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Taraxast-19-en-3β-ol (1) and taraxast-19-en-3-one (2) were isolated from the surface lipids of young shoots of Rosa multiflora Thunb. The results provide the first evidence that deprotonation of H-19 can occur to produce the tetra-substituted triterpenes, in addition to the known formation taraxasterol and ϕ-taraxasterol by deprotonation of H-30 and H-21, respectively. Furthermore, taraxast-19(29)-ene-3β,20α-diol (3), which is presumed to be formed from compound 1 was isolated. The structures of the new compounds 1 - 3 with the α-orientation of H-18 were determined by spectroscopic methods including NOE studies. In addition, 19,20-seco-3β-hydroxyursane-19,20-dione (4), a 3β-hydroxy analog of the known 19,20-seco-ursane-3,19,20-trione was isolated. It is of note that compound 4 has the β-orientation of H-18, which is opposite to the α-orientation of H-18 of compounds 1 - 3. [Display omitted] • Triterpenoids produced by elimination of H-19 of taraxasteryl cation were explored. • Taraxast-19-en-3β-ol and taraxast-19-en-3-one were isolated and characterized. • Taraxast-19(29)-en-20β-ol, a metabolite from taraxast-19-en-3β-ol, was isolated. • 19,20-Seco-3β-hydroxyursane-19,20-dione with 18β-H configuration was isolated. [ABSTRACT FROM AUTHOR]

Roses, a popular ornamental crop, often face various abiotic stresses during growth and development, such as cold, drought, and salinity. Rosa multiflora is a commonly used rootstock and exhibits strong resistance to both biotic and abiotic stresses, making it an ideal material for studying mechanisms for resistance. Among the largest plant families, MYB transcription factors play a crucial role in plant abiotic stresses. Our previous research has indicated that RmMYB44 could be involved in the low-temperature response of R. multiflora. This study further investigated RmMYB44, revealing that its expression levels were upregulated in response to chilling, drought, and salt stress. The results suggested its potential role as a key transcription factor in plant resistance to abiotic stresses. Additionally, RmMYB44 encoded a nuclear-localized protein without the self-activating function. The overexpression of RmMYB44 in tobacco plants enhanced the resistance to cold, drought, and salt stresses, as evidenced by the improved growth compared to wild-type (WT) plants under conditions of 4 °C, 30% water-holding capacity, and 200 mM of NaCl, respectively. Moreover, in overexpression tobacco plants, the levels of hydrogen peroxide and malondialdehyde (MDA) were significantly reduced; and the activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT); as well as the proline content and the expression levels of NtPOD, NtCAT, and NtCBF; were significantly elevated under abiotic stresses. We assumed that the resistance to abiotic stress in plants conferred by RmMYB44 was associated with the regulation of cell membrane integrity. This study aimed to elucidate the role of the RmMYB44 gene in the resistance mechanism of R. multiflora against abiotic stress, thereby providing a candidate gene for the molecular breeding of abiotic stress resistance in roses and related species. [ABSTRACT FROM AUTHOR]

Rosa multiflora, originated from East Asia, is one of the original ancestors of modern roses. It is also an important genetic resource and rootstock for rose cultivation. Due to its high resistance and vigorous growth, R. multiflora has become an invasive species in some introduction sites, such as North America. To explore the correlation between the suitable habitat of R. multiflora and climate change, we predicted its potential geographic distribution with an optimized MaxEnt model based on 1246 distribution records and nine bioclimatic variables. The results showed that the mean temperature of the coldest quarter, minimum temperature of the coldest month, precipitation of the warmest quarter, and isothermality were significant bioclimatic variables affecting the potential geographic distribution of R. multiflora. Under current climate conditions, R. multiflora naturally distributed in the plains and hilly areas to the east and south of the Loess Plateau. The distribution pattern in the mid-holocene was similar to its current distribution, but the highly suitable distribution area was in the south of North China Plain, the Sichuan Basin, and parts of the Middle-Lower Yangtze Plain. During the last interglacial, the suitable areas generally contracted southward, while the highly suitable areas significantly expanded and mainly located in the Sichuan Basin, the Middle-Lower Yangtze Plains, the Yunnan-Guizhou Plateau, and the Southeast Hills. Beyond its natural distribution in East Asia, R. multiflora had been introduced and spread to most parts of Europe and the central and eastern United States. The distribution area of R. multiflora would expand under three warming scenarios of different shared socioeconomic pathways (SSP1-2.6, SSP2-4.5, and SSP5-8.5) during 2041-2060 and 2081-2100. Its average distribution center (centroid) would shift towards higher latitude, indicating that the distribution of R. multiflora was closely related to climate change and that global warming might lead to an expansion of its distribution area. These results would improve our understanding of the ecological adaptability of R. multiflora, facilitate the predicting of its future distribution, and provide a theoretical basis for monitoring and early warning measures following its introduction. [ABSTRACT FROM AUTHOR]

Ethylene‐responsive factors (ERFs) participate in a wide range of physiological and biological processes. However, many of the functions of ERFs in cold stress responses remain unclear. We, therefore, characterised the cold responses of RmERF54 in Rosa multiflora, a rose‐related cold‐tolerant species. Overexpression of RmERF54, which is a nuclear transcription factor, increases the cold resistance of transgenic tobacco and rose somatic embryos. In contrast, virus‐induced gene silencing (VIGS) of RmERF54 increased cold susceptibility of R. multiflora. The overexpression of RmERF54 resulted in extensive transcriptional reprogramming of stress response and antioxidant enzyme systems. Of these, the levels of transcripts encoding the PODP7 peroxidase and the cold‐related COR47 protein showed the largest increases in the somatic embryos with ectopic expression of RmERF54. RmERF54 binds to the promoters of the RmPODP7 and RmCOR47 genes and activates expression. RmERF54‐overexpressing lines had higher antioxidant enzyme activities and considerably lower levels of reactive oxygen species. Opposite effects on these parameters were observed in the VIGS plants. RmERF54 was identified as a target of Dehydration‐Responsive‐Element‐Binding factor (RmDREB1E). Taken together, provide new information concerning the molecular mechanisms by which RmERF54 regulates cold tolerance. Summary statement: RmDREB1E‐RmERF54 module play a positive role in cold stress, which might be, at least in part, modulation of RmCOR47 and RmPODP7 expression. [ABSTRACT FROM AUTHOR]

