ABSTRACT
Earth harbours an extraordinary plant phenotypic diversity1 that is at risk from ongoing global changes2,3. However, it remains unknown how increasing aridity and livestock grazing pressure-two major drivers of global change4-6-shape the trait covariation that underlies plant phenotypic diversity1,7. Here we assessed how covariation among 20 chemical and morphological traits responds to aridity and grazing pressure within global drylands. Our analysis involved 133,769 trait measurements spanning 1,347 observations of 301 perennial plant species surveyed across 326 plots from 6 continents. Crossing an aridity threshold of approximately 0.7 (close to the transition between semi-arid and arid zones) led to an unexpected 88% increase in trait diversity. This threshold appeared in the presence of grazers, and moved toward lower aridity levels with increasing grazing pressure. Moreover, 57% of observed trait diversity occurred only in the most arid and grazed drylands, highlighting the phenotypic uniqueness of these extreme environments. Our work indicates that drylands act as a global reservoir of plant phenotypic diversity and challenge the pervasive view that harsh environmental conditions reduce plant trait diversity8-10. They also highlight that many alternative strategies may enable plants to cope with increases in environmental stress induced by climate change and land-use intensification.
ABSTRACT
Chile has two certified origin olive products: Extra-Virgin Olive Oil (EVOO) from Huasco valley and the Azapa variety table olive from the Azapa valley. However, efficient methodologies are needed to determine the varieties and raw materials involved in the end products. In this study, we assessed the size of alleles from ten microsatellites in 20 EVOOs and in leaves and fruits of 16 olive varieties cultivated in Chile to authenticate their origins. The identification of varieties relied on specific allele sizes derived from microsatellites markers UDO99-011 and DCA18-M found in leaves and fruit mesocarp. While most Chilean single-variety EVOOs matched the variety declared on the label, inconsistencies were observed in single-variety EVOOs containing multiple varieties. Our findings confirm that microsatellites serve as a valuable as diagnostic tools for ensuring the quality control of Geographical Indication certification for Azapa olives and EVOO with Designation of Origin from Huasco.
Chile cuenta con dos productos de oliva de origen certificado: El aceite de oliva virgen extra (AOVE) del valle del Huasco y la aceituna de mesa de la variedad Azapa del valle de Azapa. Sin embargo, se necesitan metodologías eficientes para determinar las variedades y materias primas involucradas en los productos finales. En este estudio, evaluamos el tamaño de los alelos de diez microsatélites en 20 AOVEs y en hojas y frutos de 16 variedades de aceituna cultivadas en Chile para autentificar sus orígenes. La identificación de las variedades se basó en los tamaños alélicos específicos derivados de los marcadores microsatélites UDO99-011 y DCA18-M encontrados en las hojas y el mesocarpio de los frutos. Aunque la mayoría de los AOVEs chilenos monovarietales coincidían con la variedad declarada en la etiqueta, se observaron incoherencias en los AOVEs monovarietales que contenían múltiples variedades. Nuestros hallazgos confirman que los microsatélites sirven como valiosas herramientas de diagnóstico para asegurar el control de calidad de la certificación de Indicación Geográfica para aceitunas de Azapa y AOVE con Denominación de Origen de Huasco.
Subject(s)
Plant Extracts/genetics , Microsatellite Repeats , Olea/genetics , Olive Oil/chemistry , Geography , ChileABSTRACT
Neltuma alba (Algarrobo blanco), Neltuma chilensis (Algarrobo Chileno) and Strombocarpa strombulifera (Fortuna) are some of the few drought resistant trees and shrubs found in small highly fragmented populations, throughout the Atacama Desert. We reconstructed their plastid genomes using de novo assembly of paired-end reads from total genomic DNA. We found that the complete plastid genomes of N. alba and N. chilensis are larger in size compared to species of the Strombocarpa genus. The Strombocarpa species presented slightly more GC content than the Neltuma species. Therefore, we assume that Strombocarpa species have been exposed to stronger natural selection than Neltuma species. We observed high variation values in the number of cpSSRs (chloroplast simple sequence repeats) and repeated elements among Neltuma and Strombocarpa species. The p-distance results showed a low evolutionary divergence within the genus Neltuma, whereas a high evolutionary divergence was observed between Strombocarpa species. The molecular divergence time found in Neltuma and Strombocarpa show that these genera diverged in the late Oligocene. With this study we provide valuable information about tree species that provide important ecosystem services in hostile environments which can be used to determine these species in the geographically isolated communities, and keep the highly fragmented populations genetically healthy.
