Caracterização morfológica e genética de cultivares de oliveiras centenárias e tradicionais para a obtenção de produtos diferenciados

As oliveiras centenárias são uma marca da paisagem Transmontana e a obtenção de azeites diferenciados destas árvores poderá ser um nicho a explorar, com vantagens económicas, sociais e ambientais. Esta estratégia só será viável após a caracterização genética das cultivares de oliveiras centenárias existentes na região. O presente trabalho teve como objetivo caracterizar morfologicamente e geneticamente, através da análise por microssatélites, cultivares de oliveiras centenárias existentes na região Transmontana. Neste estudo foram ainda incluídas cultivares tradicionais frequentemente plantadas na região de forma a elucidar possíveis relações de filogenia entre estas e as centenárias. Os resultados da análise morfológica do fruto, endocarpo e folha das oliveiras amostradas (15 tradicionais e 17 centenárias) não permitiram uma diferenciação completa das duas populações. Os caracteres mais diferenciadores nas oliveiras tradicionais estavam relacionadas com a folha e a forma do fruto, enquanto que nas centenárias estavam relacionadas com o peso e diâmetro do fruto e endocarpo. As características do endocarpo foram as que permitiram uma maior diferenciação das duas populações. Os 12 loci utilizados na análise genética permitiram detetar 74 alelos nas 32 oliveiras e evidenciaram a existência de uma grande diversidade. A população de oliveiras centenárias apresentou uma maior diversidade genética e número de alelos privados, comparativamente com a população de oliveiras novas. Em ambas as populações foi registado um excesso de heterozigóticos. Apesar do baixo valor de FST observado (0,030), a análise do structure permitiu a diferenciação das duas populações de oliveiras e sugeriu a possibilidade de algumas das oliveiras novas terem origem das centenárias. Dos loci estudados, UDO-011 e DCA18 foram os que permitiram uma maior diferenciação das duas populações podendo ser bastante úteis na certificação de oliveiras centenárias. O teste de Mantel evidenciou uma correlação positiva e altamente significativa entre os caracteres morfológicos, em especial os relacionados com o fruto, e a análise molecular. Com base nos resultados obtidos é recomendável a conservação da população de oliveiras centenárias por apresentar uma grande diversidade genética.Centenary olive trees are a typical element on Trás-os-Montes landscape, being the extraction of differentiated olive oils from these trees a potential niche to explore, with economic, social and environmental benefits. This strategy will be only feasible after the genetic characterization of the centenary olive trees of this region. This study aimed to characterize both morphologically and genetically, through microsatellite analysis, the centenary olive trees in the Trás-os-Montes region. In this study were also included traditional cultivars of this region in order to elucidate possible phylogenetic relationships between these and centenary olive trees. The results from the morphological analysis of the fruit, endocarp and leaf from the 15 traditional and 17 centenary olive trees did not allow a complete differentiation of the two populations. The most distinguishable morphological trait in traditional cultivars were related to leaf and shape of fruit, while in the centenary olive trees were most related with the weight and diameter of both the fruit and endocarp. The traits related with the endocarp were the characters that allowed a better differentiation of the two olive tree populations. The 12 loci used in the genetic analysis allowed the detection of 74 alleles in the 32 olive trees and showed a great diversity. The centenary olive trees population showed a higher genetic diversity and number of private alleles when compared to the traditional olive trees population. In both populations was observed an excess of heterozygotes. Despite the low FST value observed (0,030), the structure analysis allowed the differentiation of the two olive trees populations and indicates that some of the traditional olive tree cultivars may be originated from the centenary olive trees. Among the studied loci, UDO-011 and DCA18, allowed the greatest differentiation of the two populations and may be useful in the certification of centenary olive trees. The Mantel test showed a positive and highly significant correlation between morphological traits, especially those related to the fruit, and molecular analysis. Taking into account the results, it is suggested the conservation of the centenary olive tree population due to their higher genetic diversity.Trabalho financiado pelo Projeto "RED/AGROTEC - Red transfronteriza España Portugal de experimentación y transferencia para el desarrollo del sector agropecuario y agroindustrial" financiado no âmbito do POCTEP - Programa Cooperação Transfronteiriça Espanha-Portugal 2007-2013