Obesity is one of the major risk factors for metabolic diseases worldwide. This study examined the effects of YC-1102, an extract derived from the roots of Rosa multiflora, on 3T3-L1 preadipocytes and high-fat diet (HFD)-induced obese mice. In vivo experiments involved the oral administration of YC-1102 (100, 150, and 200 mg/kg body weight) daily to mice for eight weeks. YC-1102 was found to downregulate the expressions of PPARγ and C/EBPα during adipogenesis, inhibiting adipocyte differentiation and upregulating the expression of PGC-1α for energy metabolism to enhance mitochondrial biogenesis and fatty acid oxidation. It has been shown that daily administration of YC-1102 to mice receiving a HFD prevented an increase in body weight and the accumulation of body fat. YC-1102 administration also reduced TG, TC, and LDL cholesterol levels, as well as glucose and leptin levels, and increased adiponectin levels, thus effectively inhibiting the metabolism of lipids. YC-1102-treated mice showed significant reductions in the mRNA expression of PPARγ and C/EBPα. The levels of PGC-1α involved in energy metabolism increased significantly in the YC-1102-treated mice when compared to the HFD-treated mice. According to the findings of this study, YC-1102 has a dual mechanism that reduces transcription factors that promote the differentiation of adipocytes and increases transcription factors that promote energy consumption.

Invasive plants often alter ecosystem function and processes, especially soil N cycling. In eastern United States forests, the shrub Rosa multiflora ("rose") is a dominant invader, yet potential effects on N cycling are poorly understood. Moreover, invasive plant management can impact soil N cycling by decreasing plant N uptake and disturbing the soil. The objectives of this study were to evaluate N cycling along a gradient of rose invasion (observational) and investigate potential changes to N cycling (manipulative) under four different management strategies: (1) do nothing (the control), (2) invasive plant removal, (3) removal followed by native seed mix addition, (4) removal, native seed mix, and chipped rose stem addition. We selected three forest sites experiencing a Low, Medium, or High amount of shrub invasion, and measured N cycling in the early (June) and late (September) growing seasons. We found N was immobilized in June and mineralized in September. One year after experimental management, removal alone had no effect on N cycling compared to control plots, but addition of native seed mix and chipped stems reduced early-season nitrification in our Medium invasion site. Our findings suggest that rose invasion may increase N cycling rates when soils are dry, which may occur more frequently with future climate change. In addition, N cycling responds differentially to management in the year following invasive plant removal, but most noticeably under moderate rose invasion. [ABSTRACT FROM AUTHOR]

Roses, a popular ornamental crop, often face various abiotic stresses during growth and development, such as cold, drought, and salinity. Rosa multiflora is a commonly used rootstock and exhibits strong resistance to both biotic and abiotic stresses, making it an ideal material for studying mechanisms for resistance. Among the largest plant families, MYB transcription factors play a crucial role in plant abiotic stresses. Our previous research has indicated that RmMYB44 could be involved in the low-temperature response of R. multiflora. This study further investigated RmMYB44, revealing that its expression levels were upregulated in response to chilling, drought, and salt stress. The results suggested its potential role as a key transcription factor in plant resistance to abiotic stresses. Additionally, RmMYB44 encoded a nuclear-localized protein without the self-activating function. The overexpression of RmMYB44 in tobacco plants enhanced the resistance to cold, drought, and salt stresses, as evidenced by the improved growth compared to wild-type (WT) plants under conditions of 4 °C, 30% water-holding capacity, and 200 mM of NaCl, respectively. Moreover, in overexpression tobacco plants, the levels of hydrogen peroxide and malondialdehyde (MDA) were significantly reduced; and the activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT); as well as the proline content and the expression levels of NtPOD, NtCAT, and NtCBF; were significantly elevated under abiotic stresses. We assumed that the resistance to abiotic stress in plants conferred by RmMYB44 was associated with the regulation of cell membrane integrity. This study aimed to elucidate the role of the RmMYB44 gene in the resistance mechanism of R. multiflora against abiotic stress, thereby providing a candidate gene for the molecular breeding of abiotic stress resistance in roses and related species.

High salinity restricts plant growth and geographic distribution. Plant intracellular Na+/H+ (NHX) antiporters have critical roles in plant development and stress response. However, the molecular functions of RmNHXs in Rosa multiflora remain unclear. In this study, we identified 11 putative RmNHXs in R. multiflora according to the genome-wide analysis. The RmNHXs were classified into three classes. Most of the RmNHXs were responsive to salt stress, with the greatest upregulation being observed in RmNHX2. RmNHX2 was localized at the tonoplast. RmNHX2 overexpression resulted in the enhanced salt tolerance in tobacco, whereas virus-induced gene silencing (VIGS) of RmNHX2 in R. multiflora elevated salt susceptibility. Under salt treatment, the transgenic tobaccos achieved less reactive oxygen species (ROS) accumulation and higher activities of antioxidant enzymes, which complied with the upregulated expressions of antioxidant genes. Moreover, RmNHX2-overexpression lines had a lower level of Na+, a higher level of K+, and a lower Na/K ratio. In contrast to the mentioned, VIGS of RmNHX2 in R. multiflora exhibited the opposite phenotype, accompanied by a compromised salt tolerance. Regarded together, these results demonstrate that RmNHX2 enhances plant salt tolerance by maintaining proper ion homeostasis, as well as by accelerating ROS scavenging. [ABSTRACT FROM AUTHOR]

Globally, temperate deciduous forests are threatened by invasion of non‐native (exotic) plant species. In the eastern United States, Rosa multiflora is a dominant shrub invader in forests, which often forms dense thickets that reduce sunlight availability in the understory, where decreased native plant diversity and abundance are observed. Management and restoration are difficult but desirable, especially when invasion intensity is still low. Few studies have examined the relative success of different management strategies under varying invasion intensities. Our study objectives were to conduct a R. multiflora removal experiment in three forest sites experiencing different invasion intensities and to restore native plant biodiversity while preventing secondary invasion. We utilized three management strategies: invasive plant removal, removal followed by native seed addition, and removal plus native seed and mulched invasive stem addition. We investigated the similarity between seed bank species composition and existing vegetation before and after removal to assess the potential for passive restoration. Two seasons after removal, we found that simply removing roses increased native species richness, native floristic quality assessment (FQAIN), and native shrub abundance in our medium invasion site, and total species richness in our low and medium invasion sites. Compared to removal alone, native seed addition, with and without mulch addition, resulted in larger native and total species richness and FQAIN increases at all sites, larger increases in native shrub abundance and exotic species richness in our medium invasion site, and larger reductions in exotic and total shrub abundance in our low and medium invasion sites. Following removal, species similarity between the seed bank and vegetation improved for all three sites. Our results indicate that removal of R. multiflora alone increased native plant biodiversity in the medium invasion scenario, but the seed bank may not provide a large native species pool. Additional management strategies lead to improved outcomes, especially in our most invaded forest, demonstrating the need to conduct multiple plant removal treatments across forests with varying site conditions and plant invasion intensity to improve management recommendations. [ABSTRACT FROM AUTHOR]

