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- Enhancing growth, nutrient uptake and flowering of Tagetes patula plants through the application of suspensions of Chlorella vulgarisPublication . Vieira, João; Saque, Moisés; Viana, Catarina; Rodrigues, Maria Helena; Guerreiro David Coelho, Luísa Isabel; Gama, Florinda; Varela, João; Pereira, Hugo; Reis, Mário; Pestana, Maribela; Correia, Pedro JoséTagetes patula L. is a prominent plant that is frequently used for its ornamental value. Marigolds are sources of various compounds of great interest to agricultural, pharmaceutical, and nutritional industries. Microalgae can be applied as a biostimulant as they have multifunctional properties in agriculture, namely facilitating nutrient uptake, improving crop performance and physiological status, and thus increasing tolerance to abiotic stress. This study evaluated the efect of applying Chlorella vulgaris as a plant biostimulant on the growth and fowering of T. patula plants. Microalgae suspensions were applied to the substrate at concentrations of 0.5, 2.0 and 5.0 g dry weight (DW) L−1. A set of plants without the application of microalgae was used as control. The use of microalgae had a positive impact on plant growth. Specifcally, C. vulgaris application resulted in greater height, while the highest concentration (5.0 g DW L−1) resulted in higher fresh weight. Microalgae application signifcantly promoted the earlier fowering of marigolds. The macronutrient and micronutrient values were statistically similar between the control plants and those treated with microalgae. When considering only the treated plants, there was a signifcant correlation between the concentration of C. vulgaris and the concentrations of N, P, Mn and Cu in the shoots of T. patula plants. Plants receiving higher concentrations of C. vulgaris exhibited higher levels of these nutrients. These results highlight the potential use of Chlorella vulgaris as an efective biostimulant for enhancing the growth, fowering, and nutrient uptake of T. patula, ofering valuable applications for improving ornamental plant production and, ultimately, agricultural sustainability.
- Evaluation of Chlorella vulgaris application as a biostimulant for lettuce growth in soilless culturePublication . Vieira, João; Saque, Moisés; Gama, Florinda; Viana, Catarina; Guerreiro David Coelho, Luísa Isabel; Rodrigues, Maria Helena; Varela, João; Pereira, Hugo; Palencia, Pedro; Reis, Mário; Pestana, Maribela; Correia, Pedro JoséThis study evaluated the effect of Chlorella vulgaris application on the growth of soilless-grown lettuce (Lactuca sativa cv. 'Oreja de Mulo') cultivated outdoors. Microalgae suspensions were applied weekly at concentrations of 0.5, 2.0, and 5.0 g L(-)1. Plants grown without the application of microalgae were used as the control. Leaf chlorophyll concentration was registered at the beginning and at the end of the experiment, and biomass parameters were assessed at harvest. Compared with control, the highest concentration of C. vulgaris (CV5) exhibited the maximum increase in leaf area (67.4%), root fresh weight (138.7%), root volume (92.1%) and root dry weight (150.0%). This concentration further promoted higher accumulation of nitrogen (44.9%), phosphorus (96.4%), potassium (59.5%), and iron (Fe) (43.8%) in aerial parts of the lettuce plants These findings demonstrate the potential of C. vulgaris suspensions as effective biostimulants for improving growth, nutrient uptake, and biomass accumulation in hydroponic lettuce production, supporting more sustainable agricultural practices.
- The conversion of rockrose (Cistus ladanifer L.) shrubland into biodiverse pasturesPublication . Vieira, João; Filip, Iván Daniel; Soares Curado de Matos, Isabel Cristina; Rodrigues, Alessandra; Trindade, Ana Rita; Silva, Luís; Cassinello, João; Carita, Teresa; Ferreira da Silva da Costa Freitas, Maria de Belém; Neves, Maria AlcindaPastures in the Mediterranean region are vital for sustaining local agriculture and preserving biodiversity. When well-managed, these pastures enhance soil structure and fertility, reduce erosion, and improve water retention. These functions are especially critical in a climate marked by hot, dry summers and mild, wet winters. Moreover, these systems play a key role in carbon sequestration, contributing significantly to climate change mitigation. Mediterranean pastures also support the conservation of endemic plant species and provide essential habitats for a variety of wildlife. Quinta do Freixo (Algarve, Portugal) with an area around 800 hectares, is dedicated to sustainable agriculture and promotes ecological, economic and social sustainability. In addition to organic agriculture production, the farm also produces value-added food products and offers rural tourism experiences. On this farm, a dense shrubland of rockrose (Cistus ladanifer L.) is converted into pastures using a holistic method that includes mechanical cutting of the shrubs, spreading hay an regenerative rotational grazing (RRG) system. As a part of the project -C05-i03-I000237), these restored pastures are regularly monitored. Assessments included measurements of dry matter production and floristic composition. In addition, both the pastures and Cistus ladanifer shrublands were evaluated for the nutritional value and mineral composition of their foliage material. This approach has contributed to the development of species-rich pastures, rich in legumes and grasses and characterized by high protein content, excellent digestibility, and a well-balanced mineral composition. Although Cistus ladanifer had a relatively lower nutritional value due to its lower protein content and digestibility, the analysis showed that its aerial parts can serve as a supplementary feed resource, especially in periods of forage scarcity, contributing to overall feed availability in extensive grazing systems.The control of shrublands through this practice maintains biodiversity and reduces the risk of wildfires by effectively managing fuel loads.