Search

Summary Cuscuta campestris, a stem parasitic plant, has served as a valuable model plant for the exploration of plant–plant interactions and molecular trafficking. However, a major barrier to C. campestris research is that a method to generate stable transgenic plants has not yet been developed. Here, we describe the development of a Cuscuta transformation protocol using various reporter genes (GFP, GUS, or RUBY) and morphogenic genes (CcWUS2 and CcGRF/GIF), leading to a robust protocol for Agrobacterium‐mediated C. campestris transformation. The stably transformed and regenerated RUBY C. campestris plants produced haustoria, the signature organ of parasitic plants, and these were functional in forming host attachments. The locations of T‐DNA integration in the parasite genome were confirmed through TAIL‐PCR. Transformed C. campestris also produced flowers and viable transgenic seeds exhibiting betalain pigment, providing proof of germline transmission of the RUBY transgene. Furthermore, RUBY is not only a useful selectable marker for the Agrobacterium‐mediated transformation, but may also provide insight into the movement of molecules from C. campestris to the host during parasitism. Thus, the protocol for transformation of C. campestris reported here overcomes a major obstacle to Cuscuta research and opens new possibilities for studying parasitic plants and their interactions with hosts. [ABSTRACT FROM AUTHOR]

The main objective of this research was to conduct a comparative pollen morphological analysis of some representatives of the genus Cuscuta in relation to taxonomy. Investigations of 38 species and 1 variation revealed that not only the number, but the colpi length, as well as the exine ornamentation (at the SEM level), can be regarded as a diagnostic feature. For all the taxa studied, the common zonocolpate type of pollen was observed, represented by three variations: I) colpi long; II) colpi of medium length; III) colpi short. In combination with colpi length, variations in the number of colpi were also identified, such as: I) 3(4)-zonocolpate pollen grains with long colpi (in most of the species studied from subgenera Grammica and Cuscuta , as well as in C. monogyna from the subgenus Monogynella ); II) 4(3)-zonocolpate pollen grains, with long colpi ( C. cristata from subgenus Grammica ); III) 3-zonocolpate pollen grains both with long colpi and colpi of medium length ( C. abyssinic a from subgenus Cuscuta and C. africana , C. angulata from subgenus Pachystigma ); IV) 3-zonocolpate pollen grains with colpi of medium length were noted for species from all four subgenera ( C. cassytoides , C. lupuliformis from subgenus Monogynella , C. kotschyana from subgenus Cuscuta , C. nitida from subgenus Pachystigma and C. jalapensis , C. rostrata , C. suaveolens from subgenus Grammica ); V) 3–4- or 4-zonocolpate, with short colpi ( C. lehmanniana and C. gigantea from subgenus Monogynella respectively); VI) 5–6-zonocolpate, with short colpi ( C. reflexa from subgenus Monogynella ). Using SEM, three main types of exine ornamentation were also identified: perforate, foveolate and reticulate. The last type in the vast majority of the cases was presented in combination with echinae (rarely with spines or granules). The data revealed that the presence of the significant similarity of palyno-morphological characteristics in representatives of the subgenera Cuscuta , Pachystigma and Grammica , with the exception of the species Lepidanche adpressa (syn. C. compacta ), makes it difficult to create an identification key at the level of individual subgenera. Pollen features can be most clearly used only to distinguish the subgenus Monoginella , reflecting its certain isolation within the entire Cuscuta genus. The presence of a highly specialized reticulate exine ornamentation in Lepidanche adpressa (syn. C. compacta ), not identified for the pollen of any of the studied taxa of the subgenus Grammica , indicates a significant proximity of this species to the subgenus Monogynella . For the species C. reflexa , the obtained palyno-morphological data are consistent with the previous opinion about the separation of this species, as well as its more advanced position within the genus Cuscuta .

