Genome-wide footprints in the carob tree (Ceratonia siliqua) unveil a new domestication pattern of a fruit tree in the Mediterranean

Intense research efforts over the last two decades have renewed our understanding of plant phylogeography and domestication in the Mediterranean basin. Here we aim to investigate the evolutionary history and the origin of domestication of the carob tree (Ceratonia siliqua), which has been cultivated for millennia for food and fodder. We used >1000 microsatellite genotypes to delimit seven carob evolutionary units (CEUs). We investigated genome-wide diversity and evolutionary patterns of the CEUs with 3557 single nucleotide polymorphisms generated by restriction-site associated DNA sequencing (RADseq). To address the complex wild vs. cultivated status of sampled trees, we classified 56 sampled populations across the Mediterranean basin as wild, seminatural or cultivated. Nuclear and cytoplasmic loci were identified from RADseq data and separated for analyses. Phylogenetic analyses of these genomic-wide data allowed us to resolve west-to-east expansions from a single long-term refugium probably located in the foothills of the High Atlas Mountains near the Atlantic coast. Our findings support multiple origins of domestication with a low impact on the genetic diversity at range-wide level. The carob was mostly domesticated from locally selected wild genotypes and scattered long-distance westward dispersals of domesticated varieties by humans, concomitant with major historical migrations by Romans, Greeks and Arabs. Ex situ efforts to preserve carob genetic resources should prioritize accessions from both western and eastern populations, with emphasis on the most differentiated CEUs situated in southwest Morocco, south Spain and eastern Mediterranean. Our study highlights the relevance of wild and seminatural habitats in the conservation of genetic resources for cultivated trees

PHYLOPYR: The genetic information of Pyrenean flowering plants accessible worldwide

Póster presentado en el XX International Botanical Congress. Madrid, 21-27 julio 202

Impacto a longo prazo da pastagem e do cultivo na qualidade do solo no Chaco semi-árido (Argentina)