Characterization of the endophytic fungal communities associated to Coleostephus myconis: looking for potential repellent/attractant compounds towards Philaenus spumarius

Philaenus spumarius is a xylem feeding insect identified so far as the only vector involved in the first European outbreak of the phytobacterium Xylella fastidiosa, affecting and devastating olive groves in Italy. One approach to reduce X. fastidiosa transmission could rely in the vector control through the use of baits to attract and/or repel de insect. Fungal endophytes inhabiting plants provide a source of candidate repellent/attractant compounds. In this work, the endophytic fungi community associated to the weed Coleostephus myconis, was studied in order to identified potential fungi that can be used as attractants or repellents of P. spumarius. Coleostephus myconis is common in olive groves and preferentially used by P. spumarius for the nymph development. Fungi were isolated from the stems, leaves and inflorescences from plants with three levels of P. spumarius infestation (i.e. no infestation, moderate and high infestation). The fungal isolates obtained were identified by sequencing the ITS region of rDNA and the partial tef1. Overall, was obtained 138 taxa belonging to 37 different genera. The endophytic community composition differs between infested and non-infested plants, solely at stems level, where the P. spumarius foam nests are present. The fungal genera, Cytospora, Diaporthe and Penicillium, which are well-known with producers of volatiles compounds repellent activity against insect, were found only on non-infested plants. Botrytis was restricted to infested plants. The behavioral responses and preferences of P. spumarius for C. myconis plants colonized by these endophytes should be investigated in the future.This work is funded by national funds through the Foundation for Science and Technology - FCT - in the scope of the project PTDC/AGR-PRO/0856/2014 XF-FREEOLIVE: Multifunctional study of xylem-sap of Portuguese olive cultivars and its relation with susceptibility to infection by Xylella fastidiosa, and by European fund in the scope of the project H2020-SFS-2016-3 XF-ACTORS - Xylella fastidiosa active containment through a multidisciplinary-oriented research strategyinfo:eu-repo/semantics/publishedVersio

The effect of Philaenus spumarius feeding on the endophytic fungi community of Coleostephus myconis and its possible applicability in the insect biocontrol

Philaenus spumarius was recently confirmed as the European vector for the ongoing Xylella fastidiosa outbreak in the olive orchards of Southern Italy. In the northeast region of Portugal, P. spumarius is widespread and common in olive groves. In these groves was observed that their nymphs feed preferentially on the weed Coleostephus myconis, displaying in the same time period and area different levels of infestation. This work aims to assess the correlation between the fungal endophytic communities inhabiting C. myconis with the feeding preference of P. spumarius. Fungi were isolated from stems, leaves and inflorescences of plants with three levels of P. spumarius infestation (no infestation, moderate and high infestation), collected in an olive grove located in Mirandela. The fungal isolates were further identified by sequencing the ITS region of rDNA and the partial tef1. A total of 138 OTUs belonging to 37 genera were isolated, being Alternaria, Valsa, Cladosporium and Chalastospora the most abundant genera. An increase in overall endophytic fungal abundance and richness was observed across infestation levels, in particular of isolates belonging to Chalastospora and Cladosporium. In contrast, Biscogniauxia, Chaetomium and Stemphylium, decreased across the levels of infestation. Differences in fungal composition between non-infested and infested plants were particularly observed in stems, where the P. spumarius foam nests are present. Some genera were exclusively found either in non-infested or in infested plants. Our survey provides fungal candidates to further evaluate their role in the repellency/attraction of P. spumarius in order to develop new management tools against this insect.info:eu-repo/semantics/publishedVersio

Exploitation of Coleostephus myconis-associated endophytic fungi repel or attract Xylella fastidiosa vector