Parasitic lifestyle can often relax the constraint on the plastome, leading to gene pseudogenization and loss, and resulting in diverse genomic structures and rampant genome degradation. Although several plastomes of parasitic Cuscuta have been reported, the evolution of parasitism in the family Convolvulaceae which is linked to structural variations and reduction of plastome has not been well investigated. In this study, we assembled and collected 40 plastid genomes belonging to 23 species representing four subgenera of Cuscuta and ten species of autotrophic Convolvulaceae. Our findings revealed nine types of structural variations and six types of inverted repeat (IR) boundary variations in the plastome of Convolvulaceae spp. These structural variations were associated with the shift of parasitic lifestyle, and IR boundary shift, as well as the abundance of long repeats. Overall, the degradation of Cuscuta plastome proceeded gradually, with one clade exhibiting an accelerated degradation rate. We observed five stages of gene loss in Cuscuta, including NAD(P)H complex → PEP complex → Photosynthesis-related → Ribosomal protein subunits → ATP synthase complex. Based on our results, we speculated that the shift of parasitic lifestyle in early divergent time promoted relaxed selection on plastomes, leading to the accumulation of microvariations, which ultimately resulted in the plastome reduction. This study provides new evidence towards a better understanding of plastomic evolution, variation, and reduction in the genus Cuscuta.Key message: The gain of parasitism in Cuscuta does trigger structural variations of the plastome, and it may initiate the relaxed selection in plastid genes, which leads to accumulation of microvariations, subsequent plastome reduction and gene loss. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agriculture & Nature / Kahramanmaraş Sütçü İmam Üniversitesi Tarım & Doğa Dergisi is the property of Kahramanmaras Sutcu Imam Universitesi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract Background Many parasitic plants of the genera Striga and Cuscuta inflict huge agricultural damage worldwide. To form and maintain a connection with a host plant, parasitic plants deploy virulence factors (VFs) that interact with host biology. They possess a secretome that represents the complement of proteins secreted from cells and like other plant parasites such as fungi, bacteria or nematodes, some secreted proteins represent VFs crucial to successful host colonisation. Understanding the genome-wide complement of putative secreted proteins from parasitic plants, and their expression during host invasion, will advance understanding of virulence mechanisms used by parasitic plants to suppress/evade host immune responses and to establish and maintain a parasite-host interaction. Results We conducted a comparative analysis of the secretomes of root (Striga spp.) and shoot (Cuscuta spp.) parasitic plants, to enable prediction of candidate VFs. Using orthogroup clustering and protein domain analyses we identified gene families/functional annotations common to both Striga and Cuscuta species that were not present in their closest non-parasitic relatives (e.g. strictosidine synthase like enzymes), or specific to either the Striga or Cuscuta secretomes. For example, Striga secretomes were strongly associated with ‘PAR1’ protein domains. These were rare in the Cuscuta secretomes but an abundance of ‘GMC oxidoreductase’ domains were found, that were not present in the Striga secretomes. We then conducted transcriptional profiling of genes encoding putatively secreted proteins for the most agriculturally damaging root parasitic weed of cereals, S. hermonthica. A significant portion of the Striga-specific secretome set was differentially expressed during parasitism, which we probed further to identify genes following a ‘wave-like’ expression pattern peaking in the early penetration stage of infection. We identified 39 genes encoding putative VFs with functions such as cell wall modification, immune suppression, protease, kinase, or peroxidase activities, that are excellent candidates for future functional studies. Conclusions Our study represents a comprehensive secretome analysis among parasitic plants and revealed both similarities and differences in candidate VFs between Striga and Cuscuta species. This knowledge is crucial for the development of new management strategies and delaying the evolution of virulence in parasitic weeds.

Background: Many parasitic plants of the genera Striga and Cuscuta inflict huge agricultural damage worldwide. To form and maintain a connection with a host plant, parasitic plants deploy virulence factors (VFs) that interact with host biology. They possess a secretome that represents the complement of proteins secreted from cells and like other plant parasites such as fungi, bacteria or nematodes, some secreted proteins represent VFs crucial to successful host colonisation. Understanding the genome-wide complement of putative secreted proteins from parasitic plants, and their expression during host invasion, will advance understanding of virulence mechanisms used by parasitic plants to suppress/evade host immune responses and to establish and maintain a parasite-host interaction. Results: We conducted a comparative analysis of the secretomes of root (Striga spp.) and shoot (Cuscuta spp.) parasitic plants, to enable prediction of candidate VFs. Using orthogroup clustering and protein domain analyses we identified gene families/functional annotations common to both Striga and Cuscuta species that were not present in their closest non-parasitic relatives (e.g. strictosidine synthase like enzymes), or specific to either the Striga or Cuscuta secretomes. For example, Striga secretomes were strongly associated with 'PAR1' protein domains. These were rare in the Cuscuta secretomes but an abundance of 'GMC oxidoreductase' domains were found, that were not present in the Striga secretomes. We then conducted transcriptional profiling of genes encoding putatively secreted proteins for the most agriculturally damaging root parasitic weed of cereals, S. hermonthica. A significant portion of the Striga-specific secretome set was differentially expressed during parasitism, which we probed further to identify genes following a 'wave-like' expression pattern peaking in the early penetration stage of infection. We identified 39 genes encoding putative VFs with functions such as cell wall modification, immune suppression, protease, kinase, or peroxidase activities, that are excellent candidates for future functional studies. Conclusions: Our study represents a comprehensive secretome analysis among parasitic plants and revealed both similarities and differences in candidate VFs between Striga and Cuscuta species. This knowledge is crucial for the development of new management strategies and delaying the evolution of virulence in parasitic weeds. [ABSTRACT FROM AUTHOR]

