Antônio Rodrigues Vieira

Inoculação de sementes de milho utilizando o Trichoderma harzianum como promotor de crescimento

Conduziu-se este trabalho com o objetivo de estudar o efeito do fungo Trichoderma harzianum como promotor de crescimento de sementes de milho tratadas com diferentes fungicidas. O experimento foi realizado em vasos em casa-de-vegetacao, adotando o delineamento experimental inteiramente casualizado em esquema fatorial (3x2), utilizando os tratamentos com fungicidas: Captan®, Maxim® e testemunha e inoculacao (com e sem inoculo) em quatro repeticoes. As caracteristicas agronomicas avaliadas foram: altura de planta, peso da materia seca da parte aerea e de raizes e tambem a tecnica de isolamento do fungo nas raizes aos 45 dias apos semeadura. Observou-se diferenca significativa somente para o fator inoculo na caracteristica peso de materia seca de raizes. Pelos resultados obtidos, verificou-se que o fungo Trichoderma harzianum estimulou maior acumulo de materia seca nas raizes das plantas de milho e tambem estava presente nas raizes das plantas oriundas de sementes inoculadas, independentemente do tratamento fungicida das sementes.

Desempenho de sementes de pimentão revestidas com diferentes materiais

The technique of covering seeds has been used mainly for the species which have small seeds, such as vegetables, forage, forest and ornamental species, because besides increasing the size of the seeds for direct sowing, it is possible to add other elements which are necessary for the good development of the plant in its early stages. In this context the objective of the present study was to covered green-pepper seeds in different types of materials and to evaluate their behavior during storage. Seeds treated and not treated with Rovrin at the dosage of 200g/100kg were submitted to pre-conditioning for the imbibing of seeds in KNO3 in -1,1Mpa solution, in an aired system for 5 days. After drying the seeds were covered in a mixture of sand + microcellulose and another of limestone + microcellulose. The covered seeds and those not covered were dried and packed in paper envelopes (permeable pack) and in aluminum envelopes (impermeable pack) and stored at room temperature in the Seeds Analysis Laboratory at UFLA. The seed quality was evaluated once every four months, for a period of 20 months, using the following parameters: water content, germination test, accelerated aging, controlled deterioration and emergency in soil + sand. From the results, it was possible to conclude that the covering of seeds slows but does not affect the germination rate of the green pepper seeds before storage, but the covered seeds deteriorate faster than the seeds not covered, when stored in permeable packs. The nature of the materials used did not affect the quality of the green pepper seeds stored in impermeable packs.

Action of gibberellic acid (GA3) on dormancy and activity of alpha-amylase in rice seeds

This research was carried out in the Laboratory of Seeds Technology and Analysis of the Fitotecnia Department of the Agrarian Science Center of Federal University of Espirito Santo, Alegre, Espirito Santo State, Brazil, out with the objective to evaluated the physiological seed quality to ten soybean genotypes: BRSMG - Garantia, MGBR-46 (Conquista), MGBR 94-7916, FT-104, CAC-1, MGBR 95-19125, BRSMG - 68 (Vencedora), UFV-16, BR 94-12773, Doko, from the 99/2000 crop year, submitted the stress condition through the accelerated aging test, with temperature of 42oC and relative humidity of, approximately, 100% for periods of 0, 24, 48, 72 and 96 hours, utilized the completely randomized design, with four replications of 25 seeds. The physiological quality of seeds was evaluated through by the germination and vigor test (first germination count and radicule length. The results indicate that the genotypes Doko and CAC-1 showed the best physiological seed quality. In order to the accelerated ageing periods above 48 hours determinate results with higher seed deterioration. The total germination decreased until the period of 96 hours of treatment.Para avaliar a eficiencia do acido giberelico (GA3) na superacao da dormencia de sementes de arroz, bem como a atividade da enzima a-amilase como indicador do grau dessa dormencia, foram utilizadas sementes da cultivar irrigada Urucuia, que apresentam alta intensidade de dormencia pos-colheita. Para tanto, as sementes foram submetidas a pre-secagem em estufa de circulacao forcada de ar a 40oC por 7 dias e a submersao em 30 ml de solucoes de GA3 nas concentracoes de 0, 10, 30 e 60 mg/litro de H2O, nos tempos de 2, 24 e 36 horas. Apos os tratamentos, foi determinada a atividade da a-amilase atraves da eletroforese em gel de poliacrilamida e da espectrofotometria. Simultaneamente, foi realizado o teste de germinacao. Pelos resultados, observa-se que houve ganho na germinacao e na atividade da a-amilase em maiores concentracoes e tempos de embebicao das sementes em GA3. A embebicao das sementes em 60 mg GA3/litro H2O por 36 horas apresenta-se eficiente como um tratamento rapido na superacao da dormencia de sementes de arroz, sendo equivalente a estufa de circulacao forcada de ar a 40oC por 7 dias. A atividade da enzima a-amilase apresentou-se como um eficiente marcador do grau de dormencia das sementes.