Abstract Globally, temperate deciduous forests are threatened by invasion of non‐native (exotic) plant species. In the eastern United States, Rosa multiflora is a dominant shrub invader in forests, which often forms dense thickets that reduce sunlight availability in the understory, where decreased native plant diversity and abundance are observed. Management and restoration are difficult but desirable, especially when invasion intensity is still low. Few studies have examined the relative success of different management strategies under varying invasion intensities. Our study objectives were to conduct a R. multiflora removal experiment in three forest sites experiencing different invasion intensities and to restore native plant biodiversity while preventing secondary invasion. We utilized three management strategies: invasive plant removal, removal followed by native seed addition, and removal plus native seed and mulched invasive stem addition. We investigated the similarity between seed bank species composition and existing vegetation before and after removal to assess the potential for passive restoration. Two seasons after removal, we found that simply removing roses increased native species richness, native floristic quality assessment (FQAIN), and native shrub abundance in our medium invasion site, and total species richness in our low and medium invasion sites. Compared to removal alone, native seed addition, with and without mulch addition, resulted in larger native and total species richness and FQAIN increases at all sites, larger increases in native shrub abundance and exotic species richness in our medium invasion site, and larger reductions in exotic and total shrub abundance in our low and medium invasion sites. Following removal, species similarity between the seed bank and vegetation improved for all three sites. Our results indicate that removal of R. multiflora alone increased native plant biodiversity in the medium invasion scenario, but the seed bank may not provide a large native species pool. Additional management strategies lead to improved outcomes, especially in our most invaded forest, demonstrating the need to conduct multiple plant removal treatments across forests with varying site conditions and plant invasion intensity to improve management recommendations.

Розглянуто вміст, компонентний склад та кількісне співвідношення алканів, що входять до складу воску пелюсток рослин представників роду Rosa L., що культивуються у Північному Лісостепу України. Актуальність і перспективність дослідження обраної проблеми зумовлена тим, що вихідні дані видів, що застосовуються в інтродукційній, селекційно-генетичній роботі, впливають на прогнозовану адаптацію та стійкість рослин. Дані про фітохімічний склад рослин необхідні для розуміння функції, яку відіграють сполуки у рослинах і мають важливе науково-практичне значення. Стійкість рослин, зокрема генеративних органів, визначається багатьма властивостями кутикули, що містить вторинні метаболіти. Важливі функції поверхневих восків доповнюються здатністю рослин утримувати та накопичувати тверді частинки забруднювальних повітря речовин у міських фітоценозах, яка варіює залежно від виду рослин, але у всіх видів позитивно корелює з масою кутикулярного воску. Нерозгалужені довголанцюгові алкани забезпечують гідрофобні властивості листкових восків і виступають первинним бар'єром рослин від зовнішніх умов середовища, захищаючи листки від втрат вологи шляхом транспірації. Види роду Rosa L. є багатим генетичним потенціалом дослідження, оскільки видовий склад роду становить 180-400 видів, згідно з різними джерелами. Стійкість природних видів зумовлена еволюційним відбором. Вивчення п'яти видів роду Rosa L.: R. multiflora Thunb., R. spinosissima L., R. canina L., R. centifolia L., R. rugosa Thunb здійснювали на базі колекційного фонду Національного ботанічного саду ім. М. М. Гришка НАН України. Ці види належать до трьох підродів і п'яти секцій: Підрід Stylorhodon Dumortier, Секція Synstylae DC. – R. multiflora Thunb.; Підрід Cynorhodon Dumortier, Секція Caninae Crep., Підсекція Eucaninae Crep. – R. canina L.; Секція Rugosa Chrshan. – R. rugosa Thunb.; Секція Gallicanae DC. – R. centifolia L.; Підрід Chamaerhodon Dumortier., Секція Pimpinellifoliae DC. – R. spinosissima L. Органічні леткі речовини виділяли традиційним методом – паровою дистиляцією. Леткі компоненти визначали з використанням системи ГХ-МСД Agilent Technologies 6890/5973. Для ідентифікації компонентів використано мас-спектральні бібліотеки NIST 05 та WILEY 2007 із загальною кількістю спектрів понад 470000 у поєднанні з програмами ідентифікації AMDIS та NIST. Усього визначено 28 компонентів, які належали до середніх або рідких (С10-С15) та вищих або твердих (С16-С34) алканів. Найбільший вміст алканів відзначено у пелюстках видів R. multiflora (72,06 %) та R. canina (87,50 %), середня кількість – R. centifolia (57,18 %), невисоким вмістом відзначилися пелюстки видів R. rugosa (14,58 %) та R. spinosissima (16,84 %). Для всіх досліджених видів шипшини характерна наявність насичених нерозгалужених вуглеводнів, таких як декан, тетрадекан, пентадекан, гексадекан, гептадекан, октадекан, нанодекан, генейкозан, трикозан, тетракозан, пентакозан, гептокозан, нанокозан, гентріаконтан, що показує їхню виняткову роль у складі восків пелюсток квіток рослин.

Powdery mildew disease caused by Podosphaerapannosa is the most widespread disease in global cut-rose production, as well as a major disease in garden and pot roses. In this study, the powdery mildew resistance of different wild rose varieties was evaluated. Rose varieties with high resistance and high sensitivity were used for cytological observation and transcriptome and expression profile analyses to study changes at the morphological and molecular levels during the interaction between Rosa multiflora and P. pannosa. There were significant differences in powdery mildew resistance among three R. multiflora plants; R. multiflora '13' had high resistance, while R. multiflora '4' and '1' had high susceptibility. Cytological observations showed that in susceptible plants, 96 and 144 h after inoculation, hyphae were observed in infected leaves; hyphae infected the leaf tissue through the stoma of the lower epidermis, while papillae were formed on the upper epidermis of susceptible leaf tissue. Gene ontology enrichment analysis showed that the differentially expressed genes that were significantly enriched in biological process functions were related to the secondary metabolic process, the most significantly enriched cellular component function was cell wall, and the most significantly enriched molecular function was chitin binding. Changes in the transcript levels of important defense-related genes were analyzed. The results showed that chitinase may have played an important role in the interactions between resistant R. multiflora and P. pannosa. Jasmonic acid and ethylene (JA/ET) signaling pathways might be triggered in the interaction between susceptible R. multiflora and P. pannosa. In the resistant R. multiflora, the salicylic acid (SA) signaling pathway was induced earlier. Between susceptible plants and resistant plants, key phenylpropanoid pathway genes were induced and upregulated after P. pannosa inoculation, demonstrating that the phenylpropanoid pathway and secondary metabolites may play important and active roles in R. multiflora defense against powdery mildew infection. [ABSTRACT FROM AUTHOR]

