Length-weight relationship for Potamotrygon wallacei (Carvalho, Rosa and Araújo, 2016) caught in the middle Negro River, Barcelos, Brazilian Amazon / Relação peso-comprimento de Potamotrygon wallacei (Carvalho, Rosa e Araújo, 2016) capturada no médio Rio Negro, Barcelos, Amazônia Brasileira

Abstract This research aimed to estimate the length-weight ratio (LWR) of the stingray Potamotrygon wallacei, known locally as the cururu, which was caught in streams and lakes in the middle Negro River region, Amazonas, Brazil. The stingrays were captured during the night (from 11 pm to 1 am) near the shores of streams and lakes, through active search using wooden canoes, head lanterns and scoop nets. The samplings were carried out in November 2017 (5 days), February (8 days), March (3 days) and April (2 days) of 2018, totaling 18 days of sampling. The total fresh weight was measured to 0.1 g of accuracy and the disc width to 0.1 cm accuracy. The parameters a and b of the equation W=a.DWb were estimated. This study provides new maximum length data for the cururu stingray.

Resumo Esta pesquisa teve como objetivo estimar a relação peso-comprimento (LWR) da arraia Potamotrygon wallacei, conhecida localmente como cururu, que foi capturada em igarapés e lagos na região do médio Rio Negro, Amazonas, Brasil. As arraias foram capturadas durante a noite (das 23h-1h) nas margens dos igarapés e lagos, por meio de busca ativa utilizando canoas de madeira, lanternas de cabeça e puçás. As coletas foram realizadas nos meses de novembro de 2017 (5 dias), fevereiro (8 dias), março (3 dias) e abril (2 dias) de 2018, totalizando 18 dias de amostragem. Foram medidos o peso fresco total com precisão de 0,01 g e a largura do disco com precisão de 0,1 cm. Os parâmetros a e b da equação W= a.DWb foram estimados. Este estudo prover novos dados de comprimento máximo para a arraia cururu.

Different LED light spectra's and nano-chelated potassium affect the quality traits of Dolce Vita cut roses in soilless culture condition.

Roses are classified as neutral day plants, but high light and cool temperatures produce high quality flowers in roses. As light quantity, the light quality and its special spectra can affect the flower yield and quality. This research aimed to study of the effect of LED light (control (sunlight), blue and red spectra's) and nano-chelated potassium at three levels (0, 1.5 and 3 g/l) on some morphophysiological and biochemical traits of Rosa hybrida cv. Dolce Vita. Light and nano-chelated potassium treatments have a significant effect on most traits measured in the present study. According to the results, the use of red light and nano-chelated potassium in rose cultivation improved the quality characteristics and increased vase life. The highest fresh and dry weight of flowering branch and plant height was observed in red light treatment and the concentration of 3 g/l nano-chelated potassium. Biochemical parameters such as phenolic compounds, leaf and petal flavonoids, petal anthocyanin content, antioxidant capacity and vase life were also significantly increased under red light and with the concentration of 3 g/l nano-chelated potassium compared to the control. In general, it can be said that the use of red light and a concentration of 3 g/l nano-chelated potassium, can be effective in improving the quality of rose flowers, especially in low light condition.

A cytosolic bifunctional geranyl/farnesyl diphosphate synthase provides MVA-derived GPP for geraniol biosynthesis in rose flowers.

Geraniol derived from essential oils of various plant species is widely used in the cosmetic and perfume industries. It is also an essential trait of the pleasant smell of rose flowers. In contrast to other monoterpenes which are produced in plastids via the methyl erythritol phosphate pathway, geraniol biosynthesis in roses relies on cytosolic NUDX1 hydrolase which dephosphorylates geranyl diphosphate (GPP). However, the metabolic origin of cytosolic GPP remains unknown. By feeding Rosa chinensis "Old Blush" flowers with pathway-specific precursors and inhibitors, combined with metabolic profiling and functional characterization of enzymes in vitro and in planta, we show that geraniol is synthesized through the cytosolic mevalonate (MVA) pathway by a bifunctional geranyl/farnesyl diphosphate synthase, RcG/FPPS1, producing both GPP and farnesyl diphosphate (FPP). The downregulation and overexpression of RcG/FPPS1 in rose petals affected not only geraniol and germacrene D emissions but also dihydro-ß-ionol, the latter due to metabolic cross talk of RcG/FPPS1-dependent isoprenoid intermediates trafficking from the cytosol to plastids. Phylogenetic analysis together with functional characterization of G/FPPS orthologs revealed that the G/FPPS activity is conserved among Rosaceae species. Site-directed mutagenesis and molecular dynamic simulations enabled to identify two conserved amino acids that evolved from ancestral FPPSs and contribute to GPP/FPP product specificity. Overall, this study elucidates the origin of the cytosolic GPP for NUDX1-dependent geraniol production, provides insights into the emergence of the RcG/FPPS1 GPPS activity from the ancestral FPPSs, and shows that RcG/FPPS1 plays a key role in the biosynthesis of volatile terpenoid compounds in rose flowers.