La deforestación del bosque nativo chaqueño y la reorientación del uso del suelo están en camino de transformar la región hacia uso agrícola. El principal objetivo de este trabajo es evaluar el impacto de diferentes prácticas de uso sobre la calidad del suelo en el Chaco semiárido (Argentina). Estudiamos el comportamiento de parámetros edáficos a lo largo de cuatro años de condiciones experimentales: 1) Clausura (EP) usada como nivel de referencia, 2) Ganadería pastoril (GP), 3) Agricultura vía siembra directa (ZT) y 4) Agricultura vía labranza convencional (CT). Se midieron los parámetros de carbono orgánico del suelo, carbono orgánico (C) particulado y pesado, nitrógeno total (N), C:N ratio, pH, conductividad eléctrica y respiración del suelo. Las muestras fueron tomadas anualmente a 0-5, 5-20 y 20-40 cm de profundidad de suelo. Las diferencias entre tratamientos a lo largo del tiempo fueron evaluadas por un Análisis de Covarianza (ANCOVA) con el tiempo (años) como covariable, los tratamientos como factor grupal y los valores de los componentes resultantes del Análisis de Componentes Principales (PCA) como respuestas. Se detectaron cambios correlacionados con las características del suelo, especialmente en la capa superficial del suelo. Los contenidos de nutrientes incrementaron en los sistemas GP y ZT. Una tendencia opuesta fue detectada para CT donde, además, hubo un impacto negativo sobre la salinidad. Tanto el cambio en el uso del suelo como en las prácticas de manejo dentro de la región del Chaco representan las principales actividades humanas que modifican el paisaje; de esta forma, estas deberían ser analizadas reconociendo la heterogeneidad en las prácticas de producción e identificando sus impactos en sitios específicos. Los resultados de este trabajo refuerzan la utilidad del carbono orgánico del suelo como parámetro individual para monitorear sistemas de manejo de la tierra, especialmente regiones extensas como Chaco que están sujetas a continuos procesos de transformación.A desflorestação da mata nativa do Chaco e a reorientação do uso do solo estão a transformar a região no sentido do seu uso agrícola. O principal objetivo deste trabalho é avaliar o impacto de diferentes práticas de uso na qualidade do solo no Chaco semi-árido. Foi estudado o comportamento, ao longo de quatro anos, dos parâmetros edáficos em condições experimentais: 1) Pastagem de exclusão (PE) utilizada como nível de referência, 2) Pastagem Ativa (GP), 3) Pastagem transformada em agricultura com sementeira direta (ZT) e 4) Pastagem transformada em agricultura sob preparação convencional (CT). Determinou-se no solo o carbono orgânico, o carbono orgânico particulado e pesado (C), o nitrogénio total (N), a relação C:N, pH, condutividade elétrica e a respiração do solo. As amostras de solo foram colhidas anualmente a 0-5, 5-20 e 20-40 cm de profundidade. As diferenças entre tratamentos ao longo do tempo foram avaliadas por Análise de Covariância (ANCOVA) com o tempo (anos) como uma covariável, os tratamentos como fator de grupo e os valores dos componentes resultantes de Análise de Componentes Principais (PCA) como respostas. Foram detetadas alterações correlacionadas com as características do solo, principalmente na sua camada superficial. As concentrações em carbono e nitrogénio aumentaram nos sistemas GP e ZT. Uma tendência oposta foi observada para o sistema TC, onde, além disso, houve um impacto negativo na salinidade. A mudança no uso da terra e as práticas de gestão na região do Chaco representam as principais atividades humanas que modificam a paisagem. Deste modo, estas deveriam ser analisadas reconhecendo a heterogeneidade das práticas de produção e identificando os seus impactos em locais específicos. Os resultados deste trabalho reforçam a utilidade do carbono orgânico do solo como um parâmetro individual para monitorizar os sistemas de gestão da terra, especialmente em regiões de grande dimensão como a região de Chaco que estão sujeitas a processos contínuos de transformação.Deforestation of Chacoan native forests and reorientation of land use are transforming the region into agricultural use. The main purpose of this work was to evaluate the impact of different land uses on soil quality in the semi-arid Chaco (Argentina). We assessed the behaviour of soil parameters over four years of experimental conditions: 1) Exclosure pasture (EP) used as reference level, 2) Grazed pasture (GP), 3) Grazed pasture transformed to agriculture with Zero tillage (ZT) and 4) Grazed pasture transformed to agriculture under Conventional tillage (CT). Soil organic carbon, particulate and heavy organic carbon (C), total nitrogen (N), C:N ratio, pH, electric conductivity and soil respiration were measured. Soil samples were taken yearly at 0-5, 5-20 and 20-40 cm of soil depth. Differences among treatments across time were assessed by Analysis of Covariance (ANCOVA) with time (years) as covariate factor, treatments as group factor and individual scores from Principal Component Analysis (PCA) as responses. Correlated changes in the soil characteristics were detected, especially at the top soil layer. Both carbon and nitrogen contents increased in both GP and ZT systems. An opposite trend was found for CT, which also had a negative impact on salinity. Both land use change and management practices in the Chaco region represent the main human activities that modify the landscape; thus, they should be analysed by recognizing heterogeneity on farming practices and identifying their impacts on a specific site. The results of this work reinforce the utility of soil organic carbon as a single parameter for monitoring land management systems, especially for monitoring large region like Chaco that are subject to continuous transformation processes.Fil: Banegas, Natalia Romina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Investigación Animal del Chaco Semiárido; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Tucumán; ArgentinaFil: Maza, M.. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Investigación Animal del Chaco Semiárido; ArgentinaFil: Viruel, Emilce. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Investigación Animal del Chaco Semiárido; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Nasca, Jose Andres. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Investigación Animal del Chaco Semiárido; ArgentinaFil: Canteros, Francisco Humberto. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Investigación Animal del Chaco Semiárido; Argentina. Universidad Nacional de Tucumán; ArgentinaFil: Corbella, Roberto Daniel. Universidad Nacional de Tucumán; ArgentinaFil: Dos Santos, Daniel Andrés. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Biodiversidad Neotropical. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Instituto de Biodiversidad Neotropical. Instituto de Biodiversidad Neotropical; Argentin

Current knowledge, status and future for plant and fungal diversity in Great Britain and the UK Overseas Territories

