Growth and nitrogen accumulation by common bean plants originating from seeds with high molybdenum concentration
01/Aug/2008
Common bean (Phaseolus vulgaris) seeds with high molybdenum concentration can adequately supply the crop demand of this nutrient. Two experiments were conducted in a greenhouse to evaluate the effect of Mo-enriched seeds, obtained from plants treated with foliar fertilization, on growth and N accumulation by common bean plants. The soil substrate was the A horizon of a Haplustult (3.5 kg pots), which were limed and fully fertilized with exception of Mo. The first experiment had a 3 x 2 x […]
Soil chemical atributes and common bean yield as affected by lime and manganese rates
01/Jun/2008
Common bean is one of the most important staples in Brazil. The objective of this study was to evaluate the common bean cv. Pérola yield and changes in soil chemical attributes as influenced by liming and manganese rates. The experiment was carried out in pots containing dystrophic Red Yellow Latosol (Oxisol). Treatments consisted of a 2 x 6 factorial combination of two limestone (CO3 and MgCO3 in a 3:1 molar ratio) rates, calculated to increase base saturation to 50 and […]
Traffic-induced compaction of an oxisol and its relation with growth and yield of common bean and wheat
01/Jun/2008
Soil compaction is a limiting factor to increase yields and to develop long-term no-till, especially in clayey soils. The objective of this study was to evaluate the effect of compaction levels on soil bulk density, porosity and penetration resistance, as well as the consequences on root growth, leaf area index and yield of common bean and wheat in crop succession. The treatments were: NT – continuous no-till for six years; NTc – NT with additional compaction; Chi – chisel plow […]
Assessment of biodiversity in rhizobia symbionts of common bean (Phaseolus vulgaris L.) in Santa Catarina, Brazil
01/Jun/2008
Brazilian soils usually present a great number of populations of rhizobial bacteria capable of nodulating and fixing N2 in symbiosis with common bean (Phaseolus vulgaris L.), but the diversity of these bacteria is still poorly known. This study aimed to assess the biodiversity of micro-symbionts of common bean in the state of Santa Catarina in southern Brazil. One-hundred and seventeen isolates were obtained from field-grown plants in 23 areas of the far west, midwest and southern plateau of Santa Catarina. […]
Nitrogen sources and doses for common bean in succession to grasses under no-tillage
01/Dec/2007
Nitrogen is an essential nutrient for common bean. However, there are still doubts about which source and level should be used to supply crops with this nutrient via sidedressing application in no-tillage systems. The objective of this work was to evaluate the influence of sources and doses of sidedressed nitrogen on common bean nutrition and grain yield (Phaseolus vulgaris L.) under no-tillage, on a Rhodic Nitisol. It was used a randomized complete block design with four replications, in a 2×4 […]
Decomposition and release of nitrogen, phosphorus and potassium from residues of common bean crop
01/Aug/2007
The objective of this study was to measure the speed of decomposition and nutrient release in situ from residues of common bean (Phaseolus vulgaris L.) crop. In field conditions, leaves of common bean cultivars senesced during the growth cycle and stems and podwalls after pod threshing were collected. These residues contained 2.3 Mg ha-1 of mass, 31 kg ha-1 of N and 2.4 kg ha-1 of P that corresponded to 63, 41 and 28 % of total mass, N and […]
Leaf senescence of common bean plants as affected by soil phosphorus supply
01/Jun/2007
Responses of leaf senescence to P supply could constitute adaptive mechanisms for plant growth under P-limiting conditions. The aim of this study was to evaluate the effects of soil P supply on leaf senescence of common bean (Phaseolus vulgaris L.). Eight P levels, ranging from 5 to 640 mg kg-1 P, were applied to pots containing four bean plants of cultivar Carioca in 10 kg of an Oxic Haplustult soil. Attached leaves were counted weekly, abscised leaves were collected every […]
Agronomic efficiency of selected rhizobia strains and diversity of native nodulating populations in Perdões (MG – Brazil). II – beans
01/Oct/2006
Common bean (Phaseolus vulgaris L.) is an economically and socially highly relevant staple food and an excellent protein source for the Brazilian population. Symbiosis of beans and N2 fixing bacteria can increase yields and decrease yield costs. The first aim of this study was to evaluate the agronomic efficiency of previously selected rhizobia strains compared to the recommended strain (CIAT 899). Phenotypic diversity of rhizobia native populations was evaluated by cultural characteristics and analysis of total protein profiles by polyacrilamide gel […]
Absorption and use of phosphorus by soybean and common bean crops and by weeds
01/Dec/2005
This work aimed to evaluate the absorption and use of phosphorus (P) by soybean and common bean crops and by weeds. The experiment was carried out in a greenhouse from August to November 2002. I was adopted a randomized block design with three replications, in a 6 x 4 factorial scheme. Six vegetal species (soybean (Glycine max), common bean (Phaseolus vulgaris), two Euphorbia heterophylla biotypes (susceptible and resistant to ALS inhibitor herbicides), Bidens pilosa and Desmodium tortuosum) and four doses of P […]
Common bean response to variable proportions of calcium and magnesium in the cation exchange capacity of oxisols
01/Oct/2003
A greenhouse experiment was carried out to evaluate the effect of the Ca/Mg ratio in the cation exchange capacity on common bean growth. Samples of a typic ferric aluminum Red Latosol (LVat) and a psamitic dystrophic Red Latosol (LVdp), both Haplortox (U.S. Soil Taxonomy) in pots containing 3.5 dm3 of soil were treated with Ca:Mg ratios of 1/2, 1, 2, 4, 6 and 8. The experiment was arranged in a completely randomized block design with six replications. Three replications were harvested […]