Cacador 40 and Quiteria 595) were analyzed. The results of the similarity analysis among cultivars were equivalent, when morphologic, physical-chemical and productive or molecular characteristics were evaluated, indicating that the methods presented the same resolution to distinguish cultivars, generating two groups: one formed by seminoble and other formed by the noble cultivars.