Tratamento fungicida e peliculização de sementes de soja submetidas ao armazenamento

O tratamento de sementes de soja com fungicidas vem sendo utilizado como importante ferramenta no controle de patogenos. Nesse trabalho, objetivou-se estudar o desempenho de sementes de soja tratadas com fungicidas e peliculizadas, antes e apos o armazenamento. Foram utilizados cinco lotes de sementes, cultivar Monsoy 6101, submetidos aos tratamentos: thiabendazole+thiram sem polimero, carbendazin+thiram sem polimero, sem fungicida (testemunha) sem polimero, alem desses tratamentos realizados via peliculizacao (com polimero). A qualidade fisiologica e sanitaria das sementes foi avaliada inicialmente e apos seis meses de armazenamento em condicoes ambientais, pelas seguintes determinacoes: teor de agua, teste de germinacao, emergencia em bandeja, teste de frio e de sanidade. Conclui-se que a peliculizacao, em associacao com fungicidas, nao afeta a qualidade fisiologica das sementes de soja e o tratamento de lotes de sementes de soja com os fungicidas thiabendazole+thiram e carbendazin+thiram melhora seu desempenho e qualidade sanitaria.The treatment of soybean seeds by fungicides has been used as an important tool in pathogen control. The objective of this work was to verify the performance of soybean seeds treated with fungicide and film coating, prior and after storage. Five seed lots, cultivar Monsoy 6101, were treated with thiabendazole+thiram without polymer, carbendazin+thiram without polymer, without fungicide (control), without polymer, and treatments by film coating (with polymer). The physiological and sanitary quality of the seeds was evaluated initially and after six months storage, under environmental conditions, according to the following characteristics: water content, test of germination and emergence on tray, blotter test and cold test. The film coating associated with fungicides does not affect the physiological quality of soybean seeds and the soybean seed treatment with the fungicides thiabendazole+thiram and carbendazin+thiram improves performance and sanitary quality.

Efeito de diferentes materiais de peletização na deterioração de sementes de tomate durante o armazenamento

The pelleting of vegetable seeds is a very common technique, mainly for the species which have small seeds. One of its functions is to increase the seed size for direct sowing. The present study verified the pelleting of tomato seeds with different types of materials and to evaluated the performance during seed storage. The materials used as pelleting coats were sand + microcellulose and limestone + microcellulose, with and without Rovrin fungicide (200g/100kg of seeds). Raw seeds were covered, and treated with or without fungicides. Then, seeds were dried and put in paper envelopes (permeable) and in aluminum foil (impermeable) and stored at room temperature at the Universidade Federal de Lavras Seed Lab. The evaluation of seed quality was done once every four months, for 24 months, using the following determinations: germination test, accelerated aging and emergence on soil + sand. Covered seeds presented slower germinatnion than the raw seeds. Seeds covered with limestone + microcellulose deteriorated faster than the ones with sand + microcellulose and seeds treated with fungicides in association with the pelletting

Armazenamento de sementes de cafeeiro: ambientes e métodos de secagem

The loss of seed viability, what makes it difficult to keep the high physiological quality, is one the greatest problems faced by the coffee seed producers during seed storage. Thus, the performance of the coffee seeds (Coffea arabica L. cv. Rubi) during storage harvested in 2001/2002, at Federal University of Lavras-Brazil (UFLA), was investigated. After cleaning seeds were kept at 47,5% of water content (WC), fast (forced air chamber at 35oC) and slow (open environment with 20oC and 60% of relative humidity (RH)) dried until reaching 12%. The seeds were packed in hermetic bags and stored for 9 months at two environments: regular, with monitored temperature and RH, and in dry cold chamber at 10oC and 50% of RH. Before storage and every three months seed quality was evaluated by the germination test, seedlings emergency, emergency speed index and tetrazolium test. Fast drying decreases the vigor of seeds independent from where they dry. In cold chamber it is possible to store regular seeds or slowly dried seeds for up to nine months. In a regular warehouse environment the vigor is affected independently from the way they are dried.

Alterações isoenzimáticas em sementes de cultivares de soja em diferentes condições de armazenamento

The objective of this work was to determine the physiological and isozyme alterations in seeds of soybean genotypes, under different storage conditions. A completely randomized experimental design was used with four replicates, in a factorial arrangement with six soybean cultivars (TMG 1176, TMG 1179, TMG 132, TMG 133, TMG 115, and GB 874) and five storage times (0, 2, 4, 6, and 8 months), in two storage environments (a cold and dry chamber, at 10oC and 50% relative humidity; and a conventional warehouse, under uncontrolled conditions). Physiological quality was evaluated by the germination, accelerated aging, and cold tests. Isozyme expressions of malate dehydrogenase (MDH), alcohol dehydrogenase (ADH), esterase (EST), isocitrate lyase (ICL), superoxide dismutase (SOD), and peroxidase (PO) were determined. Soybean seeds stored in cold and dry chambers maintained their physiological quality. After six months storage under uncontrolled conditions, seed quality and isozyme expressions of MDH, ADH, EST, ICL, SOD, and PO lowered. There was no alteration on seed stored in cold and dry chambers. Soybean genotypes show different tolerance levels to storage and isozyme expression.

