Phenotypic instability and epigenetic variability in a diploid potato of hybrid origin, Solanum ruiz-lealii

<p>Abstract</p> <p>Background</p> <p>The wild potato <it>Solanum ruiz-lealii </it>Brüch. (2n = 2x = 24), a species of hybrid origin, is endemic to Mendoza province, Argentina. Recurrent flower malformations, which varied among inflorescences of the same plant, were observed in a natural population. These abnormalities could be the result of genomic instabilities, nucleus-cytoplasmic incompatibility or epigenetic changes. To shed some light on their origin, nuclear and mitochondrial DNA of plants with normal and plants with both normal and malformed flowers (from here on designated as plants with normal and plants with abnormal flower phenotypes, respectively) were analyzed by AFLP and restriction analyses, respectively. Also, the wide genome methylation status and the level of methylation of a repetitive sequence were studied by MSAP and Southern blots analyses, respectively.</p> <p>Results</p> <p>AFLP markers and restriction patterns of mitochondrial DNA did not allow the differentiation of normal from abnormal flower phenotypes. However, methylation patterns of nuclear DNA discriminated normal and abnormal flower phenotypes into two different groups, indicating that abnormal phenotypes have a similar methylation status which, in turn, was different from the methylation patterns of normal phenotypes. The abnormal flower phenotype was obtained by treating a normal plant with 5-Azacytidine, a demethylating agent, giving support to the idea of the role of DNA methylation in the origin of flower abnormalities. In addition, the variability detected for DNA methylation was greater than the detected for nucleotide sequence.</p> <p>Conclusion</p> <p>The epigenetic nature of the observed flower abnormalities is consistent with the results and indicates that in the diploid hybrid studied, natural variation in methylation profiles of anonymous DNA sequences could be of biological significance.</p

Brighter-colored paper wasps (Polistes dominula) have larger poison glands

Introduction Aposematism is a defense system against predators consisting of the toxicity warning using conspicuous coloration. If the toxin production and aposematic coloration is costly, only individuals in good physical condition could simultaneously produce abundant poison and striking coloration. In such cases, the aposematic coloration not only indicates that the animal is toxic, but also the toxicity level of individuals. The costs associated with the production of aposematic coloration would ensure that individuals honestly indicate their toxicity levels. In the present study, we examine the hypothesis that a positive correlation exists between the brightness of warning coloration and toxicity level using as a model the paper wasp (Polistes dominula). Results We collected wasps from 30 different nests and photographed them to measure the brightness of warning coloration in the abdomen. We also measured the volume of the poison gland, as well as the length, and the width of the abdomen. The results show a positive relationship between brightness and poison-gland size, which remained positive even after controlling for the body size and abdomen width. Conclusion The results suggest that the coloration pattern of these wasps is a true sign of toxicity level: wasps with brighter colors are more poisonous (they have larger poison glands)

Two super-Earths at the edge of the habitable zone of the nearby M dwarf TOI-2095

The main scientific goal of TESS is to find planets smaller than Neptune around stars bright enough to allow further characterization studies. Given our current instrumentation and detection biases, M dwarfs are prime targets to search for small planets that are in (or nearby) the habitable zone of their host star. Here we use photometric observations and CARMENES radial velocity measurements to validate a pair of transiting planet candidates found by TESS. The data was fitted simultaneously using a Bayesian MCMC procedure taking into account the stellar variability present in the photometric and spectroscopic time series. We confirm the planetary origin of the two transiting candidates orbiting around TOI-2095 (TIC 235678745). The star is a nearby M dwarf ($d = 41.90 \pm 0.03$ pc, $T_{\rm eff} = 3759 \pm 87$ K, $V = 12.6$ mag) with a stellar mass and radius of $M_\star = 0.44 \pm 0.02 \; M_\odot$ and $R_\star = 0.44 \pm 0.02 \; R_\odot$, respectively. The planetary system is composed of two transiting planets: TOI-2095b with an orbital period of $P_b = 17.66484 \pm (7\times 10^{-5})$ days and TOI-2095c with $P_c = 28.17232 \pm (14\times 10^{-5})$ days. Both planets have similar sizes with $R_b = 1.25 \pm 0.07 \; R_\oplus$ and $R_c = 1.33 \pm 0.08 \; R_\oplus$ for planet b and c, respectively. We put upper limits on the masses of these objects with $M_b < 4.1 \; M_\oplus$ for the inner and $M_c < 7.4 \; M_\oplus$ for the outer planet (95\% confidence level). These two planets present equilibrium temperatures in the range of 300 - 350 K and are close to the inner edge of the habitable zone of their star.Comment: Submitted to Astronomy & Astrophysic

In situ conservation of wild potato germplasm in Argentina: Example and possibilities