Phenotyping floral traits and essential oil profiling revealed considerable variations in clonal selections of damask rose (Rosa damascena Mill.).

Damask rose (Rosa damascena Mill.) is a high-value aromatic plant species belonging to the family Rosaceae. It is being cultivated throughout the world for rose essential oil production. Besides its higher demand in the aromatic and cosmetic industry, the essential oil obtained has many pharmacological and cytotoxic activities. The primary concern of growers with the available varieties of damask rose is short flowering duration, low essential oil content and unstable yield. Thus, there is a requirement for developing new stable varieties with higher flower yield and essential oil content. The present study evaluated the variations in the flower yield parameters, essential oil content, and essential oil compounds in different clonal selections of damask rose. These clonal selections have been developed through a half-sib progeny approach from commercially available varieties 'Jwala' and 'Himroz.' The fresh flower yield varied from 629.57 to 965.7 g per plant, while the essential oil content ranged from 0.030-0.045% among the clonal selections. The essential oil profiling via gas chromatography-mass spectrometry revealed significant variations in the essential oil compounds. Acyclic monoterpene alcohols citronellol (20.35-44.75%) and geraniol (15.63-27.76%) were highest, followed by long-chain hydrocarbons, i.e., nonadecane (13.02-28.78%). The clonal selection CSIR-IHBT-RD-04 was unique in terms of the highest citronellol content (44.75%) and citronellol/geraniol (C/G) ratio of 1.93%. This selection has the potential use as a parental line in future genetic improvement programs of damask rose to achieve higher yield and better quality of rose essential oil.

Resequencing of Rosa rugosa accessions revealed the history of population dynamics, breed origin, and domestication pathways.

BACKGROUND: Rosa rugosa is a shrub that originated in China and has economic and ecological value. However, during the development of R. rugosa, the genetic background was chaotic, and the genetic structure among different wild populations was unclear, as well as wild and cultivated accessions. Here, we report whole-genome resequencing of wild and cultivated R. rugosa accessions. RESULTS: A total of 19,041,284 SNPs were identified in 188 R. rugosa accessions and 3 R. chinensis accessions by resequencing. Population genetic analysis revealed that cultivated and wild groups were separated very early. All R. rugosa accessions were divided into 8 categories based on genetic structure: (1) Weihai, Yantai, and Liaoning category, (2) Jilin category, and (3) Hammonasset category (above three are wild); (4) traditional varieties, (5) hybrids between R. rugosa and R. chinensis, (6) Zizhi Rose, (7) Kushui Rose, (8) hybrids between R. rugosa and R. multiflora. We found that the heterozygosity and genetic diversity of wild accessions were generally lower than those of cultivated individuals. The genes that were selected during cultivation were identified, and it was found that these genes were mainly related to environmental adaptation and growth. CONCLUSIONS: The Jilin population was the oldest population and later migrated to Liaoning and then migrated to Yantai and Weihai by sea regression in the Bohai Basin. The Hammonasset naturalized population probably originated from the Jilin population and then experienced separate differentiation. The long-term asexual reproduction pattern of R. rugosa decreased genetic diversity in the wild population. During R. rugosa cultivation, the ancestors of the Jilin population were involved in breeding traditional varieties, after which almost no wild individuals were engaged in breeding. However, in recent decades, cross breeding of R. rugosa started the utilization of wild germplasms. In comparison, some other species play important roles in variety formation. Few genes related to economic traits were selected, suggesting no directional domestication in the R. rugosa cultivation process.

Vasorelaxant property of 2-phenyl ethyl alcohol isolated from the spent floral distillate of damask rose (Rosa damascena Mill.) and its possible mechanism.