Parasitic plants and their hosts communicate through haustorial connections. Nutrient deficiency is a common stress for plants, yet little is known about whether and how host plants and parasites communicate during adaptation to such nutrient stresses. In this study, we used transcriptomics and proteomics to analyze how soybean (Glycine max) and its parasitizing dodder (Cuscuta australis) respond to nitrate and phosphate deficiency (-N and -P). After -N and -P treatment, the soybean and dodder plants exhibited substantial changes of transcriptome and proteome, although soybean plants showed very few transcriptional responses to -P and dodder did not show any transcriptional changes to either -N or -P. Importantly, large-scale interplant transport of mRNAs and proteins was detected. Although the mobile mRNAs only comprised at most 0.2% of the transcriptomes, the foreign mobile proteins could reach 6.8% of the total proteins, suggesting that proteins may be the major forms of interplant communications. Furthermore, the interplant mobility of macromolecules was specifically affected by the nutrient regimes and the transport of these macromolecules was very likely independently regulated. This study provides new insight into the communication between host plants and parasites under stress conditions.

Introduction: Cuscuta, (Ces as Persian name) is a parasitic plant with different biological effects and applications. The metabolic profile and effects of the Ces depend on the host on which it grows. Its main components are phenols and flavonoids. Considering the antioxidant effects of these compounds, the purpose of this research was to investigate the antioxidant activities and total phenolic and flavonoid contents of Cuscuta as well as Mellissa officinalis and Alhaji murarum as hosts. Methods: Aqueous, hydroalcoholic extracts of the Cuscuta grown on two hosts were prepared separately. Hydroalcoholic extracts of host plants were also prepared. Total phenolic and flavonoid contents were evaluated using Folin- Ciocalteu reagent and aluminum chloride colorimetric assays, respectively. In order to investigate the antioxidant activity, the ability of extracts to scavenge DPPH free radical (DPPH 2, 2-(diphenyl-1-picrylhydrazyl) and their capacity to reduce iron 3+ion were measured by FRAP method. Results: The results showed that all the examined extracts have significant phenolic and flavonoid contents. The highest antioxidant activity was observed in hydroalcoholic extracts, which was proportional to the amount of phenolic and flavonoid contents in the extracts. In addition, the extracts of host plants were richer than the parasite extracts. The extract of Mellissa officinalis showed better effects than Alhaji murarum in all of four investigated factors. Conclusion: According to the findings of the present study, the hydroalcoholic extracts of the Cuscuta plants are rich in phenolic and flavonoid compounds, which may be the cause of the antioxidant activity. Of course, the compounds and effects of Cuscuta depend on the host. In future studies, the plant can be grown in different hosts.

Cuscuta species (dodders) are agriculturally destructive, parasitic angiosperms. These parasitic plants use haustoria as physiological bridges to extract nutrients and water from hosts. Cuscuta campestris has a broad host range and wide geographical distribution. While some wild tomato relatives are resistant, cultivated tomatoes are generally susceptible to C. campestris infestations. However, some specific Heinz tomato (Solanum lycopersicum) hybrid cultivars exhibit resistance to dodders in the field, but their defense mechanism was previously unknown. Here, we discovered that the stem cortex in these resistant lines responds with local lignification upon C. campestris attachment, preventing parasite entry into the host. Lignin Induction Factor 1 (LIF1, an AP2-like transcription factor), SlMYB55, and Cuscuta R-gene for Lignin-based Resistance 1, a CC-NBS-LRR (CuRLR1) are identified as factors that confer host resistance by regulating lignification. SlWRKY16 is upregulated upon C. campestris infestation and potentially negatively regulates LIF1 function. Intriguingly, CuRLR1 may play a role in signaling or function as an intracellular receptor for receiving Cuscuta signals or effectors, thereby regulating lignification-based resistance. In summary, these four regulators control the lignin-based resistance response in specific Heinz tomato cultivars, preventing C. campestris from parasitizing resistant tomatoes. This discovery provides a foundation for investigating multilayer resistance against Cuscuta species and has potential for application in other essential crops attacked by parasitic plants.

Parasitic plants invade their host through their invasive organ, the haustorium. This organ connects to the vasculature of the host roots and hijacks water and nutrients. Although parasitism has evolved independently in plants, haustoria formation follows a similar mechanism throughout different plant species, highlighting the developmental plasticity of plant tissues. Here, we compare three types of haustoria formed by the root and shoot in the plant parasites Striga and Cuscuta. We discuss mechanisms underlying the interactions with their hosts and how different approaches have contributed to major understanding of haustoria formation and host invasion. We also illustrate the role of auxin and cytokinin in controlling this process. [ABSTRACT FROM AUTHOR]