Subject(s)
Phylogeny , Evolution, Molecular , Desert Climate , Genome, Plastid , Genetic Variation , Base CompositionABSTRACT
Chañar (Geoffroea decorticans (Gill., ex Hook. & Arn.) Burkart) has been highly significant for indigenous people in the Atacama Desert for over 3,000 years. Through evolutionary processes, the G. decorticans mitogenome likely underwent changes facilitating its adaptation to the extreme conditions of the Atacama Desert. Here, we compare the mitochondrial genome of G. decorticans with those of other Papilionoideae family species. The complete mitogenome of G. decorticans was sequenced and assembled, making it the first in the genus Geoffroea. The mitogenome contained 383,963 base pairs, consisting of 33 protein coding genes, 21 transfer RNA genes, and 3 ribosomal RNA genes. The Chañar mitogenome is relatively compact, and has two intact genes (sdh4 and nad1) which were not observed in most other species. Additionally, Chañar possessed the highest amount of mitochondrial DNA of plastid origin among angiosperm species. The phylogenetic analysis of the mitogenomes of Chañar and 12 other taxa displayed a high level of consistency in taxonomic classification, when compared to those of the plastid genome. Atp8 was subjected to positive selection, while the ccmFc and rps1 were subjected to neutral selection. This study provides valuable information regarding its ability to survive the extreme environmental conditions of the Atacama Desert.
ABSTRACT
In a world threatened by climate change and biodiversity loss, Chile is one of the leading countries regarding national park management and nature conservation. While there are already protection strategies for plants and animals, it is now the time to include biocrusts, the microbial world at our feet that covers large parts of the soils from the Araucaria forests in the South of Chile to the Atacama Desert in the North.
Subject(s)
Biodiversity , Parks, Recreational , Chile , SoilABSTRACT
Sporadic rains in the Atacama Desert reveal a high biodiversity of plant species that only occur there. One of these rare species is the "Red añañuca" (Zephyranthes phycelloides), formerly known as Rhodophiala phycelloides. Many species of Zephyranthes in the Atacama Desert are dangerously threatened, due to massive extraction of bulbs and cutting of flowers. Therefore, studies of the biodiversity of these endemic species, which are essential for their conservation, should be conducted sooner rather than later. There are some chloroplast genomes available for Amaryllidaceae species, however there is no complete chloroplast genome available for any of the species of Zephyranthes subgenus Myostemma. The aim of the present work was to characterize and analyze the chloroplast of Z. phycelloides by NGS sequencing. The chloroplast genome of the Z. phycelloides consists of 158,107 bp, with typical quadripartite structures: a large single copy (LSC, 86,129 bp), a small single copy (SSC, 18,352 bp), and two inverted repeats (IR, 26,813 bp). One hundred thirty-seven genes were identified: 87 coding genes, 8 rRNA, 38 tRNA and 4 pseudogenes. The number of SSRs was 64 in Z. phycelloides and a total of 43 repeats were detected. The phylogenetic analysis of Z. phycelloides shows a distinct subclade with respect to Z. mesochloa. The average nucleotide variability (Pi) between Z. phycelloides and Z. mesochloa was of 0.02000, and seven loci with high variability were identified: psbA, trnSGCU-trnGUCC, trnDGUC-trnYGUA, trnLUAA-trnFGAA, rbcL, psbE-petL and ndhG-ndhI. The differences between the species are furthermore confirmed by the high amount of SNPs between these two species. Here, we report for the first time the complete cp genome of one species of the Zephyranthes subgenus Myostemma, which can be used for phylogenetic and population genomic studies.
