Biodeterioration and cellulolytic activity by fungi isolated from a nineteenth-century painting at the National Theatre of Costa Rica

Living organisms can induce deterioration of cultural heritage. Conservation strategies aimed at avoiding damage and aiding restoration, require a comprehensive knowledge of structure, chemical composition, and identity of microorganisms that colonize artworks. The National Theatre of Costa Rica (NTCR), a building with historic architecture, houses several oil paintings from the nineteenth century, some with visible signs of biodeterioration. One of them is a large format painting on canvas called La Danza (size 9.83 × 5.13 m) from 1896 by Italian artist Vespasiano Bignami, located on the ceiling of the theatre's foyer. In the present study, we undertook a physicochemical and microbiological study of La Danza to identify the fungal species that inhabit the artwork and are responsible for the damage observed. Scanning electron microscope (SEM) images and attenuated total reflectance - Fourier transform infrared (ATR-FTIR) spectroscopic data indicated that the canvas material is made of hemp, the binder contains linseed oil and lead white, and a material in the inner face of the canvas is mainly composed of beeswax. Fungi were isolated onto potato dextrose agar (PDA) and carboxymethyl cellulose (CMC) agar, and then identified with molecular (BTUB, nrDNA ITS, and TEF1 regions) and morphological methods. Four isolates belonging to the genera Myxospora, Pestalotiopsis, Ustilago, and aff. Penicillium, were obtained. Qualitative tests showed cellulolytic activity in all isolated specimens, confirming their possible role in biodeterioration of the canvas. Phylogenetic and morphological data revealed a new species of Myxospora we name here as Myxospora theatro sp. nov., in reference to NTCR. The findings broaden the knowledge of fungi capable of inhabiting and damaging cultural heritage. They also provide valuable information to develop strategies for conservation and restoration of oil paintings on canvas.     

Integrative taxonomy recognized a new cryptic species within Stipa grandis from Loess Plateau of China

Stipa shanxiensis, a cryptic species within Stipa grandis that originated from central and western China, is described based on morphological, genomic, and ecological data from field and common garden experiments. Stipa shanxiensis morphologically resembles S. grandis, although phylogenetically it is closely related to the less morphologically similar Stipa baicalensis and Stipa krylovii. Of the eight significant morphological differences between S. shanxiensis and S. grandis, the two, cauline ligules longer than 2 cm with a filiform apex, and hairs shorter than 0.2 mm on the adaxial surface of the cauline uppermost leaves can be used to distinguish the species. Results from a common garden experiment verified that the two diagnostic characteristics were relatively stable and less morphologically plastic in response to environmental variation. Furthermore, a significant ecological divergence was found between S. shanxiensis and S. grandis, such that the former preferred warmer and more humid climates, and their predicted distribution was generally separated. Taken together, our results highlight that the integrative taxonomic approach was valuable for recognizing a new cryptic species in Stipa. In particular, we find that common garden experiments involving the effects of growth stage and characteristic position helped to morphologically diagnose cryptic species. These findings may also facilitate our understandings of ecological adaption and phenotypic plasticity in response to environmental change.     

Development of Oryza rufipogon and O. sativa Introgression Lines and Assessment for Yield-related Quantitative Trait Loci

Introgression lines population was effectively used in mapping quantitative trait loci （QTLs）, identifying favorable genes, discovering hidden genetic variation, evaluating the action or interaction of QTLs in multiple conditions and providing the favorable experimental materials for plant breeding and genetic research. In this study, an advanced backcross and consecutive selfing strategy was used to develop introgression lines （ILs）, which derived from an accession of Oryza rufipogon Griff. collected from Yuanjiang County, Yunnan Province of China, as the donor, and an elite indica cultivar Teqing （O. sativa L.）, as the recipient. Introgression segments from O. rufipogon were screened using 179 polymorphic simple sequence repeats （SSR） markers in the genome of each IL. Introgressed segments carried by the introgression lines population contained 120 ILs covering the whole O. rufipogon genome. The mean number of homozygous O. rufipogon segments per introgression line was about 3.88. The average length of introgressed segments was approximate 25.5 cM, and about 20.8% of these segments had sizes less than 10 cM. The genome of each IL harbored the chromosomal fragments of O. rufipogon ranging from 0.54% to 23.7%, with an overall average of 5.79%. At each locus, the ratio of substitution of O. rufipogon alleles had a range of 1.67-9.33, with an average of 5.50. A wide range of alterations in morphological and yield-related traits were also found in the introgression lines population. Using single-point analysis, a total of 37 putative QTLs for yield and yield components were detected at two sites with 7%-20% explaining the phenotypic variance. Nineteen QTLs （51.4%） were detected at both sites, and the alleles from O. rufipogon at fifteen loci （40.5%） improved the yield and yield components in the Teqing background. These O. rufipogon-O, sativa introgression lines will serve as genetic materials for identifying and using favorable genes from common wild rice.     