ETHNOBOTANICAL RELEVANCE: Rosa damascena Mill. (Rosaceae), commonly known as damask rose, is an ancient medicinal and perfumery plant used in Traditional Unani Medicine due to various therapeutic effects, including cardiovascular benefits. AIM OF THE STUDY: This study aimed to evaluate the vasorelaxant effect of the 2-phenyl ethyl alcohol (PEA) isolated from the spent flowers of R. damascena which remain after the extraction of essential oil. MATERIALS AND METHODS: The freshly collected flowers of R. damascena were hydro-distilled in a Clevenger's type apparatus to extract the rose essential oil (REO). After removing the REO, the spent-flower hydro-distillate was collected and extracted with organic solvents to yield a spent-flower hydro-distillate extract (SFHE), which was further purified by column chromatography. The SFHE and its isolate were characterized by gas chromatography (GC-FID), gas chromatography-mass spectrometry (GC-MS), and nuclear magnetic resonance (NMR) techniques. The PEA, isolated from SFHE, was evaluated for vasorelaxation response in conduit blood vessels like rat aorta and resistant vessels like mesenteric artery. The preliminary screening of PEA was done in aortic preparation pre-constricted with phenylephrine/U46619. Further, a concentration-dependent relaxation response to PEA has been elicited in both endothelium-intact and endothelium-denuded arterial rings, and the mode of action was explored. RESULTS: The SFHE revealed the presence of PEA as the main constituent (89.36%), which was further purified by column chromatography to a purity of 95.0%. The PEA exhibited potent vasorelaxation response both in conduit vessels like the rat aorta and resistance vessels like the mesenteric artery. The relaxation response is mediated without any involvement of vascular endothelium. Further, TEA sensitive BKCa channel was found to be the major target for PEA-induced relaxation response in these blood vessels. CONCLUSIONS: The spent flowers of R. damascena, which remain after the extraction of REO, could be used to extract PEA. The PEA possessed marked vasorelaxation properties in both aorta and mesenteric artery and showed promise for development into an herbal product against hypertension.

Effects of walnut/Rosa roxburghii compound planting on growth, fruit yield, quality of Rosa roxburghii and soil properties.

Walnut and Rosa roxburghii are important arbor and shrub fruit trees cultivated in the southwest mountainous area of China. Furthermore, those two species are compound cultivated in this area. In this study, we investigated the growth, yield, fruit quality, photosynthesis, and soil fertility of R. roxburghii in a 7-year typical 'Qianhe 7'/ 'Guinong 5' compound planting pattern in Guizhou. The results showed that compared with the monoculture, photosynthetic pigment content and photosynthetic rate of R. roxburghii leaves were significantly lower in the compound plantation. The growth and yield of R. roxburghii decreased significantly, with a 77.7% reduction of yield. Fruit quality of R. roxburghii was improved. The content of ascorbic acid (Vc), total phenol, carbohydrate, K, Ca, Mg, Fe, Mn, Zn, and other substances increased significantly. Fruit Vc and Mn content increased by 34.1% and 64.1%, respectively. The contents of total N, available N and K in the soil increased by 45.8%, 34.8% and 67.8%, respectively. The abundance of soil microorganisms and functional bacteria increased significantly, with the increase of bacteria and fungi being more than 36.0%. The increase of potassium bacteria and nitrogen fixing bacteria was 71.3% and 124.8%, respectively. However, the contents of organic matter, carbon-nitrogen ratio, total P, total K, available mineral nutrient (P, Ca, Mg, Fe, Mn, Cu, Zn) contents decreased. While the activities of soil urease and catalase were increased, the activities of other soil enzymes (sucrase, cellulase, protease, phosphatase) were significantly reduced. In summary, with continuous growth of walnuts in the walnut/R. roxburghii compound plantation, there was obvious shade and soil fertility competition for R. roxburghii, which affected its yield, but had a improvement effect on fruit quality.

Assessment of Bioactive Phytochemicals and Utilization of Rosa canina Fruit Extract as a Novel Natural Antioxidant for Mayonnaise.