High salinity restricts plant growth and geographic distribution. Plant intracellular Na+/H+ (NHX) antiporters have critical roles in plant development and stress response. However, the molecular functions of RmNHXs in Rosa multiflora remain unclear. In this study, we identified 11 putative RmNHXs in R. multiflora according to the genome-wide analysis. The RmNHXs were classified into three classes. Most of the RmNHXs were responsive to salt stress, with the greatest upregulation being observed in RmNHX2. RmNHX2 was localized at the tonoplast. RmNHX2 overexpression resulted in the enhanced salt tolerance in tobacco, whereas virus-induced gene silencing (VIGS) of RmNHX2 in R. multiflora elevated salt susceptibility. Under salt treatment, the transgenic tobaccos achieved less reactive oxygen species (ROS) accumulation and higher activities of antioxidant enzymes, which complied with the upregulated expressions of antioxidant genes. Moreover, RmNHX2-overexpression lines had a lower level of Na+, a higher level of K+, and a lower Na/K ratio. In contrast to the mentioned, VIGS of RmNHX2 in R. multiflora exhibited the opposite phenotype, accompanied by a compromised salt tolerance. Regarded together, these results demonstrate that RmNHX2 enhances plant salt tolerance by maintaining proper ion homeostasis, as well as by accelerating ROS scavenging.

Rosa multiflora , originated from East Asia, is one of the original ancestors of modern roses. It is also an important genetic resource and rootstock for rose cultivation. Due to its high resistance and vigorous growth, R. multiflora has become an invasive species in some introduction sites, such as North America. To explore the correlation between the suitable habitat of R. multiflora and climate change, we predicted its potential geographic distribution with an optimized MaxEnt model based on 1246 distribution records and nine bioclimatic variables. The results showed that the mean temperature of the coldest quarter, minimum temperature of the coldest month, precipitation of the warmest quarter, and isothermality were significant bioclimatic variables affecting the potential geographic distribution of R. multiflora. Under current climate conditions, R. multiflora naturally distributed in the plains and hilly areas to the east and south of the Loess Plateau. The distribution pattern in the mid-holocene was similar to its current distribution, but the highly suitable distribution area was in the south of North China Plain, the Sichuan Basin, and parts of the Middle-Lower Yangtze Plain. During the last interglacial, the suitable areas generally contrac-ted southward, while the highly suitable areas significantly expanded and mainly located in the Sichuan Basin, the Middle-Lower Yangtze Plains, the Yunnan-Guizhou Plateau, and the Southeast Hills. Beyond its natural distribution in East Asia, R. multiflora had been introduced and spread to most parts of Europe and the central and eastern United States. The distribution area of R. multiflora would expand under three warming scenarios of different shared socioeconomic pathways (SSP1-2.6, SSP2-4.5, and SSP5-8.5) during 2041-2060 and 2081-2100. Its average distribution center (centroid) would shift towards higher latitude, indicating that the distribution of R. multiflora was closely related to climate change and that global warming might lead to an expansion of its distribution area. These results would improve our understanding of the ecological adaptability of R. multiflora , facilitate the predicting of its future distribution, and provide a theoretical basis for monitoring and early warning measures following its introduction.

A sudden cooling in the early spring or late autumn negatively impacts the plant growth and development. Although a number of studies have characterized the role of the transcription factors (TFs) of plant R2R3-myeloblastosis (R2R3-MYB) in response to biotic and abiotic stress, plant growth, and primary and specific metabolisms, much less is known about their role in Rosa multiflora under chilling stress. In the present study, RmMYB108, which encodes a nuclear-localized R2R3-MYB TF with a self-activation activity, was identified based on the earlier published RNA-seq data of R. multiflora plants exposed to short-term low-temperature stress and also on the results of prediction of the gene function referring Arabidopsis. The RmMYB108 gene was induced by stress due to chilling, salt, and drought and was expressed in higher levels in the roots than in the leaves. The heterologous expression of RmMYB108 in Arabidopsis thaliana significantly enhanced the tolerance of transgenic plants to freezing, water deficit, and high salinity, enabling higher survival and growth rates, earlier flowering and silique formation, and better seed quantity and quality compared with the wild-type (WT) plants. When exposed to a continuous low-temperature stress at 4°C, transgenic Arabidopsis lines–overexpressing RmMYB108 showed higher activities of superoxide dismutase and peroxidase, lower relative conductivity, and lower malondialdehyde content than the WT. Moreover, the initial fluorescence (Fo) and maximum photosynthetic efficiency of photosystem II (Fv/Fm) changed more dramatically in the WT than in transgenic plants. Furthermore, the expression levels of cold-related genes involved in the ICE1 (Inducer of CBF expression 1)-CBFs (C-repeat binding factors)-CORs (Cold regulated genes) cascade were higher in the overexpression lines than in the WT. These results suggest that RmMYB108 was positively involved in the tolerance responses when R. multiflora was exposed to challenges against cold, freeze, salt, or drought and improved the cold tolerance of transgenic Arabidopsis by reducing plant damage and promoting plant growth.

