ADUBAÇÃO DE PORTA-ENXERTOS DE SERINGUEIRA EM VIVEIRO SUSPENSO

The production of rootstocks in nurseries rubber tree suspended prevents contamination by soil pathogens, however, little information exists about system this fertilization. This study aimed to determine the dosage of nitrogen, phosphorus and potassium in nutrient solution, over growth rubber tree rootstocks. The following concentrations were adopted: 0, 35, 70, 105 and 140 mg plant-1 week-1. The experimental design was randomized blocks, with 4 repetitions. Fertilizers were applied since October 2012 into January 2013. The plot consisted of 10 rootstocks rubber (unknown clone), sustained in the nursery suspended for PET. At 30, 45, 60, 75 and 90 days after application, were evaluated: stalk diameter, plants height, number of leaflets and color index. At 100th day, the final evaluation was carried out measuring the dry weight, foliar area and physiological indices. The dose of 140 mg plant-1 fertigation is the most appropriate for the production of rootstocks nursery suspended. However, the full potential of plant growth was not achieved with the doses tested. To obtain satisfactory results is recommended to use high quality rubber rootstock seeds.A produção de porta-enxertos de seringueira em viveiro suspenso evita a contaminação por patógenos de solo, porém existem poucas informações sobre adubação nesse sistema. Objetivou-se verificar a influência de diferentes concentrações de nitrogênio, fósforo e potássio, em solução nutritiva, sobre o crescimento de porta-enxertos de seringueira em viveiro suspenso. Tratamentos: 0, 35, 70, 105 e 140 mg.planta-1.semana-1, conduzidos num delineamento em blocos casualizados, totalizando 4 repetições. As aplicações foram realizadas de outubro de 2012 a janeiro de 2013. A parcela foi constituída por 10 porta-enxertos de seringueira (clone desconhecido), sustentados no viveiro suspenso por garrafas PET. Aos 30, 45, 60, 75 e 90 dias após a aplicação, foram avaliados: diâmetro do caule, altura de plantas, número de folíolos e índice de cor verde. Aos 100 dias após a aplicação, realizou-se a avaliação final, por meio da massa seca, área foliar e índices fisiológicos. A dose de 140 mg.planta-1 via fertirrigação é a mais adequada para a produção de porta-enxertos em viveiro suspenso. Contudo, o potencial máximo de crescimento das plantas não foi atingido com as doses testadas. Para a obtenção de resultados satisfatórios, é recomendado o uso de sementes de porta-enxertos de seringueira de alta qualidade

PRODUCTION AND PHYSIOLOGICAL QUALITY OF SOYBEAN SEEDS IN ORTHIC QUARTZARENIC NEOSOIL OF THE CERRADO REGION

The aim of this study was to evaluate the effect of the sowing periods in production , productivity component and physiological quality of seeds of three soybean cultivars (TMG133RR, P98Y70RR and NS7670RR) in Orthic Quartzarenic Neosoil in the cerrado region. The design used was a randomized block a factorial scheme design with four repetitions, and each plot with useful space consisted of three rows of four meters length, spaced at 0.45 meters. Field evaluations were the final stand, the height of the plants, height of the first pod insertion, the mass of 100 seeds and productivity. Already in the lab seeds were evaluated for germination and vigor (first germination count, emergency, emergence speed index, length and dry mass of the aerial part of the plant and roots, electrical conductivity, accelerated aging and tetrazolium test). It concludes that it is possible to use Orthic Quartzarenic Neosoils , located in the Cerrado region at altitudes higher than 600 m, in years and places with good water distribution in the spring - summer seasons, for grain and soybeans production, but as a first goal, the crop should be sown in the first 20 days of November otherwise it should take place in early December

PHYSIOLOGICAL QUALITY OF Brachiaria brizantha SEEDS TREATED WITH FUNGICIDE AND INSECTICIDE

This study aimed to evaluate the effects of chemical treatment of seeds with fungicide and insecticide on the seed physiological quality of Brachiaria brizantha cultivar MG5. Two experiments with four replicates were carried out in a completely randomized design. In the first experiment, the seeds were treated with the fungicide pyraclostrobin + fipronil + thiophanate-methyl and in the second, with the insecticide thiamethoxam, both at doses of 0, 150, 300, 450, and 600 mL of commercial product (CP)/100 kg of seeds. Physiological characterization was done on the basis of the first germination count, germination (%), emergence (%), emergence speed index, and length and dry mass of shoot and root. The treatment of B. brizantha seeds with the fungicide pyraclostrobin + fipronil + thiophanate-methyl benefits the physiological quality of seeds, improving germination and root development, with no phytotoxic effect up to the dose of 600 mL of CP/100 kg of seeds. The insecticide thiamethoxam has a biostimulating effect on B. brizantha cultivar MG5 up to the dose of 270 mL of CP/100 kg of seeds, but is phytotoxic in larger doses

ADUBAÇÃO DE PORTA-ENXERTOS DE SERINGUEIRA EM VIVEIRO SUSPENSO

The production of rootstocks in nurseries rubber tree suspended prevents contamination by soil pathogens, however, little information exists about system this fertilization. This study aimed to determine the dosage of nitrogen, phosphorus and potassium in nutrient solution, over growth rubber tree rootstocks. The following concentrations were adopted: 0, 35, 70, 105 and 140 mg plant-1 week-1. The experimental design was randomized blocks, with 4 repetitions. Fertilizers were applied since October 2012 into January 2013. The plot consisted of 10 rootstocks rubber (unknown clone), sustained in the nursery suspended for PET. At 30, 45, 60, 75 and 90 days after application, were evaluated: stalk diameter, plants height, number of leaflets and color index. At 100th day, the final evaluation was carried out measuring the dry weight, foliar area and physiological indices. The dose of 140 mg plant-1 fertigation is the most appropriate for the production of rootstocks nursery suspended. However, the full potential of plant growth was not achieved with the doses tested. To obtain satisfactory results is recommended to use high quality rubber rootstock seeds.A produção de porta-enxertos de seringueira em viveiro suspenso evita a contaminação por patógenos de solo, porém existem poucas informações sobre adubação nesse sistema. Objetivou-se verificar a influência de diferentes concentrações de nitrogênio, fósforo e potássio, em solução nutritiva, sobre o crescimento de porta-enxertos de seringueira em viveiro suspenso. Tratamentos: 0, 35, 70, 105 e 140 mg.planta-1.semana-1, conduzidos num delineamento em blocos casualizados, totalizando 4 repetições. As aplicações foram realizadas de outubro de 2012 a janeiro de 2013. A parcela foi constituída por 10 porta-enxertos de seringueira (clone desconhecido), sustentados no viveiro suspenso por garrafas PET. Aos 30, 45, 60, 75 e 90 dias após a aplicação, foram avaliados: diâmetro do caule, altura de plantas, número de folíolos e índice de cor verde. Aos 100 dias após a aplicação, realizou-se a avaliação final, por meio da massa seca, área foliar e índices fisiológicos. A dose de 140 mg.planta-1 via fertirrigação é a mais adequada para a produção de porta-enxertos em viveiro suspenso. Contudo, o potencial máximo de crescimento das plantas não foi atingido com as doses testadas. Para a obtenção de resultados satisfatórios, é recomendado o uso de sementes de porta-enxertos de seringueira de alta qualidade