Parasitic plants reduce crop yield worldwide. Dodder (Cuscuta campestris) is a stem parasite that attaches to its host, using haustoria to extract nutrients and water. We analyzed the transcriptome of six C. campestris tissues and identified a key gene, LATERAL ORGAN BOUNDARIES DOMAIN 25 (CcLBD25), as highly expressed in prehaustoria and haustoria. Gene coexpression networks from different tissue types and laser-capture microdissection RNA-sequencing data indicated that CcLBD25 could be essential for regulating cell wall loosening and organogenesis. We employed host-induced gene silencing by generating transgenic tomato (Solanum lycopersicum) hosts that express hairpin RNAs to target and down-regulate CcLBD25 in the parasite. Our results showed that C. campestris growing on CcLBD25 RNAi transgenic tomatoes transited to the flowering stage earlier and had reduced biomass compared with C. campestris growing on wild-type (WT) hosts, suggesting that parasites growing on transgenic plants were stressed due to insufficient nutrient acquisition. We developed an in vitro haustorium system to assay the number of prehaustoria produced on strands from C. campestris. Cuscuta campestris grown on CcLBD25 RNAi tomatoes produced fewer prehaustoria than those grown on WT tomatoes, indicating that down-regulating CcLBD25 may affect haustorium initiation. Cuscuta campestris haustoria growing on CcLBD25 RNAi tomatoes exhibited reduced pectin digestion and lacked searching hyphae, which interfered with haustorium penetration and formation of vascular connections. The results of this study elucidate the role of CcLBD25 in haustorium development and might contribute to developing parasite-resistant crops.

Background The molecular evolution of organellar genomes in angiosperms has been studied extensively, with some lineages, such as parasitic ones, displaying unique characteristics. Parasitism has emerged 12 times independently in angiosperm evolution. Holoparasitism is the most severe form of parasitism, and is found in ~10 % of parasitic angiosperms. Although a few holoparasitic species have been examined at the molecular level, most reports involve plastomes instead of mitogenomes. Parasitic plants establish vascular connections with their hosts through haustoria to obtain water and nutrients, which facilitates the exchange of genetic information, making them more susceptible to horizontal gene transfer (HGT). HGT is more prevalent in the mitochondria than in the chloroplast or nuclear compartments. Scope This review summarizes current knowledge on the plastid and mitochondrial genomes of holoparasitic angiosperms, compares the genomic features across the different lineages, and discusses their convergent evolutionary trajectories and distinctive features. We focused on Balanophoraceae (Santalales), which exhibits extraordinary traits in both their organelles. Conclusions Apart from morphological similarities, plastid genomes of holoparasitic plants also display other convergent features, such as rampant gene loss, biased nucleotide composition and accelerated evolutionary rates. In addition, the plastomes of Balanophoraceae have extremely low GC and gene content, and two unexpected changes in the genetic code. Limited data on the mitochondrial genomes of holoparasitic plants preclude thorough comparisons. Nonetheless, no obvious genomic features distinguish them from the mitochondria of free-living angiosperms, except for a higher incidence of HGT. HGT appears to be predominant in holoparasitic angiosperms with a long-lasting endophytic stage. Among the Balanophoraceae, mitochondrial genomes exhibit disparate evolutionary paths with notable levels of heteroplasmy in Rhopalocnemis and unprecedented levels of HGT in Lophophytum. Despite their differences, these Balanophoraceae share a multichromosomal mitogenome, a feature also found in a few free-living angiosperms. [ABSTRACT FROM AUTHOR]

Dodders (Cuscuta chinensis) are rootless and holoparasitic herbs that can infect a variety of host plants, including the vitally important economic and bioenergy crop soybean (Glycine max). Although dodder parasitism severely affects the physiology of host plants, little is known about its effects on fungal communities and root secondary metabolites in hosts. In this study, variations in root-associated fungal communities and root metabolites of soybean under different parasitism conditions were investigated using ITS rRNA gene sequencing and UPLC–MS/MS metabolome detection technologies. The results showed that dodder parasitism significantly altered the composition and diversity of the fungal communities in the rhizosphere and endosphere of soybean. The relative abundance of the potential pathogenic fungus Alternaria significantly increased in the root endosphere of dodder-parasitized soybean. Furthermore, correlation analysis indicated that the fungal community in the root endosphere was susceptible to soil factors under dodder parasitism. Meanwhile, the content of soil total nitrogen was significantly and positively correlated with the relative abundance of Alternaria in the rhizosphere and endosphere of soybean. Metabolomic analysis indicated that dodder parasitism altered the accumulation of flavonoids in soybean roots, with significant upregulation of the contents of kaempferol and its downstream derivatives under different parasitism conditions. Taken together, this study highlighted the important role of dodder parasitism in shaping the fungal communities and secondary metabolites associated with soybean roots, providing new insights into the mechanisms of multiple interactions among dodder, soybean, microbial communities and the soil environment. [ABSTRACT FROM AUTHOR]

