Salomão Lima Guimarães

Características morfológicas e produtivas de feijão guandu anão cultivado em solo compactado

Aliado ao uso indiscriminado de maquinarios agricolas, o manejo inadequado altera a densidade natural do solo causando reducao em sua qualidade fisica e, por conseguinte, implicando em efeitos negativos no desenvolvimento de culturas. Assim, objetivou-se avaliar a influencia de compactacao do solo nas caracteristicas morfologicas e produtivas de feijao guandu anao (Cajanus cajan L. Mill sp.) cv. IAPAR 43 Arata. O experimento foi realizado em casa de vegetacao na Universidade Federal de Mato Grosso - Campus Universitario de Rondonopolis. Utilizou-se um Latossolo Vermelho coletado na profundidade de 0-20 cm. Os tratamentos foram cinco niveis de compactacao (densidades do solo: 1,0; 1,2; 1,4; 1,6 e 1,8 Mg m-3) e seis repeticoes em delineamento experimental inteiramente casualisado. As avaliacoes foram realizadas aos 33 e 63 dias apos a emergencia das plantas, determinando-se numero de ramos, numero de folhas, altura de plantas, diâmetro do caule, producao de massa seca de folhas, colmos, parte aerea e raiz. As caracteristicas morfologicas e produtivas do feijao guandu anao apresentam restricoes quanto aos niveis de compactacao do solo, mostrando-se pouco eficiente na descompactacao em Latossolo Vermelho.

Viabilidade do inoculante turfoso produzido com bactérias associativas e molibdênio

Among the vehicles in use for diazotroph inoculation, peat is considered the most-widely used in Brazil. Peat makes possible the viability of a large number of cells, at the same time protecting them from adversities found in the soil. The objective of this study was to evaluate the viability of peat inoculum developed with diazotroph bacteria and molybdenum. The bacteria BR11417 (Herbaspirillum seropedicae) and BR11340 (Burkholderia sp.) were allowed to multiply for a period of 24 hours, and a sample of 10 ml with 108 cel. mL-1 was transferred to polypropylene bags containing 35 g of peat. Two dosages and two sources of molybdenum were then added: 1.12 and 2.25 g of sodium molybdate and ammonium molybdate respectively. Inoculum with no molybdenum was used as control. With law No. 86955, Brazilian legislation specifies that commercial inoculants based on nitrogen-fixing microorganisms have minimum concentrations of 108 viable cells per gram of product at the time of use, and that viability of the cells be maintained for a period of at least six months. This study showed that without the addition of molybdenum to the inoculum, bacteria survived with a viable-cell total of about 108 cells g-1 of inoculum for a period of up to 110 days. With the addition of molybdenum, the inoculum remained viable for a period of 180 days. The application of molybdenum contributes to the increased viability of peat inoculum produced with the bacterial strains BR11417 and BR11340.

Nitrogen and potassium in production, nutrition and water use efficiency in wheat plants

Wheat ( Triticum aestivum L.) is a cereal used in food and feed for its nutritional properties. For nitrogen and potassium management, efficient use of water is required for greater availability and transportation of these nutrients. The objective of this study was to evaluate the effect of combinations of nitrogen and potassium doses in production, nutrition and water use efficiency in wheat. The experiment was held in a greenhouse with 8-dm3 pots using Oxisol collected at a depth of 0-0.2 m under Cerrado vegetation. Base saturation was raised to 60%. The experimental design was a randomized block in a 5x5 factorial arrangement with five doses of nitrogen (0, 100, 200, 300 and 400 mg dm-3) and potassium (0, 90, 180, 270, 360 mg dm-3) with four replications. Soil moisture was maintained by an auto-irrigation system (3 kPa pressure). The experiment was collected at 95 days after plant emergence. We evaluated the dry mass of ears, shoots and roots, the total dry matter, nitrogen and potassium in grains, and the consumption and efficiency in water use. An analysis of variance and regression test at 5% probability was conducted using SAS statistical software (SAS Institute, Inc., Cary, North Carolina). The nitrogen and potassium alone increased the dry mass of ears by 31.47% and 20.91%, respectively. There was an interaction of nutrients on the dry mass of the shoots and the total dry matter. Potassium increases the concentration of nitrogen. Nitrogen and potassium promote gains in production, nutrition and water use efficiency. Trigo ( Triticum aestivum L.) es un cereal utilizado en la alimentacion humana y animal por sus propiedades nutritivas. En la gestion de nitrogeno y potasio, el uso eficiente del agua es necesaria para la mayor disponibilidad y el transporte de estos nutrientes. Este estudio tuvo como objetivo evaluar el efecto de las combinaciones de nitrogeno y potasio en la produccion, la nutricion y la eficiencia en el uso del agua en trigo. El experimento se realizo en un invernadero con recipientes de 8 dm3. Usando Oxisol, recogido a una profundidad de 0-0,2 m de area bajo la vegetacion del Cerrado. La saturacion de bases se aumento a 60%. El diseno experimental fue de bloques al azar en arreglo factorial 5x5 con cinco dosis de nitrogeno (0, 100, 200, 300 y 400 mg dm-3) y potasio (0, 90, 180, 270 y 360 mg dm-3) con cuatro repeticiones. La humedad del suelo se mantuvo con un sistema autoirrigante (mantenido en el potencial de -3 kPa). El experimento foe cosecho despues de 95 dias de la emergencia. Se evaluaron la materia seca de las espigas, brotes, raices, y materia seca vegetal total; nitrogeno y potasio en granos; el consumo y la eficiencia en el uso del agua. Las variables se sometieron a analisis de varianza y prueba de regresion al 5% de probabilidad por el programa estadistico SAS. El nitrogeno y potasio, por separado, aumentaron el peso seco de las espigas, con incrementos de 31,47 y 20,91%, respectivamente. Hubo interaccion de nutrientes a la masa seca de la parte aerea y total. El potasio aumenta la concentracion de nitrogeno. El nitrogeno y el potasio promueven ganancias en la produccion, la nutricion y la eficiencia en el uso del agua.