The oxidation of food emulsions causes rancidity, which reduces their shelf life. To prevent rancidity, synthetic antioxidants are widely used in the food industry. However, due to their potential health risks, researchers are exploring natural alternatives. This study aimed to investigate whether Rosa canina fruit extract (RCFE) could be used as a natural antioxidant to extend the shelf life of mayonnaise. Mayonnaise containing varying concentrations of RCFE [0.125% (T1), 0.25% (T2), 0.50% (T3), 0.75% (T4)] was compared to a mayonnaise control sample (C1) and a mayonnaise sample containing 0.02% BHT (C2) for 60 days of storage at 4 °C. RCFE was found to have high levels of total phenols content (52.06 ± 1.14 mg GAE g-1), total flavonoids content (26.31 ± 1.03 mg QE g-1), and free radical scavenging activity. The GC-MS analysis of RCFE revealed 39 different peaks, whereas the HPLC analysis showed the presence of 13 polyphenolic compounds in RCFE. The pH values of T2, T3, and T4 mayonnaise samples substantially declined as storage progressed; however, the reduction was less than that of C1 and C2. After 60 days, mayonnaise samples T2, T3, and T4 had greatly reduced peroxide and free fatty acid levels compared to C1 and C2. The mayonnaise enriched with RCFE (T3 and T4) had the most potent antioxidative ability and the lowest value of lipid hydroperoxides (peroxide value, POV) and the lowest value of thiobarbituric-acid-reactive substances (TBARS). The sensory evaluation revealed that the T3 sample exhibited the highest overall acceptability. In conclusion, this study recommends that RCFE could be used as a natural preservative to enhance the shelf life of functional foods.

Bioactive Compounds and Antioxidant Activity in the Fruit of Rosehip (Rosa canina L. and Rosa rubiginosa L.).

Rosehips (Rosa spp., Rosaceae) are wild rose bushes with more than 100 species. Its fruits vary in colour and size, depending on the species, and are recognised for their nutritional characteristics. Ten samples of Rosa canina L. and Rosa rubiginosa L. fruits were collected at different geographical points from Southern Chile. Nutrients such as crude protein and minerals and functional properties such as phenolic compounds, ascorbic acid, and also antioxidant activities were evaluated by HPLC-DAD-ESI-MS/MS. The results revealed a high content of bioactive compounds, primarily ascorbic acid (6.0 to 8.2 mg g-1 fresh weight (FW)), flavonols (427.9 ± 0.4 µg g-1 FW) and antioxidant activity. We established a relationship between the antioxidant activity using Trolox equivalent antioxidant capacity (TEAC), cupric reducing antioxidant capacity (CUPRAC) and 2,2-diphenyl radical (DPPH) methods and the concentration of uncoloured compounds, such as flavonols and catechin. This antioxidant activity was primarily associated with the samples from Gorbea, Lonquimay, Loncoche, and Villarrica localities, and all of them were of the species Rosa rubiginosa L. The results here obtained represent novel information of rosehip fruits. In this sense, the reported information about compounds and antioxidant activities in rosehip fruits allowed us to continue new lines of research in relation to the potential formulation of new functional foods and also in the treatment and/or prevention of some diseases.

Quality analysis and geographical origin identification of Rosa roxburghii Tratt from three regions based on Fourier transform infrared spectroscopy.

The study aimed to provide new information of Rosa roxburghii Tratt (RRT) for the production of functional foods and distinguish the geographical origins of RRT. The nutritional components of RRT from three regions in China, such as vitamin C, polysaccharides, total flavonoids, and total phenolics, and their antioxidant activities were analyzed by one-way ANOVA. The results of Fourier transform infrared spectroscopy (FT-IR) combined with principal component analysis (PCA), stepwise linear discriminant analysis (SLDA), k-nearest neighbor (k-NN), and support vector machine (SVM) were used to establish discriminant models to identify the geographical origin of RRT. The results of one-way ANOVA showed that the contents of some nutrients and antioxidant activity were significantly different among RRT from different regions and their FT-IR spectra also showed significant differences. The characteristic fingerprint bands of FT-IR (1679-1618 cm-1and 1520-900 cm-1) closely related to the geographical origins of RRT were screened out. Based on SLDA, a discriminant model was established to realize the classification and identification of RRT from different regions and the correct discrimination rate of the testing sample set obtained with the established model reached 100 %. Geographical factors caused the obvious differences in nutritional components and antioxidant activity in RRT. The characteristic fingerprint bands of RRT obtained with FT-IR could be used to identify the geographical origins of RRT more quickly and accurately.

Development of one step colorimetric RT-LAMP assays for rapid detection of Apple mosaic virus and Prunus necrotic ringspot virus.