The segregation of chromosomes depends on the centromere. Most species are monocentric, with the centromere restricted to a single region per chromosome. In some organisms, the monocentric organization changed to holocentric, in which the centromere activity is distributed over the entire chromosome length. However, the causes and consequences of this transition are poorly understood. Here, we show that the transition in the genus Cuscuta was associated with dramatic changes in the kinetochore, a protein complex that mediates the attachment of chromosomes to microtubules. We found that in holocentric Cuscuta species, the KNL2 genes were lost; the CENP-C, KNL1, and ZWINT1 genes were truncated; the centromeric localization of CENH3, CENP-C, KNL1, MIS12, and NDC80 proteins was disrupted; and the spindle assembly checkpoint (SAC) degenerated. Our results demonstrate that holocentric Cuscuta species lost the ability to form a standard kinetochore and do not employ SAC to control the attachment of microtubules to chromosomes. [ABSTRACT FROM AUTHOR]

The angiosperm genus Cuscuta lives as an almost achlorophyllous root- and leafless holoparasite and has therefore occupied scientists for more than a century. The 'evolution' of Cuscuta research started with early studies that established the phylogenetic framework for this unusual genus. It continued to produce groundbreaking cytological, morphological, and physiological insight throughout the second half of the 20th century and culminated in the last two decades in exciting discoveries regarding the molecular basis of Cuscuta parasitism that were facilitated by the modern 'omics' tools and traceable fluorescent marker technologies of the 21st century. This review will show how present activities are inspired by those past breakthroughs. It will describe significant milestones and recurring themes of Cuscuta research and connect these to the remaining as well as newly evolving questions and future directions in this research field that is expected to sustain its strong growth in the future. [ABSTRACT FROM AUTHOR]

Parasitic plants of the genus Cuscuta penetrate shoots of host plants with haustoria and build a connection to the host vasculature to exhaust water, solutes and carbohydrates. Such infections usually stay unrecognized by the host and lead to harmful host plant damage. Here, we show a molecular mechanism of how plants can sense parasitic Cuscuta. We isolated an 11 kDa protein of the parasite cell wall and identified it as a glycine-rich protein (GRP). This GRP, as well as its minimal peptide epitope Crip21, serve as a pathogen-associated molecular pattern and specifically bind and activate a membrane-bound immune receptor of tomato, the Cuscuta Receptor 1 (CuRe1), leading to defense responses in resistant hosts. These findings provide the initial steps to understand the resistance mechanisms against parasitic plants and further offer great potential for protecting crops by engineering resistance against parasitic plants.

Parasitic flowering plants represent a diverse group of angiosperms, ranging from exotic species with limited distribution to prominent weeds, causing significant yield losses in agricultural crops. The major damage caused by them is related to the extraction of water and nutrients from the host, thus decreasing vegetative growth, flowering, and seed production. Members of the root parasites of the Orobanchaceae family and stem parasites of the genus Cuscuta are among the most aggressive and damaging weeds, affecting both monocotyledonous and dicotyledonous crops worldwide. Their control and eradication are hampered by the extreme seed longevity and persistence in soil, as well as their taxonomic position, which makes it difficult to apply selective herbicides not damaging to the hosts. The selection of resistant cultivars is among the most promising approaches to deal with this matter, although still not widely employed due to limited knowledge of the molecular mechanisms of host resistance and inheritance. The current review aims to summarize the available information on host resistance with a focus on agriculturally important parasitic plants and to outline the future perspectives of resistant crop cultivar selection to battle the global threat of parasitic plants. [ABSTRACT FROM AUTHOR]

Main conclusion: Most species in Cuscuta subgenus Grammica retain many photosynthesis-related plastid genes, generally under purifying selection. A group of holoparasitic species in section Subulatae may have lost their plastid genomes entirely. The c. 153 species of plants belonging to Cuscuta subgenus Grammica are all obligate stem parasites. However, some have completely lost the ability to conduct photosynthesis while others retain photosynthetic machinery and genes. The plastid genome that primarily encodes key photosynthesis genes functions as a bellwether for how reliant plants are on primary production. This research assembles and analyses 17 plastomes across Cuscuta subgenus Grammica with the aim of characterizing the state of the plastome in each of its sections. By comparing the structure and content of plastid genomes across the subgenus, as well as by quantifying the selection acting upon each gene, we reconstructed the patterns of plastome change within the phylogenetic context for this group. We found that species in 13 of the 15 sections that comprise Grammica retain the bulk of plastid photosynthesis genes and are thus hemiparasitic. The complete loss of photosynthesis can be traced to two clades: the entire section Subulatae and a complex of three species within section Ceratophorae. We were unable to recover any significant plastome sequences from section Subulatae, suggesting that plastomes in these species are either drastically reduced or lost entirely. [ABSTRACT FROM AUTHOR]

