Browsing by Author "Carvalho, Miguel Â. A. Pinheiro de"
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- Abscisic acid phytohormone estimation in tubers and shoots of Ipomoea batatas subjected to long drought stress using competitive immunological assayPublication . Gouveia, Carla S. S.; Ganança, José F. T.; Slaski, Jan J.; Lebot, Vincent; Carvalho, Miguel Â. A. Pinheiro deSweet potato (Ipomoea batatas L.), typically cultivated in temperate climates under low inputs, is one of the most important crops worldwide. Abscisic acid (ABA) is an important plant stress-induced phytohormone. Hitherto, few works analyzed the ABA function in sweet potato tissue growth. Very scarce information is available concerning the ABA role in sweet potato response to water scarcity conditions. Here, we show the ABA content var iation in shoots and tubers of eight sweet potato accessions subjected to drought stress. ABA was also related to other resistance traits, such as chlo rophyll content index (CCI), carbon isotopic discrimination (Δ13C), oxalic acid (OA) and water use efficiency (WUE), to assess stress response mecha nisms to water deficit between their organs. The most resilient drought stressed sweet potato plants accumulated ABA-shoot, and significantly decreased the ABA-tuber content. ABA signaling was related to Δ13C and CCI decrease and WUE increment, as an attempt to cope with water stress by partially closing the stomata. The partial closure of stomata could be in part due to the presence of OA-shoots, known to affect the intensity of the ABA-shoot signal in stomatal closure. Higher CCI content and minimal Δ13C-shoot differences indicated good carboxylation fractionation, with higher Δ13C-tuber content as an indicator of efficient tuber 13C fixation and growth. Our work demonstrated that ABA could be used in conjunction with the other traits studied for the assessment of sweet potato whole-plant responses to environmental stresses, and thus aid the selection of the best drought tolerant genotypes for breeding programs.
- Adapting Agriculture to Climate Change: A Synopsis of Coordinated National Crop Wild Relative Seed Collecting Programs across Five ContinentsPublication . Eastwood, Ruth J.; Tambam, Beri B.; Aboagye, Lawrence M.; Akparov, Zeynal I.; Aladele, Sunday E.; Allen, Richard; Amri, Ahmed; Anglin, Noelle L.; Araya, Rodolfo; Arrieta-Espinoza, Griselda; Asgerov, Aydin; Awang, Khadijah; Awas, Tesfaye; Barata, Ana Maria; Boateng, Samuel Kwasi; Magos Brehm, Joana; Breidy, Joelle; Breman, Elinor; Brenes Angulo, Arturo; Burle, Marília L.; Castañeda-Álvarez, Nora P.; Casimiro, Pedro; Chaves, Néstor F.; Clemente, Adelaide S.; Cockel, Christopher P.; Davey, Alexandra; De la Rosa, Lucía; Debouck, Daniel G.; Dempewolf, Hannes; Dokmak, Hiba; Ellis, David; Faruk, Aisyah; Freitas, Cátia; Galstyan, Sona; García, Rosa M.; Ghimire, Krishna H.; Guarino, Luigi; Harker, Ruth; Hope, Roberta; Humphries, Alan W.; Jamora, Nelissa; Jatoi, Shakeel Ahmad; Khutsishvili, Manana; Kikodze, David; Kyratzis, Angelos C.; León-Lobos, Pedro; Liu, Udayangani; Mainali, Ram P.; Mammadov, Afig T.; Manrique-Carpintero, Norma C.; Manzella, Daniele; Mat Ali, Mohd Shukri; Medeiros, Marcelo B.; Mérida Guzmán, María A.; Mikatadze-Pantsulaia, Tsira; Mohamed, El Tahir Ibrahim; Monteros-Altamirano, Álvaro; Morales, Aura; Müller, Jonas V.; Mulumba, John W.; Nersesyan, Anush; Nóbrega, Humberto G.M.; Nyamongo, Desterio O.; Obreza, Matija; Okere, Anthony U.; Orsenigo, Simone; Ortega-Klose, Fernando; Papikyan, Astghik; Pearce, Timothy R.; Carvalho, Miguel Â. A. Pinheiro de; Prohens, Jaime; Rossi, Graziano; Salas, Alberto; Singh Shrestha, Deepa; Siddiqui, Sadar Uddin; Smith, Paul P.; Sotomayor, Diego A.; Tacán, Marcelo; Tapia, César; Toledo, Álvaro; Toll, Jane; Vu, Dang Toan; Vu, Tuong Dang; Way, Michael J.; Yazbek, Mariana; Zorrilla, Cinthya; Kilian, BenjaminThe Adapting Agriculture to Climate Change Project set out to improve the diversity, quantity, and accessibility of germplasm collections of crop wild relatives (CWR). Between 2013 and 2018, partners in 25 countries, heirs to the globetrotting legacy of Nikolai Vavilov, undertook seed collecting expeditions targeting CWR of 28 crops of global significance for agriculture. Here, we describe the implementation of the 25 national collecting programs and present the key results. A total of 4587 unique seed samples from at least 355 CWR taxa were collected, conserved ex situ, safety duplicated in national and international genebanks, and made available through the Multilateral System (MLS) of the International Treaty on Plant Genetic Resources for Food and Agriculture (Plant Treaty). Collections of CWR were made for all 28 targeted crops. Potato and eggplant were the most collected genepools, although the greatest number of primary genepool collections were made for rice. Overall, alfalfa, Bambara groundnut, grass pea and wheat were the genepools for which targets were best achieved. Several of the newly collected samples have already been used in pre-breeding programs to adapt crops to future challenges.