Apple mosaic virus (ApMV) and Prunus necrotic ringspot virus (PNRSV), belonging to genus Ilarvirus, cause significant losses to rose and other plants of the family Rosaceae. They are easily transmitted through mechanical or vegetative means. In our previous study, the occurrence of ApMV and PNRSV in rose plants was reported. In this study, as a first step towards the development of a colorimetric Reverse Transcriptase - Loop Mediated Isothermal Amplification (RT-LAMP) assay, two primer sets were designed, each containing six primers (F3, B3, FIP, BIP, LF and LB) targeting the coat protein genes of ApMV and PNRSV. After incubation of RT-LAMP reaction mix at an isothermal temperature (65 °C/30 min), the amplified products were visually confirmed with the nucleic acid intercalation dye SYBR Green I and the indicator dye Hydroxy-Naphthol Blue. The developed assays were virus specific and showed no cross amplification. Their sensitivity was 103 times higher than that of the corresponding RT-PCRs. The LAMP assays developed in this study are inexpensive, rapid and reliable for the early detection of ApMV and PNRSV, and could therefore be used in plant quarantine to control the risk of their spread.

Rosa canina L. improves learning and memory-associated cognitive impairment by regulating glucose levels and reducing hippocampal insulin resistance in high-fat diet/streptozotocin-induced diabetic rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Recent studies claim that Type-2 diabetes mellitus (T2DM) and Alzheimer's disease (AD) overlap in several common pathological pathways which from neuronal damage to impaired memory performance. It is known that the use of Rosa canina L. (R. canina) as medicine in folk medicine dates back to ancient times and is used in the treatment of nervous diseases in Persian medicine. However, the effect of R. canina on diabetes-related cognitive decline and memory impairment has not yet been studied. AIM OF THE STUDY: We evaluated the impact of T2DM on AD-like alterations and examined the molecular mechanism of a possible effect of R. canina on cognitive alterations in diabetic rats. MATERIALS&METHODS: R. canina ethanol extract was obtained by maceration method. This study was performed with male Sprague-Dawley rats fed with a high-fat diet (HFD) for 8 weeks, low-dose streptozotocin (STZ; 35 mg/kg IP) injection for 4 weeks, and R. canina (250 mg/kg; per oral) and metformin (400 mg/kg; per oral) administration for 4 weeks. The weight and blood glucose of rats were measured weekly. To evaluate glucose tolerance area under the curve (AUC) was calculated by performing an oral glucose tolerance test. Then the rats were subjected to behavioural tests, and their hippocampus and cortex tissues were obtained for biochemical and morphological analyses. RESULTS: R. canina could manage glucose responsiveness by reducing post-prandial blood glucose levels, preventing weight loss, and raising serum insulin levels in T2DM-induced rats. Behavioural tests showed that R. canina significantly improves diabetes-related cognitive decline in recall and long-term memory. Treatment with R. canina significantly reversed HFD/STZ-induced increases in insulin, amyloid-ß, amyloid precursor protein levels, and acetylcholinesterase activity in the prefrontal cortex and hippocampus. Furthermore, histological analyzes revealed the protection of R. canina against neuronal disruption in the cortical and hippocampal CA3 region caused by chronic hyperglycemia. CONCLUSION: Analyzed collectively, these results suggest that R. canina can correct T2DM-related cognitive decline may be attributed to insulin pathway modulation, prevention of amyloid deposition, and increased cholinergic transmission.

Transcriptomic-based analysis to identify candidate genes for blue color rose breeding.

KEY MESSAGE: Analysis of the flower color formation mechanism of 'Rhapsody in Blue' by BF and WF transcriptomes reveals that RhF3'H and RhGT74F2 play a key role in flower color formation. Rosa hybrida has colorful flowers and a high ornamental value. Although rose flowers have a wide range of colors, no blue roses exist in nature, and the reason for this is unclear. In this study, the blue-purple petals (BF) of the rose variety 'Rhapsody in Blue' and the white petals (WF) of its natural mutant were subjected to transcriptome analysis to find genes related to the formation of the blue-purple color. The results showed that the anthocyanin content was significantly higher in BF than in WF. A total of 1077 differentially expressed genes (DEGs) were detected by RNA-Seq analysis, of which 555 were up-regulated and 522 were down-regulated in the WF vs. BF petals. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses of the DEGs revealed that a single gene up-regulated in BF was related to multiple metabolic pathways including metabolic process, cellular process, protein-containing complex, etc. Additionally, the transcript levels of most of the structural genes related to anthocyanin synthesis were significantly higher in BF than in WF. Selected genes were analyzed by qRT-PCR and the results were highly consistent with the RNA-Seq results. The functions of RhF3'H and RhGT74F2 were verified by transient overexpression analyses, and the results confirmed that both affect the accumulation of anthocyanins in 'Rhapsody in Blue'. We have obtained comprehensive transcriptome data for the rose variety 'Rhapsody in Blue'. Our results provide new insights into the mechanisms underlying rose color formation and even blue rose formation.

