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- Structure and floristic composition associated with an endangered species Beta patula Aiton (Amaranthaceae) in the Islands of Madeira ArchipelagoPublication . Nóbrega, Humberto; Freitas, Gregório; Zavattieri, M. A.; Ragonezi, Carla; Carvalho, Miguel Â. A. Pinheiro deTwenty-two native Crop Wild Relatives (CWR) occur in specific dry environments of Madeira Archipelago, like Desembarcadouro islet in Ponta de São Lourenço and Chão islet in Desertas Islands. Nine of them share the same gene pool with crop species included in Annex I of the International Treaty on Plant Genetic Resources for Food and Agriculture. Amongst them, Beta patula Aiton, an IUCN Critically Endangered species, has been studied in detail for in situ and ex situ conservation. The present paper summarises the information recorded during the Beta patula population assessment. Valuable information on plant communities associated with this species was obtained.
- Monitoring system and in situ conservation of endemic and threatened Beta patula Aiton populations in Madeira RegionPublication . Nóbrega, H.; Freitas, G.; Zavattieri, M. A.; Ragonezi, C.; Frese, L.; Carvalho, M. A. A. Pinheiro det Madeira Archipelago is a hotspot for crop wild relatives (CWR) of crop cultures. Some of these CWR are present in very specific environments, such as, in Ponta de Sa˜o Lourenc¸o or Desertas Islands. One such species is Beta patula Aiton, a Critically Endan gered species which belongs to the Gene Pool 1b of cultivated beets. A continuous effort has been devel oped for its ex situ conservation through the storage of accessions (ISOP2512 and ISOP1911) in the ISO Plexis GeneBank at the University of Madeira Simultaneously, a series of studies have been carried out to understand the species’ ecogeographic and ecological requirements, to validate populations’ boundaries and sizes, and to establish population dynamics. This study includes a complete floristic survey at the B. patula locations of, Desembar cadouro islet (DI) with 12 (DI1–DI12) sampling sites, and Cha˜o islet (CI) with 3 (CI1–CI3). Several Biodiversity indices were calculated for these loca tions. Plot DI3 exhibited the highest values for Corrected Evenness (E0 = 0.77 ± 0.07), Shannon– Weaver Diversity Index (H0 = 2.48 ± 0.12), and Hill’s Index (N2 = 4.47 ± 0.72), with a total sum of 306 individuals of B. patula. The demographic status of B. patula populations in DI and CI was determined yearly between 2014 and 2018. The results show an average population size of 16,906 and 2917 plants, respectively. These data will be used for the estab lishment of a protocol to monitor and manage a genetic reserve for B. patula and other CWR. By doing so, our work will contribute to the implemen tation of the European genetic reserve network.
- Prospeção e caracterização dos recursos genéticos de macieira, Malus domestica Borkh, na MadeiraPublication . Gouveia, Carla S.S.; Ascarini, Fabio; Nóbrega, Humberto G. M. de; Freitas, José G. R. de; Carvalho, Miguel Â. A. Pinheiro deA Madeira possui condições agroecológicas únicas, que permitem o desenvolvimento de grande diversidade de espécies frutícolas. A macieira é uma fruteira tradicional na Madeira que se distribui pelas suas freguesias montanhosas, desde o Oeste, Achadas da Cruz, até o Este, Faial. O cultivo da macieira desenvolve-se em pequenos pomares, que albergam uma diversidade de cultivares, cuja produção é consumida em fresco ou utilizada na produção de sidra. A prospeção e inventariação dos recursos genéticos desta fruteira procura aprofundar os conhecimentos sobre a sua diversidade, tendo resultado no registo de 10 variedades de conservação no Catálogo Nacional de Variedades, entre as quais o Pero Domingos, a Maçã Barral, a Maçã Cara de Dama e o Pero Calhau. Os dados desta inventariação são disponibilizados, através das plataformas GRIN-Global e GBIF. Está em curso um projeto que visa a valorização destas variedades locais, através da sua caracterização morfo-agronómica e nutricional. O presente trabalho apresenta os resultados preliminares da caracterização morfométrica de 4 dessas variedades. Os parâmetros utilizados incluem o hábito de crescimento, época de floração, frutificação e colheita, e 10 caracteres morfológicos do fruto. Os resultados obtidos permitem-nos inferir que as 4 variedades são distintas entre si e apresentam características agronómicas que lhes conferem valor comercial. Adicionalmente, o fruto do Pero Domingos foi analisado em relação a 5 parâmetros nutricionais e físico-químicos, e à sua aptidão para consumo em fresco ou processado (desidratado, compotas, sidra). O Pero Domingos apresentou um bom tempo de conservação no pós-colheita. No entanto, recomenda-se o seu uso na produção de sidra ou confeção de compotas até 1 semana de pós-colheita. O teor de sólidos solúveis variou significativamente nas compotas. O pH da sidra diminuiu significativamente com a profundidade da coluna na pipa.