Tratamentos inseticida, peliculização e inoculação de sementes de soja com rizóbio

Insecticide treatment, film coating and rizobium soybean seed inoculation The treatment of soybean seeds with chemical products to control pests may impair seed quality and the establishment of the rizobium-plant symbiosis. The aim of this work was to evaluate the performance of soybean seeds treated with insecticides and film coating, as well as the nodulation and plant growth. Soybean seeds were treated with insecticides and polymer in a 6x2 factorial scheme. The insecticides used in the treatments were carbosulfan, clotianidina, fipronil, imidacloprid, tiametoxan and a control without insecticides. Insecticides were applied with and without the polymer, as well as the control. Seeds were evaluated by the germination test, cold test and seedling emergence. In addition, they were inoculated with the strains BR86 and BR96, separately, and sowed in Leonard pots. During the flowering, the plants were evaluated using the number and dry matter of nodules and of the aerial part. The insecticide treatments can

Chemical treatment, seed coating and storage of Brachiaria brizantha cv. Marandu seeds

Despite the increasing use of coated seeds in recent years, there is little information available on the behavior of these seeds during storage. Therefore, the aim of this study was to evaluate the effect of different coating materials, in combination with chemical treatments, on seed performance during storage. Seeds of Brachiaria brizantha cv. Marandu provided by WolfSeeds were coated (pelleted) in an adapted concrete mixer using fourteen types of coating and were compared to uncoated control seeds. The combination of these treatments was also evaluated with fungicide and insecticide treatments of the seed. An evaluation was made of the physiological quality from the germination test, seedling emergence and sanitary quality after 0, 3, 6, 9 and 12 months of storage. It was concluded that seeds coated with Sand + PVA and sand + CaSiO3 + PVA or polymer, chemically treated, maintained physiological quality over the 12 months of storage; chemical treatment with the fungicide mixture Carbendazim + Thiram and the insecticide Fipronil on coated or non-coated seed gives effective control of fungi and promotes better physiological performance during storage; the coating with bentonite and/ or limestone negatively affected the seed quality of Brachiaria brizantha cv. Marandu during the 12 months storage period; the seed coating reduced the speed of germination and emergence of Brachiaria brizantha cv. Marandu.

Osmotic conditioning associated with gibberellic acid on physiological quality of sweet pepper seeds harvest in different stage of maturation

5 . RESUMO - Considerando que o condicionamento osmotico e a aplicacao do acido giberelico sao capazes de beneficiar a germinacao e o vigor das sementes, objetivou-se com essa pesquisa verificar o efeito da associacao do condicionamento osmotico com giberelina na qualidade das sementes de pimentao colhidas em diferentes estadios de maturacao. Os frutos foram produzidos em ambiente protegido, utilizando-se os hibridos Magnata Super e Konan R, que foram colhidos em quatro estadios de maturacao, com base na coloracao dos frutos: completamente verdes (estadio 1), com 20 a 30% de coloracao avermelhada (estadio 2), com 40 a 50% de coloracao avermelhada (estadio 3) e completamente vermelhos (estadio 4). As sementes foram condicionadas em solucao de KNO 3 contendo giberelina nas seguintes concentracoes: 0, 50, 100, 200 e 400μM. Foram feitas as seguintes determinacoes em laboratorio: germinacao, emergencia, indice de velocidade de emergencia, condutividade eletrica, analise das enzimas malato desidrogenase, alcool desidrogenase, catalase e proteinas resistentes ao calor. O condicionamento osmotico e o uso da giberelina nao proporcionaram aumentos significativos na germinacao de sementes de pimentao dos dois hibridos. Entretanto favoreceu a velocidade de emergencia, principalmente em sementes colhidas nos estadios 3 e 4. Verificou-se tambem efeito negativo do condicionamento osmotico em sementes colhidas no estadio 1 para ambos os hibridos. Concluiu-se que a associacao dos tratamentos afeta positivamente o vigor das sementes de pimentao, com os melhores resultados verificados em sementes colhidas de frutos no inicio do amadurecimento, com 20 a 50% de coloracao avermelhada. Termos para indexacao: hortalica, priming, regulador de crescimento. ABSTRACT - Considering that osmotic conditioning and gibberellic acid application can benefit germination and seed vigor, the objective of this study was to verify the effect of the association of osmotic conditioning with giberellic aid on the physiological quality of sweet pepper seeds at different maturation stages. The fruits were produced in a protected environment using the Magnata Super and Konan R hybrids, harvested at four maturation stages, based on the fruit coloration: completely green fruits (stage 1), fruits with 20 to 30% of red coloration (stage 2), fruits with 40 to 50% of red coloration