A sudden cooling in the early spring or late autumn negatively impacts the plant growth and development. Although a number of studies have characterized the role of the transcription factors (TFs) of plant R2R3-myeloblastosis (R2R3-MYB) in response to biotic and abiotic stress, plant growth, and primary and specific metabolisms, much less is known about their role in Rosa multiflora under chilling stress. In the present study, RmMYB108 , which encodes a nuclear-localized R2R3-MYB TF with a self-activation activity, was identified based on the earlier published RNA-seq data of R. multiflora plants exposed to short-term low-temperature stress and also on the results of prediction of the gene function referring Arabidopsis. The RmMYB108 gene was induced by stress due to chilling, salt, and drought and was expressed in higher levels in the roots than in the leaves. The heterologous expression of RmMYB108 in Arabidopsis thaliana significantly enhanced the tolerance of transgenic plants to freezing, water deficit, and high salinity, enabling higher survival and growth rates, earlier flowering and silique formation, and better seed quantity and quality compared with the wild-type (WT) plants. When exposed to a continuous low-temperature stress at 4°C, transgenic Arabidopsis lines–overexpressing RmMYB108 showed higher activities of superoxide dismutase and peroxidase, lower relative conductivity, and lower malondialdehyde content than the WT. Moreover, the initial fluorescence (F o) and maximum photosynthetic efficiency of photosystem II (F v/ F m) changed more dramatically in the WT than in transgenic plants. Furthermore, the expression levels of cold-related genes involved in the ICE1 (Inducer of CBF expression 1)-CBFs (C-repeat binding factors)-CORs (Cold regulated genes) cascade were higher in the overexpression lines than in the WT. These results suggest that RmMYB108 was positively involved in the tolerance responses when R. multiflora was exposed to challenges against cold, freeze, salt, or drought and improved the cold tolerance of transgenic Arabidopsis by reducing plant damage and promoting plant growth. [ABSTRACT FROM AUTHOR]

Invasion of non‐native shrubs comprises a serious economic and ecological problem in North American forests. Prescribed grazing by goats may offer an effective alternative to traditional methods of control, but has received little study in forest settings. In a 5‐year field experiment, we varied the stocking of goats and number of grazing periods to determine effects of prescribed grazing on both invasive shrubs and native plant species. Specifically, we examined how varied stocking levels and grazing periods affect: (1) the cover and height of invasive shrub and native woody species (2) the cover and diversity of herbaceous species, and (3) the density of native tree seedlings. Data were analyzed with linear mixed‐effects models. We found that prescribed grazing by goats significantly reduced the cover and height of invasive shrubs, regardless of goat stocking or duration. Generally, the greatest reductions in invasive shrub cover occurred in treatments with two grazing periods, regardless of goat stocking. While we observed mostly neutral or positive effects on the herbaceous layer, all grazing treatments reduced the cover and height of native understory woody species. While changes were not significant, we observed a general decline in the aggregate height of native tree species regeneration. Our results suggest that prescribed grazing by goats provides an effective and environmentally friendly treatment for heavy invasions of non‐native shrubs such as Rosa multiflora, but grazing needs to be followed by focused mechanical or chemical treatments to maintain control while allowing the regeneration of native tree species. [ABSTRACT FROM AUTHOR]

Nine ursane-type triterpenoids including three new ones 2α, 19α-dihydroxyurs-3-O-acetyltormentic acid (1), 1α, 2α, 3α, 20β-tetrahydroxyurs -13(18)-en-28-oic acid (2), and 2α, 3α, 20β, 24-tetrahydroxyurs-13(18)-en-28-oic acid (3) were isolated from the roots of Rosa multiflora. Their structures were elucidated by extensive spectroscopic methods, including NMR, MS, and IR spectroscopic analyses data. All the isolates were evaluated for their anti-inflammatory activity in vitro and the results showed that compounds 1–9 displayed moderate inhibitory activity with IC50 values ranging from 24.7 to 86.2 μM compared with the postitive control Amino guanidine (IC50 4.3 μM). [ABSTRACT FROM AUTHOR]

Obesity is one of the major risk factors for metabolic diseases worldwide. This study examined the effects of YC-1102, an extract derived from the roots of Rosa multiflora , on 3T3-L1 preadipocytes and high-fat diet (HFD)-induced obese mice. In vivo experiments involved the oral administration of YC-1102 (100, 150, and 200 mg/kg body weight) daily to mice for eight weeks. YC-1102 was found to downregulate the expressions of PPARγ and C/EBPα during adipogenesis, inhibiting adipocyte differentiation and upregulating the expression of PGC-1α for energy metabolism to enhance mitochondrial biogenesis and fatty acid oxidation. It has been shown that daily administration of YC-1102 to mice receiving a HFD prevented an increase in body weight and the accumulation of body fat. YC-1102 administration also reduced TG, TC, and LDL cholesterol levels, as well as glucose and leptin levels, and increased adiponectin levels, thus effectively inhibiting the metabolism of lipids. YC-1102-treated mice showed significant reductions in the mRNA expression of PPARγ and C/EBPα . The levels of PGC-1α involved in energy metabolism increased significantly in the YC-1102-treated mice when compared to the HFD-treated mice. According to the findings of this study, YC-1102 has a dual mechanism that reduces transcription factors that promote the differentiation of adipocytes and increases transcription factors that promote energy consumption.

Eijitsu, the fruits of Rosa multiflora Thunberg, is a traditional Japanese natural medicine and used as purgatives. The active constituents were identified as flavonol glycosides, multiflorin A (MF), and multinoside A (MSA), but mechanism of the purgative action is still unknown. We hypothesized that the flavonol glycosides 1 and 2 may exhibit the purgative actions through modulating intestinal epithelial barrier function. Then, this study aimed to investigate their effects on intestinal epithelial barrier function and possible molecular mechanisms in human intestinal Caco-2 cells. MF and MSA decreased transepithelial electrical resistance and increased paracellular permeability of Caco-2 cell monolayers. Expression of claudins (CLDNs) involved in paracellular permeability of ions and low-molecular substances was significantly decreased by the treatment with MF or MSA. The compounds increased the ratio of N -cadherin/ E -cadherin, expression of transforming growth factor- β and Slug, and phosphorylation level of Smad3, suggesting epithelial-mesenchymal transition activation, and epithelial-mesenchymal transition inhibition by transforming growth factor- β receptor kinase inhibitors completely recovered the decreased CLDNs expression caused by MF and MSA. Moreover, the increased paracellular permeability and the decreased CLDNs expression by the treatment with MF or MSA for 24 hours recovered to the same extent as the untreated group with the compounds by continuous culture in the growth medium alone for 48 hours. These results suggest that Eijitsu may be effective in preventing or relieving constipation symptoms, unless used chronically. Unlabelled Image [ABSTRACT FROM AUTHOR]

