• en
  • pt-br

All publications of “José Guilherme Marinho Guerra”

6 results

Ammonia Volatilization from Soil-Applied Organic Fertilizers

Adriano Alvim Rocha, Ednaldo da Silva Araújo ORCID logo , Silvio da Silva Santos, Jhonatan Marins Goulart, José Antonio Azevedo Espindola, José Guilherme Marinho Guerra, [...]

22/May/2019

ABSTRACT: A reliable quantification of nitrogen (N) losses by ammonia (NH3) volatilization can contribute to identifying optimized strategies of fertilizer management. The objective of this study was to quantify ammonia volatilization from several organic N sources incorporated into or applied onto the soil surface. Two cultivation areas, under snap bean and corn, were evaluated at Embrapa Agrobiology, Seropédica, Rio de Janeiro (RJ). Both experiments used a randomized complete block design in split-plots, with four replications. The main plots consisted of […]

Diversity and symbiotic capacity of bacteria isolated from nodules of two velvet bean species

Andréa Aparecida de Lima, Paulo Ivan Fernandes Júnior, Samuel Ribeiro Passos, Fernanda Santana de Paulo, Sumaya Mário Nosoline, Sérgio Miana de Faria, [...]

01/Apr/2012

Mucuna species are widely used as green manure, and little information is available about rhizobia that can nodulate them. The objective of this study was to evaluate the diversity and ability of bacteria isolated from symbiotic nodules of velvet bean (Mucuna pruriens (L.) DC.) and Mucuna deeringiana (Bort.) Merr. From the nodules of either mucuna species, grown in pots with soils from an agroecological system, 80 bacteria were isolated. The selected bacteria were classified and used to assess the symbiotic […]

Decomposition and release of nitrogen, phosphorus and potassium from residues of common bean crop

Eduardo Chagas, Adelson Paulo Araújo, Marcelo Grandi Teixeira, José Guilherme Marinho Guerra

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 […]

Improving lettuce seedling root growth and ATP hydrolysis with humates from vermicompost. I – effect of vermicompost concentration

Maria Rita Cardoso Rodda, Luciano Paqualotto Canellas, Arnoldo Rocha Façanha, Daniel Basílio Zandonadi, José Guilherme Marinho Guerra, Dejair Lopes de Almeida, [...]

01/Aug/2006

Vermicomposts present a high content of humic substances and their effects on soil properties are well-documented. However, direct effects of humic substances on plant metabolism are less known. The aim of this work was to evaluate the use of humates isolated from cattle manure vermicompost with 0.1 mol L-1 KOH on root growth and ATP metabolism of lettuce seedlings. After germination, lettuce seedlings were treated with different humate concentrations (0 to 100 mg L-1 of C) for 15 days. The root growth and the H+-ATPase […]

Improving lettuce seedling root growth and ATP hydrolysis with humates from vermicompost. II – Effect of vermicompost source

Maria Rita Cardoso Rodda, Luciano Paqualotto Canellas, Arnoldo Rocha Façanha, Daniel Basílio Zandonadi, José Guilherme Marinho Guerra, Dejair Lopes de Almeida, [...]

01/Aug/2006

Cattle manure availability is one of the most limiting factors for vermicompost production. The effects of the partial substitution of manure with sugarcane bagasse or residues of Gliricidia sepium on the quality of vermicomposts and the bioactivity of their humates were evaluated by analyzing the root growth and H+-ATPase activity of lettuce seedling roots. The substitutions of manure by sugar cane bagasse and legume cover crops residues did not affect the chemical properties of humates. Humates isolated from the different […]

Decomposition and nutrient release of perennial herbaceous legumes intercropped with banana

José Antonio Azevedo Espindola, José Guilherme Marinho Guerra, Dejair Lopes de Almeida, Marcelo Grandi Teixeira, Segundo Urquiaga

01/Apr/2006

Evaluating the decomposition of cover crop residues added to the soil allows improving the comprehension of appropriate nutrient supply for commercial crops. This study was carried out under field conditions aiming to evaluate the decomposition and nutrient release from the shoots of perennial herbaceous legumes. The treatments were green cover crops intercropped with banana: groundnut (Arachis pintoi Krapov. & W.C. Gregory.), tropical kudzu (Pueraria phaseoloides (Roxb.) Benth.), siratro (Macroptilium atropurpureum (Sessé & Moc. ex DC.) Urb.) and spontaneous vegetation (mainly […]