BOX38, a DNA Marker for Selection of Essential Oil Yield of Rosa × rugosa.

Rosa rugosa L. was a famous aromatic plant whose cultivars (Rosa × rugosa) have been widely used in the perfume industry in Asia. The perfume market looks for rose cultivars bearing higher essential oil, while the oil yields of most R. × rugosa have not been evaluated due to limiting conditions, such as insufficient cultivation areas. Here, we tested the yield and the aroma components of essential oil of 19 R. × rugosa. The results indicated that the yields of nerol, citronellol, and geraniol could represent an alternative index of the total yield of essential oil. Sequence syntenic analysis indicated that the Rosa genus specific cis-element Box38 was highly polymorphic. The Box38 region isolation of Rosa × rugosa by flanked primers proved that Box38 repeat number was significantly positively correlated with the essential oil yield of the corresponding cultivar. In the breeding of Rosa × rugosa, six-Box38-repeat could be a robust threshold for selection of high-essential-oil roses. Together, we found that Box38 was a DNA marker for essential oil yield and that it would be helpful in the early selection and breeding of essential oil roses.

Genome-Wide Identification and Expression Analysis of Rosa roxburghii Autophagy-Related Genes in Response to Top-Rot Disease.

Autophagy is a highly conserved process in eukaryotes that degrades and recycles damaged cells in plants and is involved in plant growth, development, senescence, and resistance to external stress. Top-rot disease (TRD) in Rosa roxburghii fruits caused by Colletotrichum fructicola often leads to huge yield losses. However, little information is available about the autophagy underlying the defense response to TRD. Here, we identified a total of 40 R. roxburghii autophagy-related genes (RrATGs), which were highly homologous to Arabidopsis thaliana ATGs. Transcriptomic data show that RrATGs were involved in the development and ripening processes of R. roxburghii fruits. Gene expression patterns in fruits with different degrees of TRD occurrence suggest that several members of the RrATGs family responded to TRD, of which RrATG18e was significantly up-regulated at the initial infection stage of C. fructicola. Furthermore, exogenous calcium (Ca2+) significantly promoted the mRNA accumulation of RrATG18e and fruit resistance to TRD, suggesting that this gene might be involved in the calcium-mediated TRD defense response. This study provided a better understanding of R. roxburghii autophagy-related genes and their potential roles in disease resistance.

Identification and molecular characterization of a novel cytorhabdovirus from rose plants (Rosa chinensis Jacq.).

A novel negative-sense single-stranded RNA virus, tentatively named "rose-associated cytorhabdovirus" (RaCV), was identified by high-throughput sequencing. RaCV is 16,067 nucleotides in length and contains eight open reading frames (ORFs 1-8) encoding a nucleocapsid protein (N), a putative phosphoprotein (P), a putative P3 protein (P3), a putative P4 protein (P4), a putative matrix protein (M), a glycoprotein (G), a putative P7 protein (P7), and an RNA-dependent RNA polymerase (L), respectively. The coding genes are flanked by a 3' leader sequence (228 nt) and a 5' trailer sequence (251 nt) and are separated by conserved intergenic junctions (3'-AUUCUUUUUG(N)nCUN-5'). Phylogenetic analysis showed that RaCV clustered with yerba mate virus A (YmVA) within the cytorhabdovirus clade, and it exhibited low a degree of nt sequence similarity (<40% identity) to other rhabdoviruses. Amino acid sequence comparisons between the putative proteins of RaCV and the corresponding proteins of other cytorhabdoviruses showed that the sequence identity levels were far below the species demarcation cutoff of 80% for cytorhabdoviruses. These results suggest that RaCV should be classified as a new member of the genus Cytorhabdovirus.

Exploring the mechanism of browning of Rosa roxburghii juice based on nontargeted metabolomics.