- Phenotypic flexibility and drought avoidance in taro (Colocasia esculenta (L.) Schott)Publication . Gouveia, Carla S. S.; Ganança, José F. T.; Nóbrega, Humberto G. M.; Freitas, José G. R. de; Lebot, Vincent; Carvalho, Miguel Â. A. Pinheiro deTaro (Colocasia esculenta (L.) Schott) is a substantial staple food in most of the tropical regions. Prolonged exposure to drought impairs crop production worldwide. Tolerant crops have the best capability to cope and avoid drought, through phenotypic flexibility mechanisms. The water use efficiency (WUE) is well known in taro crops, but very scarce information is available relating to their nutrient efficiency (NER) in drought conditions. Our work provided pertinent information about the physiological variation of seven taro accessions subjected to seven months of drought, by recording the differences for nutrient allocation, chlorophyll canopy, biomass loss, and stress intensity. Significant relationships between control and drought treatments on WUE (+85%), total plant biomass (TPB, -26.8%), chlorophyll content index (CCI, +1.8%), and nutrient harvest index (NHI, +0.2%) were detected. Drought led to a generalized loss of TPB as drought avoidance strategy, although distinct phenotypic flexibility was observed through the root: shoot ratio (R:S) and stress index (SI) from the corm and shoot organs. The nutrient allocation from the corms to shoots, with NER increase registered in drought conditions, can be a valuable tool to complement the TPB and WUE productivity traits, to be used in taro breeding programs.
- Screening of elite and local taro (Colocasia esculenta) cultivars for drought tolerancePublication . Ganança, José Filipe T.; Freitas, José Gregório F.; Nóbrega, Humberto Gil M.; Rodrigues, Vanessa; Antunes, Gonçalo; Rodrigues, Miguel; Carvalho, Miguel Ângelo A. Pinheiro de; Lebot, VincentTaro (Colocasia esculenta (L.) Schott) is a vegetative propagated tropical root occupying the 9th position among world food crops. Taro is an important staple food for many local populations of Asia and Africa. The crop is dependent of wet and highly irrigated growth conditions. Under the scenario of undergoing climatic changes, is estimated that taro production could decrease in the next 30 years as result of drought constraints. The project EU Aid Taro, DCI-Food/2009/45 “adapting propagated crops to climatic and commercial changes” aims to study ways to adapt this clonally propagated root to these climatic changes. A set of drought stress assays were realized at ISOPlexis Genebank (Madeira University), using local taro cultivars (Macaronesian taro genepool) and elite cultivars and seedlings provided by the Secretariat of the Pacific Community (SPC). The 1st pilot assay was realized in a small greenhouse, included 3 local cultivars and aimed to modelate the wattering regimes and their influence on crop growth. The 2nd full assay was realized in two greenhouses, during a full plant growth cycle. Thirty four taro cultivars, 15 elite lines provided by SPC, and 19 local cultivars, from Madeira (10), Canary Islands (6), Azores (2), and Cyprus (1) were screened. Plants were individually cultivated in pots under 2 contrasting wattering regimes, high (0,36 liters/day) and low (0,18 liters/day ). Data for 14 morpho-agronomic traits, biomass and yield parameters were collected from 5 plants for each cultivar, per treatment.
- Estimation of Productivity and Above-Ground Biomass for Corn (Zea mays) via Vegetation Indices in Madeira IslandPublication . Macedo, Fabrício Lopes; Nóbrega, Humberto; Freitas, José G. R. de; Ragonezi, Carla; Pinto, Lino; Rosa, Joana; Carvalho, Miguel A. A. PinheiroThe advancement of technology associated with the field, especially the use of unmanned aerial vehicles (UAV) coupled with multispectral cameras, allows us to monitor the condition of crops in real time and contribute to the field of machine learning. The objective of this study was to estimate both productivity and above-ground biomass (AGB) for the corn crop by applying different vegetation indices (VIs) via high-resolution aerial imagery. Among the indices tested, strong correlations were obtained between productivity and the normalized difference vegetation index (NDVI) with a significance level of p < 0.05 (0.719), as well as for the normalized difference red edge (NDRE), or green normalized difference vegetation index (GNDVI) with crop productivity (p < 0.01), respectively 0.809 and 0.859. The AGB results align with those obtained previously; GNDVI and NDRE showed high correlations, but now with a significance level of p < 0.05 (0.758 and 0.695). Both GNDVI and NDRE indices showed coefficients of determination for productivity and AGB estimation with 0.738 and 0.654, and 0.701 and 0.632, respectively. The use of the GNDVI and NDRE indices shows excellent results for estimating productivity as well as AGB for the corn crop, both at the spatial and numerical levels. The possibility of predicting crop productivity is an essential tool for producers, since it allows them to make timely decisions to correct any deficit present in their agricultural plots, and further contributes to AI integration for drone digital optimization.
- Assessing the diversity of sea beet (Beta vulgaris L. ssp. maritima) populationsPublication . Ascarini, F.; Nóbrega, H. G.M.; Leite, I. S.; Freitas, G.; Ragonezi, C.; Zavattieri, M. Amely; Carvalho, M. A. A. Pinheiro deBeta vulgaris L. subsp. maritima (L.) Arcang., sea beet, is a morphologically and genetically variable species, belonging to beet primary gene -pool. This crop wild relative is a valuable genetic resource for resistance improvement in beets and could play an important role in crop yield sustainability. Eleven Madeiran sea beet populations were characterized using morphological descriptors and genetic markers. Our goal was to evaluate these populations as a potential source of valuable genetic material. Morphological characterization showed a high quantitative variation among populations. Plant height and inflorescence height parameters had the highest influence in the separation of populations. Molecular analysis was performed with polymorphic SSRs to determine genetic variability between populations. Both PCA and PCoA revealed three clusters that separated the populations according to morphological and genetic traits, respectively. This study contributes to the knowledge of sea beet diversity in Madeira’s archipelago and to the perception that the islands' specific environmental conditions influence its genetic variability, making these populations a possible gene source for sugar beet breeding programs
- 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.