The potato is the third most important food crop worldwide and in situ conservation of its wild relatives is considered an urgent priority. Although regions of the Americas with high wild potato species richness have been identified, the need to identify specific sites for establishing genetic reserves is still pending. Matching distribution data of Argentinean wild potato species to existing protected areas (PA), two priority sites were identified. The creation of genetic reserves in these two PA would make possible to preserve populations of species that have been successfully incorporated into the crop and are listed in the global priority Crop Wild Relative inventory. While the presence of target species in PA could ensure a passive conservation, in situ conservation programs require to actively intervene in selected areas. From a field study performed on populations of the wild potato Solanum kurtzianum naturally growing in a PA, the Villavicencio Natural Reserve (Mendoza province), a baseline with distribution, biotic interactions, sprouting behavior, population dynamics, AFLP and pollen viability data was established. Based on a systematic work in this Reserve we have generated a working protocol to be implemented at national and regional levels for the in situ conservation of potato wild relatives

Variation in the amino acids, volatile organic compounds and terpenes profiles in induced polyploids and in Solanum tuberosum varieties

Polyploids often display a variety of phenotypic novelties when compared to their diploid progenitors, some of which may represent ecological advantages, especially regarding tolerance to biotic and abiotic factors. Plants cope with environmental factors by producing chemicals such as volatile organic compounds (VOCs) and specific amino acids (AAs). In potato, the third most important food crop in the world, gene introgression from diploid wild relative species into the genetic pool of the cultivated species (tetraploid) would be of great agronomical interest. The consequences of allopolyploidization on the potato VOCs and AAs profiles have not been yet analyzed. In this work, the effects of whole genome duplication on VOCs and AAs contents in leaves of potato allo- and autotetraploids and cultivated varieties were studied. The polyploids were obtained by chromosomal duplication of a genotype of the wild diploid species S. kurtzianum (autopolyploid model), and a diploid interspecific hybrid between the cultivated species S. tuberosum and S. kurtzianum (allopolyploid model). Almost all compounds levels varied greatly among these tetraploid lines; while all tetraploids showed higher contents of non-isoprenoids compounds than diploids, we found either increments or reductions in terpenes and AAs content. The results support the idea that genome duplication is a stochastic source of variability, which might be directly used for introgression in the 4x gene pool of the cultivated potato by sexual hybridization.Fil: Cara, Nicolás. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Piccoli, Patricia Noemí. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Biología Agrícola de Mendoza. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Instituto de Biología Agrícola de Mendoza; ArgentinaFil: Bolcato, Leonardo Emilio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Biología Agrícola de Mendoza. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Instituto de Biología Agrícola de Mendoza; ArgentinaFil: Marfil, Carlos Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Biología Agrícola de Mendoza. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Instituto de Biología Agrícola de Mendoza; ArgentinaFil: Masuelli, Ricardo Williams. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Biología Agrícola de Mendoza. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Instituto de Biología Agrícola de Mendoza; Argentin

Fig. 3 in Variation in the amino acids, volatile organic compounds and terpenes profiles in induced polyploids and in Solanum tuberosum varieties

Fig. 3. Hierarchical cluster analysis (represented by a heat-map) of amino acids content in leaves of potato allo- and autotetraploids and cultivated varieties. Dendrograms were constructed by UPGMA clustering method for 18 amino acids and 10 lines: diploid S. kurtzianum parental line (2xPL), diploid S. tuberosum x S. kurtzianum parental interspecific hybrid (2xPIH), three autotetraploids (4xAuL1, 4xAuL2 and 4xAuL3), two allotetraploids (4xAL2 and 4xAL4) and three cultivated varieties (4xCalen, 4xInnovator and 4xPampeana).Published as part of &lt;i&gt;Nicol, Cara, as, Piccoli, Patricia N., Bolcato, Leonardo, Marfil, Carlos F. &amp; Masuelli, Ricardo W., 2020, Variation in the amino acids, volatile organic compounds and terpenes profiles in induced polyploids and in Solanum tuberosum varieties, pp. 1-8 in Phytochemistry (112516) 180&lt;/i&gt; on page 6, DOI: 10.1016/j.phytochem.2020.112516, &lt;a href="http://zenodo.org/record/10126992"&gt;http://zenodo.org/record/10126992&lt;/a&gt

Organic matter and diagenesis of the Mas d'Ascla marls formation (Upper Jurassic) in the Maestrat basin (Eastern Iberian basin)

The Mas d'Ascla marls Fm. (Upper Kimmeridgian to lowermost Tithonian) in the Maestrat Basin (Salzedella sub-basin, Castellò de la Plana) displays two organic-carbon-rich horizons which indicate anoxic conditions. The maximum anoxic event is located at the base of the formation corresponding to the lower part of the trangressive system tract. In both horizons the kerogen is mainly of marine origin with algal and amorphous sapropelic organic matter, a low organic carbon content (0.5% - 1.26%) and a low potential yield of hydrocarbons (HC). These data and the Tmax. suggest a mature source-rock which has already generated nearly all HC. Extractable organic matter is fundamentally composed of asphaltenes and resins predominating over saturate and aromatic compounds which have been probably expulsed out of the source rock.Generalitat de CatalunyaDepto. de Mineralogía y PetrologíaFac. de Ciencias GeológicasTRUEpu