Using unmanned aerial vehicle‐based multispectral,RGB and thermal imagery for phenotyping of forest genetic trials: A case study in Pinus halepensis

The assessment of genetic differentiation in functional traits is fundamental towards understanding the adaptive characteristics of forest species. While traditional phenotyping techniques are costly and time‐consuming, remote sensing data derived from cameras mounted on unmanned aerial vehicles (UAVs) provide potentially valid high‐throughput information for assessing morphophysiological differences among tree populations. In this work, we test for genetic variation in vegetation indices (VIs) and canopy temperature among populations of Pinus halepensis as proxies for canopy architecture, leaf area, photosynthetic pigments, photosynthetic efficiency and water use. The interpopulation associations between vegetation properties and above‐ground growth (stem volume) were also assessed. Three flights (July 2016, November 2016 and May 2017) were performed in a genetic trial consisting of 56 populations covering a large part of the species range. Multispectral (visible and near infrared wavelengths), RGB (red, green, blue) and thermal images were used to estimate canopy temperature and vegetation cover (VC) and derive several VIs. Differences among populations emerged consistently across flights for VC and VIs related to leaf area, indicating genetic divergence in crown architecture. Population differences in indices related to photosynthetic pigments emerged only in May 2017 and were probably related to a contrasting phenology of needle development. Conversely, the low population differentiation for the same indices in July 2016 and November 2016 suggested weak interpopulation variation in the photosynthetic machinery of mature needles of P. halepensis. Population differences in canopy temperature found in July 2016 were indicative of variation in stomatal regulation under drought stress. Stem volume correlated with indices related to leaf area (positively) and with canopy temperature (negatively), indicating a strong influence of canopy properties and stomatal conductance on above‐ground growth at the population level. Specifically, a combination of VIs and canopy temperature accounted for about 60% of population variability in stem volume of adult trees. This is the first study to propose UAV remote sensing as an effective tool for screening genetic variation in morphophysiological traits of adult forest trees.     

Standard metabolic rate models for Carmine Shiner (Notropis percobromus) and Common Shiner (Luxilus cornutus) across different temperature regimes

Standard metabolic rates (SMR) were measured empirically for carmine shiner Notropis percobromus and common shiner Luxilus cornutus to develop SMR models that predict metabolic responses of each species under thermal conditions observed in the wild. SMR increased significantly with body mass and rising water temperature, ranging from 0.05 mg O₂ h⁻¹ at 10°C to 0.89 mg O₂ h⁻¹ at 20°C for N. percobromus weighing 0.6–2.5 g and from 0.11 mg O₂ h⁻¹ at 10°C to 0.98 mg O₂ h⁻¹ at 20°C for L. cornutus weighing 0.8–6.6 g. SMR models significantly differed between sympatric species on account of differences in model intercepts (RA) and temperature coefficients (RQ), however, the allometric relationships between mass and SMR did not significantly differ between species. Known distribution of N. percobromus and L. cornutus includes the Birch River located in Manitoba, Canada, where N. percobromus is listed as Endangered. Little is known about the physiology of N. percobromus or the species' ability to acclimate or adapt to different environmental conditions. While size differences between species contributed, in part, to differences in SMR predictions for Birch River populations, SMR trends (< 2 mg O₂ h⁻¹) for individuals weighing 1 g were similar for both species across daily temperatures. Respirometry experiments contributed to developing species-specific SMR models and inform on the effect of natural and anthropogenic stressors, namely water temperature, on the conservation of N. percobromus in this ecosystem.     

The function of three main call types in common cuckoo

Acoustic signals play a key role in shaping the relationships in birds. Common cuckoos Cuculus canorus are known to produce various call types, but the function of these calls has only been studied recently. Here, we used a combination of field recordings (conducted in 2017) and playback experiments (conducted in 2018) to investigate the functional significance of common cuckoo calls. We found significant differences in the characteristics between male two‐element “cu‐coo” and three‐element “cu‐cu‐coo” calls, with these two call types being used in different contexts. The three‐element male “cu‐cu‐coo” calls were associated with females emitting their “bubbling” call. Playback experiments revealed that both males and females exhibit stronger responses to playing female “bubbling” calls than with the calls of the Eurasian sparrowhawk (Accipter nisus) serving as a control, suggesting a significant intraspecific communication function for this call type. However, we did not find any evidence to support mate attraction in male calls, as females were not stimulated by playback of male calls compared with sparrowhawk calls in the control group.     