Giving land managers the ability to predict invasion patterns can provide planning tools for acquisition and management of protected areas. We compared the effects of roads and streams, two substantial pathways for delivery of invasive plant propagules and sources of disturbance that may facilitate invasions, on the abundance of non-native invasive plants in 27 protected areas in the Appalachian Mountains of the eastern United States. As an extension of our road analysis, we also evaluated specific road type as a predictor of protected area invadedness. We found that road and stream predictors did not improve on a model that included only other covariates (e.g., distance to an urban area, average canopy cover, average slope, edge-to-interior ratio, percent agricultural land, and percent developed land). In this model, only percent agricultural land was marginally significant in predicting parcel invadedness. However, we found that four-wheel drive (4WD) roads did predict protected area invadedness well relative to other road types (primary, secondary, and local) and better than a covariates-only model. The role of 4WD road density in predicting protected area invadedness may be explained by their relation to recreation, the unmaintained nature of 4WD roads, or the accumulation of mud and plant materials on 4WD vehicles. Although we found overall streams and roads in general to be poor predictors of invadedness of protected areas by invasive plants, we do propose that our finding of a relationship between plant invasions and density of 4WD roads merits further investigation in the future. [ABSTRACT FROM AUTHOR]

Rose rosette disease (RRD) is incited by a negative-sense RNA virus (genus Emaravirus), which is vectored by a wind-transported eriophyid mite (Phyllocoptes fructiphilus). Symptoms include witches broom/rosette-type growth, excessive prickles (thorns), discolored and distorted growth, and, unlike most other rose diseases, usually results in plant death. RRD is endemic to North America and was first described in Manitoba, Wyoming, and California in the 1940s. It has spread east with the aid of a naturalized rose species host and has become epidemic from the Great Plains to the East Coast of North America on garden roses in home and commercial landscapes where losses have been high. The disease was suggested to be incited by a virus from the beginning, but only recently has this been confirmed and the virus identified. The presence of the vector mite on roses has been associated with RRD since the first symptoms were described. However, more recently, the mite was demonstrated to be the vector of the disease and confirmed to transmit the virus itself. As a result of the RRD epidemic in North America and its effects on the national production and consumer markets for roses, a research team comprising five major universities (Texas, Florida, Tennessee, Oklahoma, and Delaware), a dozen growers and nurseries (all regions), six rose breeding programs (California, Wisconsin, Texas, and Pennsylvania), the major rose testing programs (Earth-Kind and AGRS), the major rose organization (American Rose Society), and the major trade organization AmericanHort has formed. This research project has been funded by the Specialty Crops Research Initiative through the U.S. Department of Agriculture (USDA) with the short-term objective of improving and disseminating best management practices (BMPs) and the long-term goal of identifying additional sources of resistance and developing the genetic tools to quickly transfer resistance into the elite commercial rose germplasm. [ABSTRACT FROM AUTHOR]

The draft genome sequence of a wild rose (Rosa multiflora Thunb.) was determined using Illumina MiSeq and HiSeq platforms. The total length of the scaffolds was 739,637,845 bp, consisting of 83,189 scaffolds, which was close to the 711 Mbp length estimated by k-mer analysis. N50 length of the scaffolds was 90,830 bp, and extent of the longest was 1,133,259 bp. The average GC content of the scaffolds was 38.9%. After gene prediction, 67,380 candidates exhibiting sequence homology to known genes and domains were extracted, which included complete and partial gene structures. This large number of genes for a diploid plant may reflect heterogeneity of the genome originating from self-incompatibility in R. multiflora. According to CEGMA analysis, 91.9% and 98.0% of the core eukaryotic genes were completely and partially conserved in the scaffolds, respectively. Genes presumably involved in flower color, scent and flowering are assigned. The results of this study will serve as a valuable resource for fundamental and applied research in the rose, including breeding and phylogenetic study of cultivated roses. [ABSTRACT FROM AUTHOR]

Rosa multifloraThunb. var. inermis andRosa roxburghiif.normalisare two important diploid species for rose breeding. Interspecific crosses between diploid species and tetraploid rose cultivars result in triploids with generally decreased fertility. A most promising gene transfer strategy is the production of fertile tetraploid plants before mating with tetraploids. In our study, germinating seeds ofR. multifloraandR. roxburghiiwere treated with colchicine, and cotyledon-stage seedlings ofR. multiflorawere treated with colchicine or trifluralin in order to obtain tetraploid plants. Also, various concentrations of antimitotic agents and different treatment durations were tested. The results showed the antimitotic agents affected the plant morphological characteristics (i.e. plant height, stem diameter) ofR. multifloraandR. roxburghii. Twenty-three tetraploid plants were obtained from the germinating seed treatments (21 fromR. multifloraand two fromR. roxburghii), but no tetraploid plants were obtained from the seedling treatments. The highest rate of chromosome doubling (25.0%) was achieved when germinating seeds ofR. multiflorawere treated with 0.2% colchicine for 12 h. At the same time, marked morphological variation was observed and analyzed among tetraploid plants and their corresponding diploids ofR. multiflora. [ABSTRACT FROM AUTHOR]

Measuring and predicting invasive plant abundance is critical for understanding impacts on ecosystems and economies. Although spatial abundance datasets remain rare, occurrence datasets are increasingly available across broad regional scales. We asked whether the frequency of these point occurrences can be used as a proxy for abundance of invasive plants. We compiled both occurrence and abundance data for 13 regionally important invasive plants in the northeast United States from herbarium records and several contributed distribution datasets. We integrated all available abundance information based on infested area, stem count, percent cover, or qualitative descriptions into abundance rankings ranging from 0 (absent) to 4 (highly abundant). Within equal-area grid cells of 800 m, we counted numbers of occurrence points and used ordinal regression to test whether higher densities of occurrence points increased the odds of a higher abundance ranking. We compiled a total of 86,854 occurrence points in 34,596 grid cells, of which 26,114 points (30%) within 11,976 cells (35%) had some form of abundance information. Eleven of the 13 species had a slight but significantly positive odds ratio; that is, more occurrence points of a species increased the odds that the species was abundant within the grid cell. However, the predictive ability of the models was poor (κ < 0.2) for the majority of species. Additionally, most grid cells contained only one or two occurrence points, making it impossible to infer abundance in all but a few locations. These results suggest that currently available occurrence datasets do not effectively represent abundance, which could explain why many distribution models based on occurrence data are poor predictors of abundance. Increased efforts to consistently collect and report invasive species abundance, ideally estimating both infested area and average cover, are strongly needed for regional-scale assessments of potential abundance and associated impact. [ABSTRACT FROM AUTHOR]