Parasitic plants are notorious for causing serious agricultural losses in many countries. Specialized intrusive organs, haustoria, confer on parasitic plants the ability to acquire water and nutrients from their host plants. Investigating the mechanism involved in haustorium development not only reveals the fascinating mystery of how autotrophic plants evolved parasitism but also provides the foundation for developing more effective methods to control the agricultural damage caused by parasitic plants. Cuscuta species, also known as dodders, are one of the most well-known and widely spread stem holoparasitic plants. Although progress has been made recently in understanding the evolution and development of haustoria in root parasitic plants, more and more studies indicate that the behaviors between root and stem haustorium formation are distinct, and the mechanisms involved in the formation of these organs remain largely unknown. Unlike most endoparasites and root holoparasitic plants, which have high host-specificity and self-or kinrecognition to avoid forming haustoria on themselves or closely related species, auto-parasitism and hyper-parasitism are commonly observed among Cuscuta species. In this review, we summarize the current understanding of haustorium development in dodders and the unique characteristics of their parasitizing behaviors. We also outline the advantages of using Cuscuta species as model organisms for haustorium development in stem holoparasitic plants, the current unknown mysteries and limitations in the Cuscuta system, and potential future research directions to overcome these challenges. [ABSTRACT FROM AUTHOR]

Background and Objective: Many biological activities and pharmacological usages have been revealed for the Cuscuta species. The present study aimed to assess the beneficial effects of Cuscuta on removing skin dark spots in healthy individuals, which is an important cosmetic concern, especially in women. Materials and Methods: This prospective, interventional before–after trial was conducted in 70 healthy individuals without any evidence of skin or systemic disorders who presented for consultation on removing skin darkening. The Cuscuta extract was prepared and then assessed for plant quality control and lack of microbial contamination. The content of melanin at baseline and at 1 and 3 months after intervention was assessed using Dermacatch, an accurate skin colorimetric measurement tool. Results: Comparison of the melanin content of the lesions and treated area to the surrounding normal area at baseline and at 1 month after treatment showed a significant reduction in melanin content from 519.61 ± 45.09 to 498.50 ± 39.35 (P < 0.001). This reducing trend remained significant from the first month to the third month after treatment (from 498.50 ± 39.35 to 483.53 ± 40.99, P < 0.001). This decreasing trend was persistent even after adjusting baseline characteristics including gender, age, and duration of skin lesions. Both patients and investigators had high satisfaction level with the anti-melanogenesis effect of Cuscuta extract. Conclusion: Cuscuta extract is useful for removing hyperpigmented lesions and for skin lightening in healthy individuals. [ABSTRACT FROM AUTHOR]

Abstract Background The morning glories (Convolvulaceae) are distributed worldwide and produce economically important crops, medicinal herbs, and ornamentals. Members of this family are diverse in morphological characteristics and trophic modes, including the leafless parasitic Cuscuta (dodders). Organelle genomes were generally used for studying plant phylogeny and genomic variations. Notably, plastomes in parasitic plants always show non-canonical features, such as reduced size and accelerated rates. However, few organelle genomes of this group have been sequenced, hindering our understanding of their evolution, and dodder mitogenome in particular. Results We assembled 22 new mitogenomes and 12 new plastomes in Convolvulaceae. Alongside previously known ones, we totally analyzed organelle genomes of 23 species in the family. Our sampling includes 16 leafy autotrophic species and 7 leafless parasitic dodders, covering 8 of the 12 tribes. Both the plastid and mitochondrial genomes of these plants have encountered variations that were rarely observed in other angiosperms. All of the plastomes possessed atypical IR boundaries. Besides the gene and IR losses in dodders, some leafy species also showed gene and intron losses, duplications, structural variations, and insertions of foreign DNAs. The phylogeny reconstructed by plastid protein coding sequences confirmed the previous relationship of the tribes. However, the monophyly of ‘Merremieae’ and the sister group of Cuscuta remained uncertain. The mitogenome was significantly inflated in Cuscuta japonica, which has exceeded over 800 kb and integrated massive DNAs from other species. In other dodders, mitogenomes were maintained in small size, revealing divergent evolutionary strategies. Mutations unique to plants were detected in the mitochondrial gene ccmFc, which has broken into three fragments through gene fission and splicing shift. The unusual changes likely initially happened to the common ancestor of the family and were caused by a foreign insertion from rosids followed by double-strand breaks and imprecise DNA repairs. The coding regions of ccmFc expanded at both sides after the fission, which may have altered the protein structure. Conclusions Our family-scale analyses uncovered unusual scenarios for both organelle genomes in Convolvulaceae, especially in parasitic plants. The data provided valuable genetic resources for studying the evolution of Convolvulaceae and plant parasitism.