ABSTRACT
The hybridization of Prosopis burkartii, a critically endangered endemic species, and the identification of its paternal species has not been genetically studied before. In this study we aimed to genetically confirm the origin of this species. To resolve the parental status of P. burkartii, inter-simple sequence repeat (ISSR), simple sequence repeats (SSR) and intron trnL molecular markers were used, and compared with Chilean species from the Algarobia and Strombocarpa sections. Out of seven ISSRs, a total of 70 polymorphic bands were produced in four species of the Strombocarpa section. An Multi-dimensional scaling (MDS) and Bayasian (STRUCTURE) analysis showed signs of introgression of genetic material in P. burkartii. Unweighted pair group method with arithmetic average (UPGMA) cluster analysis showed three clusters, and placed the P. burkartii cluster nested within the P. tamarugo group. Sequencing of the trnL intron showed a fragment of 535 bp and 529 bp in the species of the Algarobia and Strombocarpa sections, respectively. Using maximum parsimony (MP) and maximum likelihood (ML) trees with the trnL intron, revealed four clusters. A species-specific diagnostic method was performed, using the trnL intron Single Nucleotide Polymorphism (SNP). This method identified if individuals of P. burkartii inherited their maternal DNA from P. tamarugo or from P. strombulifera. We deduced that P. tamarugo and P. strombulifera are involved in the formation of P. burkartii.
ABSTRACT
Every 3 to 7 year angiosperms species of the flowering desert appear in the Atacama Region of Chile, as a result of the climatic phenomenon "El Niño". Our objective was to evaluate the universality of matK and rbcL barcode markers of these species, and validate their taxon through phylogenetic relationships. Argemone hunnemannii, Oenothera coquimbensis, Malesherbia humilis, Leucocoryne appendiculata, Loasa elongata, Nicotiana solanifolia, Stachys grandidentata, Aristolochia chilensis, Alstroemeria kingii and Adesmia eremophila, almost all classified as endemic to Chile, were collected in Pan de Azúcar and Llanos de Challe National Park (Atacama Region, Chile) at the end of October 2017. The phylogeny of these ten angiosperm species from the flowering desert was analyzed using rbcL and matK markers with the maximum likelihood and Bayesian inference methods. The results showed that 70% of the species can be distinguished with the matK or rbcL locus, however, 100% were distinguished using both loci. The phylogenetic results showed that the species formed clades with high reliability and high support with both the matK and rbcL genes, when comparing our results with sequences obtained from GenBank. The matK and rbcL genes are efficient markers for analyzing phylogenetic relationships and validating the taxonomy of flowering species.
Las especies de angiospermas del Desierto Florido de la Región de Atacama de Chile aparecen cada 3 a 7 años, influenciado por el fenómeno climático "El Niño". Nuestro objetivo fue evaluar la universalidad de los marcadores de código de barra matK y rbcL de estas especies, y validar su taxón por medio de relaciones filogenéticas. Las especies Argemone hunnemannii, Oenothera coquimbensis, Malesherbia humilis, Leucocoryne appendiculata, Loasa elongata, Nicotiana solanifolia, Stachys grandidentata, Aristolochia chilensis, Alstroemeria kingii y Adesmia eremophila son clasificadas la mayoría endémicas de Chile. Estas especies fueron colectadas en el Parque Nacional Pan de Azúcar y Llanos de Challe, Región de Atacama, Chile. La colecta se realizó a fines de octubre de 2017. Con los marcadores rbcL y matK se analizó la filogenia con los métodos máxima verosimilitud e inferencia bayesiana en diez especies de angiosperma del Desierto Florido. Los resultados mostraron que el 70% de las especies pueden ser distinguidas con un locus matK o rbcL, sin embargo, el 100% se distinguió usando ambos locus. Los resultados filogenéticos mostraron que las especies formaron clados con alta fiabilidad y alto soporte tanto con los genes matK y rbcL, al comparar con accesos de secuencias obtenidas de GenBank. Lo genes matK y rbcL son marcadores eficientes para analizar relaciones filogenéticas y validar el taxón de las especies de flor.