The aim of the study was to evaluate the efficacy of the multiflora rose var. “Jatar” (Rosa multifloraThunb. ex Murray) and the Virginia fanpetals (Sida hermaphroditaRusby) to phytoextract heavy metals from municipal sewage sludge. The 6-year field experiment involved four levels of fertilization with sewage sludge at doses of 0, 10, 20, 40, and 60 Mg DM (Dry Mass) sludge ha−1. The increasing doses of sewage sludge were found to significantly increase the yield of multiflora rose and Virginia fanpetals biomass. They also significantly increased the content of heavy metals in these plants. The highest uptake of heavy metals by the multiflora rose and Virginia fanpetals crops was recorded at the fertilization dose of 60 Mg DM ⋅ ha−1. Our investigations show that the Virginia fanpetals was more efficient in the phytoextraction of Cr, Ni, Cu, Zn, and Cd from the sewage sludge than the multiflora rose, due to the greater yields and higher heavy metal uptake by the former plant. In turn, the multiflora rose phytoextracted greater amounts of Pb from the sewage sludge. The analyses indicate that the Virginia fanpetals can be used for phytoremediation (phytoextraction) of heavy metals contained in sewage sludge. [ABSTRACT FROM AUTHOR]

Abstract Nonnative, invasive shrubs can affect human disease risk through direct and indirect effects on vector populations. Multiflora rose (Rosa multiflora) is a common invader within eastern deciduous forests where tick‐borne disease (e.g., Lyme disease) rates are high. We tested whether R. multiflora invasion affects blacklegged tick (Ixodes scapularis) abundance and at what scale. We sampled host‐seeking ticks at two spatial scales: fine scale, within R. multiflora‐invaded forest fragments; and patch scale, among R. multiflora‐invaded and R. multiflora‐free forest fragments. At a fine scale, we trapped 2.3 times more ticks under R. multiflora compared with paired traps 25 m away from R. multiflora. At the patch scale, we trapped 3.2 times as many ticks in R. multiflora‐free forests compared with R. multiflora‐invaded forests. Thus, ticks are concentrated beneath R. multiflora within invaded forests, but uninvaded forests support significantly more ticks. Among all covariates tested, leaf litter volume was the best predictor of tick abundance; at the patch scale, R. multiflora‐invaded forests had less leaf litter than uninvaded forests. We suggest that leaf litter availability at the patch scale plays a greater role in constraining tick abundance than the fine‐scale, positive effect of invasive shrubs.

The genus Rosa (roses) has long been used in traditional or folk medicine worldwide for the treatment of various types of arthritis including rheumatoid arthritis and osteoarthritis. The active constituents of Rosa spp., such as flavonoids, triterpenoids, and phytosterols, could act on different targets in the NF-κB signalling pathway, inhibit pro-inflammatory enzymes (e.g. MMPs and COX-2), lower the production of inflammatory cytokines and chemokines (e.g. TNF-α, IL-1β, IL-6, CCL5), and reduce oxidative stress, which in turn suppress inflammatory processes. Preclinical and clinical studies have demonstrated that these species possess analgesic, anti-arthritic, anti-inflammatory, anti-oxidative and bone-preserving activities. This review presents comprehensive overview of the mode and mechanism of action of various extracts, preparations, and active constituents from this genus. The dynamic beneficial effects of the products prepared from this genus in arthritis management are summarized. The Rosa genus is a treasure waiting for further exploration by researchers interested in the development of safe and effective anti-arthritic agents. [ABSTRACT FROM AUTHOR]

PREMISE OF THE STUDY: Functional trait plasticity in resource capture traits has been suggested as an underlying mechanism promoting invasive species establishment and spread. Earlier studies on this mechanism treat invasiveness as a discrete characteristic (i.e., invasive vs. noninvasive) and do not consider the potential impacts of evolutionary history. In the present study, we used a continuous measure of invasiveness and a phylogenetic framework to quantify the relationship between functional trait expression, plasticity, and invasiveness in Rosa. METHODS: In a manipulative greenhouse experiment, we evaluated how light availability affects functional traits and their plasticity in Rosa sp. and the out-group species, Potentilla recta, which vary in their invasiveness. KEY RESULTS: Across functional traits, we found no significant relationship between plasticity and invasiveness. However, more invasive roses demonstrated an ability to produce a more branched plant architecture, promoting optimal light capture. Invasiveness also was linked with lower photosynthetic and stomatal conductance rates, leading to increased water-use efficiency (WUE) in more invasive roses. CONCLUSIONS: Our results suggest that functional trait values, rather than plasticity, promote invasive rose success, counter to earlier predictions about the role of plasticity in invasiveness. Furthermore, our study indicates that invasive roses demonstrate key functional traits, such as increased WUE, to promote their success in the high-light, edge habitats they commonly invade. [ABSTRACT FROM AUTHOR]

Activation of peroxisome proliferator-activated receptors (PPAR) α/γ is known to inhibit the increases in matrix metalloproteinase (MMP) and reactive oxygen species (ROS) induced by ultraviolet light (UV). Extracts of natural herbs, such as Kochia scoparia and Rosa multiflora, have a PPAR α/γ dual agonistic effect. Therefore, we investigated whether and how they have an antiaging effect on photoaging skin. Eighteen-week-old hairless mice were irradiated with UVA 14 J/cm2 and UVB 40 mJ/cm2 three times a week for 8 weeks. A mixture of extracts of Kochia scoparia and Rosa multiflora (KR) was topically applied on the dorsal skin of photoaging mice twice a day for 8 weeks. Tesaglitazar, a known PPAR α/γ agonist, and vehicle (propylene glycol:ethanol = 7:3, v/v) were applied as positive and negative controls, respectively. Dermal effects (including dermal thickness, collagen density, dermal expression of procollagen 1 and collagenase 13) and epidermal effects (including skin barrier function, epidermal proliferation, epidermal differentiation, and epidermal cytokines) were measured and compared. In photoaging murine skin, KR resulted in a significant recovery of dermal thickness as well as dermal fibroblasts, although it did not change dermal collagen density. KR increased the expression of dermal transforming growth factor (TGF)-β. The dermal effects of KR were explained by an increase in procollagen 1 expression, induced by TGF-β, and a decrease in MMP-13 expression. KR did not affect basal transepidermal water loss (TEWL) or stratum corneum (SC) integrity, but did decrease SC hydration. It also did not affect epidermal proliferation or epidermal differentiation. KR decreased the expression of epidermal interleukin (IL)-1α. Collectively, KR showed possible utility as a therapeutic agent for photoaging skin, with few epidermal side effects such as epidermal hyperplasia or poor differentiation. [ABSTRACT FROM AUTHOR]