Background and Objective: Many biological activities and pharmacological usages have been revealed for the Cuscuta species. The present study aimed to assess the beneficial effects of Cuscuta on removing skin dark spots in healthy individuals, which is an important cosmetic concern, especially in women. Materials and Methods: This prospective, interventional before–after trial was conducted in 70 healthy individuals without any evidence of skin or systemic disorders who presented for consultation on removing skin darkening. The Cuscuta extract was prepared and then assessed for plant quality control and lack of microbial contamination. The content of melanin at baseline and at 1 and 3 months after intervention was assessed using Dermacatch, an accurate skin colorimetric measurement tool. Results: Comparison of the melanin content of the lesions and treated area to the surrounding normal area at baseline and at 1 month after treatment showed a significant reduction in melanin content from 519.61 ± 45.09 to 498.50 ± 39.35 (P < 0.001). This reducing trend remained significant from the first month to the third month after treatment (from 498.50 ± 39.35 to 483.53 ± 40.99, P < 0.001). This decreasing trend was persistent even after adjusting baseline characteristics including gender, age, and duration of skin lesions. Both patients and investigators had high satisfaction level with the anti-melanogenesis effect of Cuscuta extract. Conclusion: Cuscuta extract is useful for removing hyperpigmented lesions and for skin lightening in healthy individuals.

mRNAs are transported within a plant through phloem. Aphids are phloem feeders and dodders (Cuscuta spp.) are parasites which establish phloem connections with host plants. When aphids feed on dodders, whether there is trafficking of mRNAs among aphids, dodders, and host plants and if aphid feeding affects the mRNA transfer between dodders and hosts are unclear. We constructed a green peach aphid (GPA, Myzus persicae)-dodder (Cuscuta australis)-cucumber (Cucumis sativus) tritrophic system by infesting GPAs on C. australis, which parasitized cucumber hosts. We found that GPA feeding activated defense-related phytohormonal and transcriptomic responses in both C. australis and cucumbers and large numbers of mRNAs were found to be transferred between C. australis and cucumbers and between C. australis and GPAs; importantly, GPA feeding on C. australis greatly altered inter-species mobile mRNA profiles. Furthermore, three cucumber mRNAs and three GPA mRNAs could be respectively detected in GPAs and cucumbers. Moreover, our statistical analysis indicated that mRNAs with high abundances and long transcript lengths are likely to be mobile. This study reveals the existence of inter-species and even inter-kingdom mRNA movement among insects, parasitic plants, and parasite hosts, and suggests complex regulation of mRNA trafficking.

Objective: Cuscuta epithymum (CE) is one of the most popular medicinal plants in the world. However, detailed information about its toxicity is not available. Hence, this study aimed to evaluate the safety profile of CE ethanolic extract in vitro and in vivo.Materials and Methods: The extract's in vitro toxicity profile was investigated on normal fibroblast and cervical cancer cells by cytotoxicity test. In the next step, acute oral and intraperitoneal (i.p.) toxicity of the CE extract was evaluated in Wistar rats and BALB/c mice, respectively. Sub-acute oral toxicity was also examined by administering repeated oral doses of the CE extract (50, 200, and 500 mg/kg) to Wistar rats for 28 days.Results: The CE extract exhibited a significant cytotoxicity on both normal (IC50 0.82 mg/ml, p

Parasitic plant genus Cuscuta is important both economically and ecologically. This study is the result of more than fifteen years of herbarium and field studies in preparation for the floristic account of the genus in Nueva Flora de Chile. Eleven species that belong to three sections of subgenus Grammica were confirmed from Chile. Two historically reported species, C. epithymum and C. grandiflora, were not corroborated by the existing evidence. An identification key, typification, detailed descriptions and illustrations were provided to facilitate the identification of species, and their taxonomy was discussed, outlining remaining problems. Geographical distribution, ecology and host range of species were detailed. Results strongly suggested that several species are likely rare (e.g., C. andina, C. rustica, C. pauciflora) or even extinct (C. werdermannii), emphasizing the need for concerted efforts to locate these species in the wild and establish their conservation status.

Convolvulaceae is a cosmopolitan family with rich morphological characteristics and important economic values. However, the phylogenetic relationships among the major branches or tribes in the family have not been fully resolved. In order to resolve these relationships, we sampled the complete plastome sequences from 40 species, representing eight tribes of Convolvulaceae, and reconstructed phylogenetic trees by using both maximum likelihood and Bayesian inference approaches. The results were as follows:(1)Convolvulaceae plastomes had the typical quadripartite structure, with the plastome size ranging from 113 273 to 164 112 bp and including 66-79 protein-coding genes.(2)Phylogenomic analyses using five DNA matrixes(i.e., WCG, CDS, LSC, IR, and SSC)showed that the topologies of the WCG and CDS trees were basically the same, with slight differences in support values for some branches. Topological differences were found between LSC and WCG topologies, especially for the positions of Cuscuteae, Dichondreae and Cresseae. The AU and SH tests showed that topological conflicts were significant between the WCG matrix and the SSC and IR matrixes.(3)All phylogenetic analyses confirmed that Cuscuta and Dichondreae were nested in Convolvuloideae and should be treated as tribes.(4)Phylogenetic relationships among the eight tribes were well resolved using the WCG and CDS matrixes: Cardiochlamyeae and Erycibeae formed a clade as the first divergent group of Convolvuloideae, followed by Cuscuteae, with the remaining five tribes forming two major clades.(5)The phylogenomic analyses confirmed that Merremieae were polyphyletic, especially Merremia, and that the circumscription and taxonomy of both Merremieae and Merremia will need revision. [ABSTRACT FROM AUTHOR]