- Anticipating the Climate Change Impacts on Madeira’s Agriculture: The Characterization and Monitoring of a Vine AgrosystemPublication . Carvalho, Miguel Â. A. Pinheiro de; Ragonezi, Carla; Oliveira, Maria Cristina O.; Reis, Fábio; Macedo, Fabrício Lopes; Freitas, José G. R. de; Nóbrega, Humberto; Ganança, José Filipe T.Climate—Madeira Strategy (CMS) foresees two models to describe the climate scenarios for the Madeira region in 2050 and 2070. These scenarios anticipate an average temperature rise of 1.4 to 3.7 ◦C and a decrease in precipitation by 30 to 40%. Consequently, Madeira’s agriculture will suffer the impacts of climate change. To understand these impacts, a baseline of major agrosystem components needs to be established, with the ultimate goal to monitor its consequences in its functioning. CASBio project used the 1961–1991 and 2010–2020 meteorological data series to modulate climate conditions and characterize and monitor six agrosystems for 2 years. One of them was a vineyard, Quinta das Vinhas, representing a typical agrosystem in the Mediterranean climate. The annual and seasonal variation in climatic parameters, soil conditions, microbiological communities, floristic and insect diversity, and crop production was assessed, using a total of 50 parameters. The results were used to establish a baseline of the agrosystem components and their seasonal and annual variation. The major findings are: (i) winter and summer extreme events show a trend in temperature and precipitation supporting a fast change in climate; (ii) a critical imbalance between nitrogen fixing and denitrifying bacteria was identified, especially in summer, that could be determined by the rise in temperature and drought; (iii) among floristic diversity, the therophytes and geophytes confirm to be the most suitable indicators for the rise in temperature and reduction in precipitation in the agrosystems; (iv) an imbalance in favor of C. capitata plague was observed, associated with the summer rise in temperature and decrease in precipitation; (v) despite an increase in most of the grape varieties production, the Madeiran wine local varieties were shown to be less stable in productivity under observed climate conditions. The agrosystem baseline is a starting point for long term monitoring and allows for further quantifying the influence of climate change on agrosystem productivity, resilience, and sustainability.
- Biochemical study of attached macroalgae from the Madeira Archipelago and beach-cast macroalgae from the Canary Islands: multivariate analysis to determine bioresource potentialPublication . Nunes, Nuno; Valente, Sofia; Ferraz, Sónia; Barreto, Maria Carmo; Carvalho, Miguel Â. A. Pinheiro deFifteen attached macroalgae from the Madeira Archipelago, comprising three green, three red and nine brown algal species, as well as two beach-cast macroalgal samples, collected along the north shore of Gran Canaria, were assessed for their biochemical properties. The anal ysis included the determination of total minerals, total carbohydrates, protein, lipids, chlorophyll a, total carote noids, total phenolic content, fucoxanthin and phycobilins (allophycocyanin, phycocyanin and phycoerythrin). The results showed a high variability of biochemical composi tion, allowing for the targetting of specific bioresources for particular purposes, including functional foods. This work provides the foundation for a biorefinery strategy implementation plan, for which specific macroalgae may be tar geted for valuable and beneficial compounds
- Citrate and isocitrate in plant metabolismPublication . Popova, Tatyana N.; Carvalho, Miguel Â. A. Pinheiro deThe relevance of citrate and isocitrate metabolism in plants is discussed in connection with the different pathways for their conversions. The routes for citrate and isocitrate conversions are incorporated into the system of cross-linked metabolic processes and may provide carbon skeletons for nitrogen assimilation and reducing equivalents for biosynthetic reactions, support the functioning of the glyoxylate cycle and play an important role in the TCA and energy metabolism as a whole. The possibility of the coupling of citrate and isocitrate metabolism with various electron transport systems is discussed from the point of view of the efficiency of the balancing cellular NAD P H Ž . Ž . rNAD P and ATP q rADP ratios. The role of citrate and isocitrate and their derivations as potent effectors of some enzymes is considered. Special attention is paid to the enzymes associated with citrate and isocitrate metabolism and to the mechanisms which regulate their activity. The possibilities of the coordination of the main processes of energy and biosynthetic metabolism at the level of citrate and isocitrate distribution are discussed.