To explore the mechanism of Rosa roxburghii juice browning, this experiment was based on nontargeted metabolomics to study the effects of browning on the nutrition, flavor, metabolites, and metabolic pathways of R. roxburghii juice before and after storage. The results showed that the total soluble solids, superoxide dismutase (SOD), vitamin C (VC ), total phenol, and total flavonoid of R. roxburghii juice decreased significantly before and after storage. The color difference value ∆E, browning index, and flavor and taste of R. roxburghii juice changed significantly (p < 0.05). A total of 541 metabolites were detected before and after browning of R. roxburghii juice by nontargeted metabolomics, including 435 differential metabolites, of which 221 were upregulated, and 214 were downregulated. The differential metabolites were mainly amino acids and peptides, carbohydrates, and carbohydrate conjugates. There were a total of 76 metabolic pathways enriched by differential metabolites, involving mainly galactose metabolism; alanine, aspartate and glutamate metabolism; and pantothenate and CoA biosynthesis. The experimental results showed that after browning of R. roxburghii juice, VC , total phenol, total flavonoid, and SOD activity were seriously lost, and the flavor deteriorated. The contribution of differential metabolites and metabolic pathways to the browning of R. roxburghii juice was sugar metabolism > amino acid metabolism > ascorbate and aldarate metabolism > phenols.

From UAV to PlanetScope: Upscaling fractional cover of an invasive species Rosa rugosa.

Invasive plant species pose a direct threat to biodiversity and ecosystem services. Among these, Rosa rugosa has had a severe impact on Baltic coastal ecosystems in recent decades. Accurate mapping and monitoring tools are essential to quantify the location and spatial extent of invasive plant species to support eradication programs. In this paper we combined RGB images obtained using an Unoccupied Aerial Vehicle, with multispectral PlanetScope images to map the extent of R. rugosa at seven locations along the Estonian coastline. We used RGB-based vegetation indices and 3D canopy metrics in combination with a random forest algorithm to map R. rugosa thickets, obtaining high mapping accuracies (Sensitivity = 0.92, specificity = 0.96). We then used the R. rugosa presence/absence maps as a training dataset to predict the fractional cover based on multispectral vegetation indices derived from the PlanetScope constellation and an Extreme Gradient Boosting algorithm (XGBoost). The XGBoost algorithm yielded high fractional cover prediction accuracies (RMSE = 0.11, R2 = 0.70). An in-depth accuracy assessment based on site-specific validations revealed notable differences in accuracy between study sites (highest R2 = 0.74, lowest R2 = 0.03). We attribute these differences to the various stages of R. rugosa invasion and the density of thickets. In conclusion, the combination of RGB UAV images and multispectral PlanetScope images is a cost-effective method to map R. rugosa in highly heterogeneous coastal ecosystems. We propose this approach as a valuable tool to extend the highly local geographical scope of UAV assessments into wider areas and regional evaluations.

Geographic isolation and climatic heterogeneity drive population differentiation of Rosa chinensis var. spontanea complex.

Global biodiversity is contracting rapidly due to potent anthropogenic activities and severe climate change. Wild populations of Rosa chinensis var. spontanea and Rosa lucidissima are rare species endemic to China, as well as important germplasm resources for rose breeding. However, these populations are at acute risk of extinction and require urgent action to ensure their preservation. We harnessed 16 microsatellite loci to 44 populations of these species and analysed population structure and differentiation, demographic history, gene flow and barrier effect. In addition, a niche overlap test and potential distribution modelling in different time periods were also carried out. The data indicate that: (1) R. lucidissima cannot be regarded as a separate species from R. chinensis var. spontanea; (2) the Yangtze River and the Wujiang River function as barriers in population structure and differentiation, and precipitation in the coldest quarter may be the key factor for niche divergence of R. chinensis var. spontanea complex; (3) historical gene flow showed a converse tendency to current gene flow, indicating that alternate migration events of R. chinensis var. spontanea complex between south and north were a response to climate oscillations; and (4) extreme climate change will decrease the distribution range of R. chinensis var. spontanea complex, whereas the opposite will occur under a moderate scenario for the future. Our results resolve the relationship between R. chinensis var. spontanea and R. lucidissima, highlight the pivotal roles of geographic isolation and climate heterogeneity in their population differentiation, and provide an important reference for comparable conservation studies on other endangered species.