Societal Impact Statement We rely on plants and fungi for most aspects of our lives. Yet plants and fungi are under threat, and we risk losing species before we know their identity, roles, and potential uses. Knowing names, distributions, and threats are first steps toward effective conservation action. Accessible products like field guides and online resources engage society, harnessing collective support for conservation. Here, we review current knowledge of the plants and fungi of the UK and UK Overseas Territories, highlighting gaps to help direct future research efforts toward conserving these vital elements of biodiversity. Summary This review summarizes current knowledge of the status and threats to the plants and fungi of Great Britain and the UK Overseas Territories (UKOTs). Although the body of knowledge is considerable, the distribution of information varies substantially, and we highlight knowledge gaps. The UK vascular flora is the most well studied and we have a relatively clear picture of its 9,001 native and alien taxa. We have seedbanked 72% of the native and archaeophyte angiosperm taxa and 78% of threatened taxa. Knowledge of the UKOTs flora varies across territories and we report a UKOTs flora comprising 4,093 native and alien taxa. We have conserved 27% of the native flora and 51% of the threatened vascular plants in Kew's Millennium Seed Bank, UK. We need a better understanding of the conservation status of plants in the wild, and progress toward completion or updating national red lists varies. Site‐based protection of key plant assemblages is outlined, and progress in identifying Important Plant Areas analyzed. Knowledge of the non‐vascular flora, especially seaweeds remains patchy, particularly in many UKOTs. The biggest gaps overall are in fungi, particularly non‐lichenized fungi. Considerable investment is needed to fill these knowledge gaps and instigate effective conservation strategies

Identification of a major QTL for Xanthomonas arboricola pv. pruni resistance in apricot

Xanthomonas arboricola pv. pruni causes bacterial spot of stone fruit resulting in severe yield losses in apricot production systems. Present on all continents, the pathogen is regulated in Europe as a quarantine organism. Host resistance is an important component of integrated pest management; however, little work has been done describing resistance against X. arboricola pv. pruni. In this study, an apricot population derived from the cross “Harostar” × “Rouge de Mauves” was used to construct two parental genetic maps and to perform a quantitative trait locus analysis of resistance to X. arboricola pv. pruni. A population of 101 F1 individuals was inoculated twice for two consecutive years in a quarantine greenhouse with a mixture of bacterial strains, and disease incidence and resistance index data were collected. A major QTL for disease incidence and resistance index accounting respectively for 53 % (LOD score of 15.43) and 46 % (LOD score of 12.26) of the phenotypic variation was identified at the same position on linkage group 5 of “Rouge de Mauves.” Microsatellite marker UDAp-452 co-segregated with the resistance, and two flanking microsatellites, namely BPPCT037 and BPPCT038A, were identified. When dividing the population according to the alleles of UDAp-452, the subgroup with unfavorable allele had a disease incidence of 32.6 % whereas the group with favorable allele had a disease incidence of 21 %, leading to a reduction of 35.6 % in disease incidence. This study is a first step towards the marker-assisted breeding of new apricot varieties with an increased tolerance to X. arboricola pv. pruni

Construction of an almond linkage map in an Australian population Nonpareil × Lauranne

Background: Despite a high genetic similarity to peach, almonds (Prunus dulcis) have a fleshless fruit and edible kernel, produced as a crop for human consumption. While the release of peach genome v1.0 provides an excellent opportunity for almond genetic and genomic studies, well-assessed segregating populations and the respective saturated genetic linkage maps lay the foundation for such studies to be completed in almond. Results: Using an almond intraspecific cross between ‘Nonpareil’ and ‘Lauranne’ (N × L), we constructed a moderately saturated map with SSRs, SNPs, ISSRs and RAPDs. The N × L map covered 591.4 cM of the genome with 157 loci. The average marker distance of the map was 4.0 cM. The map displayed high synteny and colinearity with the Prunus T × E reference map in all eight linkage groups (G1-G8). The positions of 14 mapped gene-anchored SNPs corresponded approximately with the positions of homologous sequences in the peach genome v1.0. Analysis of Mendelian segregation ratios showed that 17.9% of markers had significantly skewed genotype ratios at the level of P < 0.05. Due to the large number of skewed markers in the linkage group 7, the potential existence of deleterious gene(s) was assessed in the group. Integrated maps produced by two different mapping methods using JoinMap® 3 were compared, and their high degree of similarity was evident despite the positional inconsistency of a few markers. Conclusions: We presented a moderately saturated Australian almond map, which is highly syntenic and collinear with the Prunus reference map and peach genome V1.0. Therefore, the well-assessed almond population reported here can be used to investigate the traits of interest under Australian growing conditions, and provides more information on the almond genome for the international community.Iraj Tavassolian, Gholmereza Rabiei, Davina Gregory, Mourad Mnejja, Michelle G Wirthensohn, Peter W Hunt, John P Gibson, Christopher M Ford, Margaret Sedgley, and Shu-Biao W

State of the world’s plants and fungi 2020

Kew’s State of the World’s Plants and Fungi project provides assessments of our current knowledge of the diversity of plants and fungi on Earth, the global threats that they face, and the policies to safeguard them. Produced in conjunction with an international scientific symposium, Kew’s State of the World’s Plants and Fungi sets an important international standard from which we can annually track trends in the global status of plant and fungal diversity