- Cytometric determination of genome size in Ruscus (Liliaceae) from the flora of MadeiraPublication . Carvalho, Miguel Â. A. Pinheiro de; Lucas, Iolanda C. Vale; Nieves Redondo, M. de las; Horjales, Marina
- Distribution of Genetic Diversity in Beta patula Aiton Populations from Madeira Archipelago, PortugalPublication . Ragonezi, Carla; Nóbrega, Humberto; Leite, Maria Inês; Freitas, José G. R. de; Macedo, Fabrício Lopes; Carvalho, Miguel Â. A. Pinheiro deBeta patula Aiton is a crop wild relative (CWR) which belongs to the Gene Pool 1b and is considered a Critically Endangered species, and is present in very specific environments, such as the Desembarcadouro islet (DI) in Ponta de São Lourenço or Chão islet (CI) in the Desertas Islands. The ISOPlexis Center (University of Madeira) has been providing continuous support for its in situ conservation by keeping a management plan of wild populations and an ex situ conservation strategy through the storage of accessions in the ISOPlexis GeneBank. The present work intends to present the spatial distribution of genetic variability and diversity in these B. patula populations using eight polymorphic Simple Sequence Repeat (SSR) markers. The overall results lead to the identification of three spots with a high genetic diversity. CI with a small cluster of individuals shows a genetic footprint different from DI, having unique alleles present in its population. DI has two distinct areas: the western area, with a higher individual density but with a lower genetic diversity and higher allele fixation; and the central area, with a lower individual count but with a higher genetic diversity and with the presence of unique alleles. Despite some genetic differences, the comparison of the two islets’ DI and CI populations shows that they have more similarities than differences. Analysis of the Molecular Variance, based on the hierarchical cluster, showed a 9% diversity between populations, 68% among individuals, and 23% within individuals. This data will be used for the establishment of a protocol to monitor and manage B. patula genetic diversity under a genetic reserve, subsequently contributing to the European Genetic Reserve network implementation and the protection of this important CWR.
- Drought avoidance and phenotypic flexibility of sweet potato (Ipomoea batatas (L.) Lam.) under water scarcity conditionsPublication . Gouveia, Carla S. S.; Ganança, José F. T.; Nóbrega, Humberto G. M.; Freitas, José G. R.; Lebot, Vincent; Carvalho, Miguel Â. A. Pinheiro deSweet potato (Ipomoea batatas (L.) Lam.) is an important staple food in several regions of the world. Water scarcity is the most devastating abiotic stress, with a great impact on crop productivity, food security, and subsistence. Drought restricts the nutrient intake and transport into the plant. Tolerant crops have morphological mechanisms of drought avoidance and/or phenotypic flexibility, showing also good water and nutrient efficiency. However, that information is scarce for sweet potato, which is usually based on physiological traits of plant productivity. Here, we show the physiological responses of eight sweet potato accessions subjected to a 3 months’ drought period, by recording their differences for nutrient and leaf chlorophyll content, biomass and stress level. Our results showed that the differences in water use efficiency (WUE, +68.1%), chlorophyll content index (CCI, -5.3%), total plant biomass (TPB, -55.4%), nutrient efficiency (NER, +38.1%) and nutrient harvest index (NHI, +2.9%) where significantly correlated with the water regime. The water shortage led to a drought avoidance response, with TPB loss in all accessions. Distinct phenotypic flexibility responses were also recorded and explained by the root:shoot ratio (R:S) and stress index (SI) variation of the storage root and shoot growth. This information could be relevant for the development of sweet potato breeding programs, adapting this crop to climate change.
- Encapsulation with Natural Polymers to Improve the Properties of Biostimulants in AgriculturePublication . Jiménez-Arias, David; Morales-Sierra, Sarai; Silva, Patrícia; Carrêlo, Henrique; Gonçalves, Adriana; Ganança, José Filipe Teixeira; Nunes, Nuno; Gouveia, Carla S. S.; Alves, Sónia; Borges, João Paulo; Carvalho, Miguel Â. A. Pinheiro deEncapsulation in agriculture today is practically focused on agrochemicals such as pes ticides, herbicides, fungicides, or fertilizers to enhance the protective or nutritive aspects of the entrapped active ingredients. However, one of the most promising and environmentally friendly technologies, biostimulants, is hardly explored in this field. Encapsulation of biostimulants could indeed be an excellent means of counteracting the problems posed by their nature: they are easily biodegradable, and most of them run off through the soil, losing most of the compounds, thus becoming inaccessible to plants. In this respect, encapsulation seems to be a practical and profitable way to increase the stability and durability of biostimulants under field conditions. This review paper aims to provide researchers working on plant biostimulants with a quick overview of how to get started with encapsulation. Here we describe different techniques and offer protocols and suggestions for introduction to polymer science to improve the properties of biostimulants for future agricultural applications.
- Evaluating the Madeiran wheat germplasm for aluminum resistance using aluminium-induced callose formation in root apices as a markerPublication . Santos, Teresa M. M. dos; laski, Jan J.; Carvalho, Miguel Â. A. Pinheiro de; Taylor, Gregory J.; Vieira, Maria R. ClementeAluminum (Al) resistance of 57 Madeiran wheat cultivars was evaluated using callose content in root tips and root elongation as markers. Al induced callose formation was a very sensitive indicator of Al damage detecting wide range of genotypic differences existing in the Madeiran wheat germplasm. A weak, yet pos i tive cor re la tion (R2=0.285, P<0.05) between callose content and root elongation was found.
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