褪黑素对盐胁迫下普通菜豆芽期核酸修复的调控机制

普通菜豆(Phaseolus vulgaris)是重要的食用豆作物,然而其极易受盐胁迫危害,导致产量下降。褪黑素能提高植物耐盐能力。为探明外源褪黑素调控普通菜豆耐盐能力的机制,以普通菜豆品种奶花芸豆(GZ-YD014)为实验材料,设置水(W,对照)、盐胁迫(S)和盐胁迫+100μmol·L^–1褪黑素(M+S) 3个处理。结果发现,盐胁迫抑制了普通菜豆胚根的生长,使其长度、表面积、体积以及直径显著降低,外源褪黑素可缓解盐胁迫对普通菜豆胚根生长的抑制。外施褪黑素显著降低盐胁迫下活性氧积累和丙二醛(MDA)含量,提高保护酶(过氧化物酶、超氧化物歧化酶、过氧化氢酶以及抗坏血酸过氧化物酶)活性,增加渗透调节物质(可溶性糖和可溶性蛋白)以及生长素(IAA)、赤霉素(GA)和玉米素(ZT)的含量,降低脱落酸(ABA)含量。通过转录组分析挖掘出217个差异表达基因(DEGs),DEGs在GO富集中显著(P-value<0.05)富集到核酸相关条目上,在KEGG富集中显著(P-value<0.05)富集到核酸损伤修复(包括碱基切除修复、错配修复以及核苷酸切除修复)通路。...     

Host in reserve: The role of common shrews (Sorex araneus) as a supplementary source of tick hosts in small mammal communities influenced by rodent population cycles

Rodents often act as important hosts for ticks and as pathogen reservoirs. At northern latitudes, rodents often undergo multi‐annual population cycles, and the periodic absence of certain hosts may inhibit the survival and recruitment of ticks. We investigated the potential role of common shrews (Sorex araneus) to serve as a supplementary host source to immature life stages (larvae and nymphs) of a generalist tick Ixodes ricinus and a small mammal specialist tick I. trianguliceps, during decreasing abundances of bank voles (Myodes glareolus). We used generalized mixed models to test whether ticks would have a propensity to parasitize a certain host species dependent on host population size and host population composition across two high‐latitude gradients in southern Norway, by comparing tick burdens on trapped animals. Host population size was defined as the total number of captured animals and host population composition as the proportion of voles to shrews. We found that a larger proportion of voles in the host population favored the parasitism of voles by I. ricinus larvae (estimate = −1.923, p = .039) but not by nymphs (estimate = −0.307, p = .772). I. trianguliceps larvae did not show a lower propensity to parasitize voles, regardless of host population composition (estimate = 0.875, p = .180), while nymphs parasitized shrews significantly more as vole abundance increased (estimate = 2.106, p = .002). These results indicate that common shrews may have the potential to act as a replacement host during periods of low rodent availability, but long‐term observations encompassing complete rodent cycles may determine whether shrews are able to maintain tick range expansion despite low rodent availability.     

Time course of vocal modulation during isolation in common marmosets (Callithrix jacchus)

Common marmosets vocalize phee calls as isolation calls, which seem to facilitate their reunion with family groups. To identify multiple acoustic properties with different time courses, we examined acoustic modulations of phees during different social contexts of isolation. Subject marmosets were totally isolated in one condition, were visually isolated and could exchange vocalizations in another condition, and were visually isolated and subsequently totally isolated in a third condition. We recorded 6,035 phees of 10 male–female marmoset pairs and conducted acoustic analysis. The marmosets frequently vocalized phees that were temporally elongated and louder during isolation, with varying time courses of these changes in acoustic parameters. The vocal rates and sound levels of the phees increased as soon as the marmosets saw their pair mates being taken away, and then gradually calmed down. The phee duration was longer in conditions during which there were no vocal responses from their pair mates. Louder vocalizations are conspicuous and seem to be effective for long‐distance transmission, whereas shorter call duration during vocal exchanges might avoid possible vocal overlap between mates. Am. J. Primatol. 72:681–688, 2010. © 2010 Wiley‐Liss, Inc.