The relationship between initial population densities ( Pi) of Meloidogyne hapla on growth of three rose rootstocks ( Rosa corymbifera 'Laxa', R. multiflora and R. canina 'Inermis') and nematode population development was studied. Each plant species was inoculated with ranges of nematode densities of 0, 0.062, 0.125, 0.25, 0.50, 1, 2, 4, 8, 16, 32, 64 and 128 second-stage juvenile/g soil and were allowed to grow for 9 weeks. Seinhorst yield model [ABSTRACT FROM AUTHOR]

Rose is one of most popular ornamental plants in the world. The plant is of high economical value and great cultural importance. Low temperature exerts strong influence on the cultivation and commercial value of rose. The negative impacts could be genetically reduced through elucidating the mechanisms underlying plant cold tolerance. The Illumina Hiseq™ 2000 RNA-seq is a promising approach in gene expression analysis at the transcriptome level. With the transcriptome and DEG analysis, we investigated the gene expression profiles in response to cold stress of Rosa multiflora. The results shed light on the underlying molecular mechanisms of plant cold resistance. In the study, clean data that were generated from three samples of Rosa multiflora under different cold stress (i.e., CK, CT1 and CT2). A total of 61,864 unigenes with an average length of 1216 bp were obtained by assembling the data. A total of 42,553 complete and 1246 partial coding sequences (CDSs) were determined by protein database alignments and ESTScan prediction, respectively. Subsequently, we obtained functional annotations by aligning all unigenes with public protein databases (i.e., NR, Swiss-Prot, KEGG and COG). DEG analysis was performed to assess the changes in gene expression in cold condition (4 and 25 °C) using the FPKM method. The results indicated that there were 4966 up-regulated genes and 4592 down-regulated genes between CK and CT1, and 7915 up-regulated genes and 10,912 down-regulated genes between CK and CT2. We then performed GO enrichment and metabolic pathway enrichment analyses. A series of candidate genes that are involved in cold responsive pathways and a number of transcription factors were selected and discussed. We selected 15 up-regulated and five down-regulated unigenes in Rosa multiflora were quantified using qRT-PCR. The study provides a comprehensive overview of transcriptome response and gene expression profiling of Rosa multiflora in response to cold stress. The large number of transcriptomic sequences obtained in the study provides sufficient resources for molecular markers and gene cloning. The study facilities the understanding of the underlying mechanisms of cold resistance in Rosa multiflora. [ABSTRACT FROM AUTHOR]

Rose rosette disease is a disorder associated with infection by Rose rosette virus (RRV), a pathogen of roses that causes devastating effects on most garden cultivated varieties, and the wild invasive rose especially Rosa multiflora . Reliable and sensitive detection of this disease in early phases is needed to implement proper control measures. This study assesses a single primer-set based detection method for RRV and demonstrates its application in three different chemistries: Endpoint RT-PCR, TaqMan-quantitative RT-PCR (RT-qPCR) and SYBR Green RT-qPCR with High Resolution Melting analyses. A primer set (RRV2F/2R) was designed from consensus sequences of the nucleocapsid protein gene p3 located in the RNA 3 region of RRV. The specificity of primer set RRV2F/2R was validated in silico against published GenBank sequences and in-vitro against infected plant samples and an exclusivity panel of near-neighbor and other viruses that commonly infect Rosa spp. The developed assay is sensitive with a detection limit of 1 fg from infected plant tissue. Thirty rose samples from 8 different states of the United States were tested using the developed methods. The developed methods are sensitive and reliable, and can be used by diagnostic laboratories for routine testing and disease management decisions. [ABSTRACT FROM AUTHOR]

Municipalities are turning to ecological restoration of urban forests as a measure to improve air quality, ameliorate urban heat island effects, improve storm water infiltration, and provide other social and ecological benefits. However, community dynamics following urban forest restoration treatments are poorly documented. This study examines the long-term effects of ecological restoration undertaken in New York City, New York, USA, to restore native forest in urban park natural areas invaded by woody non-native plants that are regional problems. In 2009 and 2010, we sampled vegetation in 30 invaded sites in three large public parks that were restored 1988-1993, and 30 sites in three large parks that were similarly invaded but had not been restored. Data from these matched plots reveal that the restoration treatment achieved its central goals. After 15-20 years, invasive species removal followed by native tree planting resulted in persistent structural and compositional shifts, significantly lower invasive species abundance, a more complex forest structure, and greater native tree recruitment. Together, these findings indicate that successional trajectories of vegetation dynamics have diverged between restored forests and invaded forests that were not restored. In addition, the data suggest that future composition of these urban forest patches will be novel assemblages. Restored and untreated sites shared a suite of shade-intolerant, quickly-growing tree species that colonize disturbed sites, indicating that restoration treatments created sites hospitable for germination and growth of species adapted to high light conditions and disturbed soils. These findings yield an urban perspective on the use of succession theory in ecological restoration. Models of ecological restoration developed in more pristine environments must be modified for use in cities. By anticipating both urban disturbances and ecological succession, management of urban forest patches can be adjusted to better predict and direct long-term outcomes. An urban approach to ecological restoration must use realistic, flexible targets to preserve and enhance urban biodiversity for both short-term benefits and long-term sustainability. [ABSTRACT FROM AUTHOR]

Nonnative, invasive shrubs can affect human disease risk through direct and indirect effects on vector populations. Multiflora rose (Rosa multiflora) is a common invader within eastern deciduous forests where tick‐borne disease (e.g., Lyme disease) rates are high. We tested whether R. multiflora invasion affects blacklegged tick (Ixodes scapularis) abundance and at what scale. We sampled host‐seeking ticks at two spatial scales: fine scale, within R. multiflora‐invaded forest fragments; and patch scale, among R. multiflora‐invaded and R. multiflora‐free forest fragments. At a fine scale, we trapped 2.3 times more ticks under R. multiflora compared with paired traps 25 m away from R. multiflora. At the patch scale, we trapped 3.2 times as many ticks in R. multiflora‐free forests compared with R. multiflora‐invaded forests. Thus, ticks are concentrated beneath R. multiflora within invaded forests, but uninvaded forests support significantly more ticks. Among all covariates tested, leaf litter volume was the best predictor of tick abundance; at the patch scale, R. multiflora‐invaded forests had less leaf litter than uninvaded forests. We suggest that leaf litter availability at the patch scale plays a greater role in constraining tick abundance than the fine‐scale, positive effect of invasive shrubs. [ABSTRACT FROM AUTHOR]