Xylella fastIdiosa is a bacterium transmitted by insectvectors that cause high losses in a variety ofagriculturally important crops. In Europe, an outbreak ofthe disease was recently detected in olive trees, being Philaenus spumarius só far identífied as the only vector involved in this outbreak. Thus, vector contrai by using bait plants and/or insect repellents that emit volatile compounds produced by microorganisms that colonize host plants [endophyte] may help to reduce the dissemination ofthe disease. In this work the endophytic fungal community of Coleostephus myconis, a ground cover plant present in the olive graves and commonly infested by P. spumarius, was studied. Fungi were isolated from stems, leaves and inflorescences ofplants with three leveis of P. spumarius infestation, collected in an olive grove located in Mirandela. The fungal isolates obtained were identified by sequencing the ITS region of rDNA the partial tefl. A total of 121 species/genera were identified, bemg Alternaria, Chalastospora and Valsa the most abundant genera. The diversity and abundance of endophytic fungi was higher in the leaf and inflorescences than in the stem. The composition and diversity of endophytic fungal community was different between infested and non-infested plants, especially at the levei of their leaves. Endophyte community similarity between the different plant organs was low, especially between stem and inflorescences. Altogether, the results show that P. spumaríus affects the composition and structure ofendophytic fungal community associated to C. myconis, especially in their leaves. The effect of this change in the fungal community in attractiveness/ repulsion of P. spumarius should be studied in the future.info:eu-repo/semantics/publishedVersio

Brazilian Flora 2020: Leveraging the power of a collaborative scientific network

International audienceThe shortage of reliable primary taxonomic data limits the description of biological taxa and the understanding of biodiversity patterns and processes, complicating biogeographical, ecological, and evolutionary studies. This deficit creates a significant taxonomic impediment to biodiversity research and conservation planning. The taxonomic impediment and the biodiversity crisis are widely recognized, highlighting the urgent need for reliable taxonomic data. Over the past decade, numerous countries worldwide have devoted considerable effort to Target 1 of the Global Strategy for Plant Conservation (GSPC), which called for the preparation of a working list of all known plant species by 2010 and an online world Flora by 2020. Brazil is a megadiverse country, home to more of the world's known plant species than any other country. Despite that, Flora Brasiliensis, concluded in 1906, was the last comprehensive treatment of the Brazilian flora. The lack of accurate estimates of the number of species of algae, fungi, and plants occurring in Brazil contributes to the prevailing taxonomic impediment and delays progress towards the GSPC targets. Over the past 12 years, a legion of taxonomists motivated to meet Target 1 of the GSPC, worked together to gather and integrate knowledge on the algal, plant, and fungal diversity of Brazil. Overall, a team of about 980 taxonomists joined efforts in a highly collaborative project that used cybertaxonomy to prepare an updated Flora of Brazil, showing the power of scientific collaboration to reach ambitious goals. This paper presents an overview of the Brazilian Flora 2020 and provides taxonomic and spatial updates on the algae, fungi, and plants found in one of the world's most biodiverse countries. We further identify collection gaps and summarize future goals that extend beyond 2020. Our results show that Brazil is home to 46,975 native species of algae, fungi, and plants, of which 19,669 are endemic to the country. The data compiled to date suggests that the Atlantic Rainforest might be the most diverse Brazilian domain for all plant groups except gymnosperms, which are most diverse in the Amazon. However, scientific knowledge of Brazilian diversity is still unequally distributed, with the Atlantic Rainforest and the Cerrado being the most intensively sampled and studied biomes in the country. In times of “scientific reductionism”, with botanical and mycological sciences suffering pervasive depreciation in recent decades, the first online Flora of Brazil 2020 significantly enhanced the quality and quantity of taxonomic data available for algae, fungi, and plants from Brazil. This project also made all the information freely available online, providing a firm foundation for future research and for the management, conservation, and sustainable use of the Brazilian funga and flora