Combined inoculation of rhizobia on the cowpea development in the soil of Cerrado

BBiological nitrogen fixation (BNF) plays an important role in the cowpea cultivation. This study aimed to assess the foliar levels of chlorophyll and the yield components of cowpea subjected to combined inoculation of rhizobia in Cerrado soil. The experiment was carried out in field conditions, from December of 2014 to the march of 2015, in Rondonopolis, Mato Grosso, using randomized block design with ten treatments and three replicates. Were tested the single strains MT8 and MT15 (both of R. tropici), MT16 (R. leguminosarum), BR3267 (Bradyrhizobium japonicum), the strains combinations MT8+MT15, MT8+MT16, MT15+MT16, and MT8+MT15+MT16, nitrogen fertilization (70 kg ha-1 of N-urea), and absolute control (without inoculation of rhizobia and without nitrogen fertilization). Data were subjected to analysis of variance and the averages were compared by orthogonal contrast and F test (p≤0.05). Were assessed the Falker chlorophyll index (at the 40 and 60 days after sowing), number and dry matter of nodules (at the 40 days after sowing), number of pods per plant, grains yield, the concentration and accumulation of nitrogen in grains, and crude protein. The number of pods per plant was increased 33.6% in the combination MT8+MT15. The same effect was observed for the yield grain, which presented an increase of 8.7%, 13.8%, and 16.7% in the combinations MT8+MT16, MT15+MT16, and MT8+MT15, respectively. The nitrogen accumulation in the grains increased 42.7% with the inoculation of MT15 strain. The cowpea responds positively to the usage of combinations of rhizobia strains.

Características produtivas e nutricionais do capim-xaraés inoculado com bactérias diazotróficas associativas

The aim of this study was to evaluate yield and nutritional characteristics of Xaraes grass inoculated with diazotrophic associative bacteria in the first cultivation in the Cerrado Oxisol. The experiment was conducted in the greenhouse. The experimental design was completely randomized factorial 6x3 consisting of: three strains of diazotrophic associative bacteria (MTAz8, MTH2 and Y2), a combination of strains MTAz8 and MTH2, nitrogen fertilization and absolute control, and three cuts (30, 60 and 90 days) in five replicates. The inoculation was performed by inserting an aliquot of 5ml of the bacterial broth containing 108 cells ml-1 in the soil near the root zone of each plant. The variables evaluated were: dry weight of shoot, crude protein, accumulation and nitrogen concentration in the shoot and determining the number of nitrogen-fixing bacteria in the soil. The fertilized soil dry matter production increased over the cuts. Among the strains Y2 showed higher accumulation of nitrogen and largest population of bacteria in the middle of the LGI culture. The nutritional characteristics of Xaraes grass declined as the cuts were made.

The inoculation of cowpea culture with rhizobial lineage in Brazilian Cerrado Region

Cowpea culture is spreading in the Brazilian Cerrado Region and specifically in Mato Grosso State. To evaluate the productive characteristics of cowpea inoculated with rhizobia lineages and grown in the Cerrado of Mato Grosso State, we conducted an experiment in a randomized block design with seven treatments, which consisted of five rhizobia lineages. Four lineages were previously isolated from cowpea (MT08, MT15, MT16 and MT23); one was a recommended lineage for cowpea in Brazil (BR3267). Two controls were included: one was equivalent to 75 kg N ha-1 nitrogen and another was without nitrogen fertilization and without inoculation of rhizobia lineage. They were arranged in six blocks totaling 42 parts of 12.5 m² each. At 40 days after sowing (d.a.s.), six plants of ​​each part of floor area were collected to determine the variables plant height, dry mass of shoots and roots, total dry mass, number of nodules, dry mass of nodules, SPAD reading and relative efficiency of each lineage. Data were subjected to analysis of variance using the statistical analysis program SISVAR. To compare the means, it was evaluated with Tukey test at 5% probability and contrast analysis. Regarding the lineage used, the most satisfactory result for plant height was BR3267 lineage; however, there were statistical differences between treatments with nitrogen fertilization. There were significant differences between dry weight of shoots, total dry weight and dry weight of nodules. The BR3267 lineage presented better results in the dry mass of roots and for relative efficiency. The most satisfactory results for SPAD readings and number of nodules were observed in MT15 lineage. The BR3267 and MT15 lineages tested and analyzed had high symbiotic effectiveness for inoculation in cowpea. Key words: Vigna unguiculata, rhizobium, nitrogen fixation.