480 documents found, page 1 of 48
Effect of Foliar Application of Nitrogen-Fixing Microorganisms and Algae Extrac...
Arrobas, Margarida; Roque, João; Martins, Sandra; Brito, Cátia; Correia, Carlos Manuel; Rodrigues, ManuelThis study presents the results of two on-farm trials evaluating the efficacy of a nitrogen (N)-fixing inoculant (Methylobacterium symbioticum) applied as a foliar spray to provide N to hazelnut (Corylus avellana L.) and walnut (Juglans regia L.) trees. In the hazelnut trial, a factorial design was employed with soil N application at three levels [0 (N0), 40 (N40), and 80 (N80) kg ha−1] and foliar application o...
A Spray Foliar Containing Methylobacterium symbioticum Did Not Increase Nitroge...
Rodrigues, Manuel Ângelo; Lopes, João Ilídio; Martins, Sandra; Brito, Cátia; Correia, Carlos Manuel; Arrobas, Margarida; Rodrigues, ManuelBiological nitrogen (N) fixation has been advocated in agricultural fields due to being considered a more sustainable way to introduce N into agrosystems than industrial N fertilizers. In this study, a foliar spray inoculant containing the microorganism Methylobacterium symbioticum was applied. This microorganism is known for fixing N in the phyllosphere, regardless of the cultivated species. This study was con...
Sewage sludge showed high agronomic value, releasing nitrogen faster than farmy...
Dimande, Paulo; Arrobas, Margarida; Correia, Carlos Manuel; Rodrigues, ManuelThe use of fertilizers in agriculture, particularly organic fertilizers such as sewage sludge, is a key research priority due to its impacts on crop productivity, production costs, environmental risks and the push for a more circular economy. This study, conducted in Bragan & ccedil;a, northeastern Portugal, focused on forage maize during the 2022 and 2023 growing seasons. Eight fertilization treatments were es...
Biomass and nutrient release dynamics of decomposing rolling down legume cover ...
Brito, Cátia; Martins, Sandra; Saraiva, Francisco; Roque, João; Arrobas, Margarida; Rodrigues, Manuel Ângelo; Correia, CarlosWell-managed cover crops are gaining traction as an alternative to conventional tillage, offering a range of agronomic and ecological benefits. This field study, conducted in a commercial vineyard in the Douro region (Portugal) during the 2022/2023 growing season, evaluated the decomposition dynamics and nutrient release from different legume cover crop residues over a period of 183 days after sowing and 114 da...
Regenerative Agriculture: Insights and Challenges in Farmer Adoption
Moisés, Cristiano; Arrobas, Margarida; Tsitos, Dimitrios; Pinho, Diogo; Rezende, Raiza Figueiredo; Rodrigues, Manuel ÂngeloRegenerative agriculture has emerged as a new organic farming movement, initially difficult to distinguish from similar approaches. Its core concerns, such as ecosystem degradation caused by intensive farming, align with those of many other organic systems. However, regenerative agriculture prioritizes soil health, biodiversity, and social equity, setting itself apart through its scalability and flexibility. Un...
White Lupin and Hairy Vetch as Green Manures: Impacts on Yield and Nutrient Cyc...
Raimundo, Soraia; Arrobas, Margarida; Ribeiro, António C.; Rodrigues, Manuel ÂngeloOrganic farming systems, which prohibit synthetic fertilizers, often rely on legumes for their ability to fix atmospheric nitrogen (N). In orchards, legumes can be established as cover crops between tree rows to enhance nutrient cycling. This study evaluated the effects of two legume cover crops, white lupin (Lupinus albus L.) and hairy vetch (Vicia villosa Roth), compared to a Control treatment with convention...
Increased uptake and accumulation of phosphorus and other nutrients by legumes ...
Aguiar, Peltier; Arrobas, Margarida; Rodrigues, Manuel ÂngeloLegumes are promoted in agroecosystems for their ability to fix atmospheric nitrogen (N), thereby reducing or eliminating the need for N fertilisation while also contributing N-rich organic residues, which non-legume species can subsequently utilise. In phosphorus (P)-poor soils, certain legumes appear to access less available forms of P, converting them into organic P and facilitating its use by non-legume spe...
Sewage Sludge Provided Nitrogen To Maize (Zea Mays L.) Very Rapidly, Demonstrat...
Dimande, Paulo; Arrobas, Margarida; Rodrigues, Manuel ÂngeloThis study aims to evaluate the potential of sewage sludge as a sustainable alternative to traditional farmyard manures, considering the limited availability of such resources in many regions specializing in crop production. This study compared the application of sewage sludge (SS) and cow manure (CM) at equivalent nitrogen (N) rates in silage maize (Zea mays L.) cultivation over two growing seasons. Organic am...
The Composting of Water Hyacinth: A Life Cycle Assessment Perspective
Serafini, Lais Fabiana; Arrobas, Margarida; Rodrigues, Manuel Ângelo; Feliciano, Manuel; Miguens, Filomena; Oliveira, Verónica; Santos, DanielaWater hyacinth is an invasive species that causes eutrophication in lentic waters. While mechanical removal is effective, it generates hazardous waste with biological contamination risk. Composting is a safe waste treatment option, inhibiting seeds and yielding agriculturally suitable compost. Life cycle assessment evaluated the environmental impacts of six composting piles using eight different by-products (po...
Methylobacterium symbioticum Applied as a Foliar Inoculant Was Little Effective...
Arrobas, Margarida; Correia, Carlos M.; Rodrigues, M.A.Nitrogen (N) is a limiting ecological factor for plant growth in most agroecosystems. Biological N fixation, especially from nodulated legumes, has been promoted in recent decades as an alternative or complement to industrially synthesized N fertilizers. The possibility of utilizing N-fixing organisms from the phyllosphere that demonstrate effectiveness across a wide range of crops is particularly exciting. In ...