Numerous narrow xylem tracheary elements (tracheids and vessels) are present in liana stems, along with a few wide vessels that perform the main water-conducting function. This trait, known as “vessel dimorphism”, has been identified in studies on water-conducting tissue in autotrophic plants, including a large number of perennial climbing plants and a number of annual vines. Information is lacking on the presence of vessel dimorphism in parasitic plants of the lianescent habit. In this study, we performed a structural analysis of stems in the autotrophic herbaceous vines of Convolvulus arvensis L. and Calystegia sepium (L.) R. Br., as well as in the parasitic vines of Cuscuta monogyna Vahl, Cuscuta planiflora Ten., Cuscuta approximata Bab., and Cuscuta campestris Yunck., of the family of Convolvulaceae Horan. The xylem of C. arvensis and C. sepium contains a few wide conductive elements and many narrow ones. This feature is typical of autotrophic climbing plants. Only narrow tracheary elements are present in the xylem of the parasitic vines of the genus of Cuscuta L. (dodders). The total number of the tracheary elements is an order of magnitude less in the dodders than it is in the autotrophic vines. It is possible that the autotrophic ancestor of dodders lost the characteristic feature of the xylem of climbing plants, known as vessel dimorphism, during its transition to the parasitic lifestyle.

Dodders (Cuscuta chinensis) are rootless and holoparasitic herbs that can infect a variety of host plants, including the vitally important economic and bioenergy crop soybean (Glycine max). Although dodder parasitism severely affects the physiology of host plants, little is known about its effects on fungal communities and root secondary metabolites in hosts. In this study, variations in root-associated fungal communities and root metabolites of soybean under different parasitism conditions were investigated using ITS rRNA gene sequencing and UPLC–MS/MS metabolome detection technologies. The results showed that dodder parasitism significantly altered the composition and diversity of the fungal communities in the rhizosphere and endosphere of soybean. The relative abundance of the potential pathogenic fungus Alternaria significantly increased in the root endosphere of dodder-parasitized soybean. Furthermore, correlation analysis indicated that the fungal community in the root endosphere was susceptible to soil factors under dodder parasitism. Meanwhile, the content of soil total nitrogen was significantly and positively correlated with the relative abundance of Alternaria in the rhizosphere and endosphere of soybean. Metabolomic analysis indicated that dodder parasitism altered the accumulation of flavonoids in soybean roots, with significant upregulation of the contents of kaempferol and its downstream derivatives under different parasitism conditions. Taken together, this study highlighted the important role of dodder parasitism in shaping the fungal communities and secondary metabolites associated with soybean roots, providing new insights into the mechanisms of multiple interactions among dodder, soybean, microbial communities and the soil environment.

Weevils of the genus Smicronyx Schönherr, 1843 are a relatively widespread taxonomic group in the Western Palaearctic. Despite its widespread distribution, faunistic data on it are scarce, and there are even entire regions with no current faunistic data. Here, we report on the first records of the genus from Latvia. Two species have been recorded in Latvia for the first time: Smicronyx jungermanniae Reich, 1797 and Smicronyx coecus Reich, 1797. Faunistic data on this taxonomic group in the Baltic region are scarce. The aim of this article is to raise knowledge of this taxon in the hope that it will lead to new discoveries elsewhere. [ABSTRACT FROM AUTHOR]

This study considers nutrient content of hydrophytic host populations (Impatiens capensis and Justicia americana) and their obligate holoparasite, Cuscuta gronovii. Comparisons of mineral content in aboveground organs between non-parasitized (control) and parasitized plants were also evaluated. While Cuscuta appeared to have limited impact on plant size for J. americana, the parasite did foster decreases in biomass for I. capensis. When differences in mineral content were observed between hosts and controls, parasitized plants maintained higher nutrient levels. No differences in macronutrient content were observed in parasitized J. americana relative to uninfected controls. In contrast, there were elevated N, P, and S in I. capensis hosts compared to uninfected plants. Although it is possible that Cuscuta parasitism enhanced nutrient uptake in I. capensis, the appearance of higher macronutrients could reflect selective foraging by Cuscuta. That is, given the option between multiple hosts, Cuscuta may have the ability to select hosts with higher nutritional status. There were also higher Mn concentrations in both host species when parasitized, and higher Fe, Cu, and Al in parasitized I. capensis. Aluminum was particularly high (>1000 ppm) in I. capensis hosts, possibly reflecting the role of Al in eliciting antioxidant and/or pathogenic defenses in parasitized plants. [ABSTRACT FROM AUTHOR]

Convolvulaceae is a family of c. 2,000 species, distributed across 60 currently recognized genera. It includes species of high economic importance, such as the crop sweet potato (Ipomoea batatas L.), the ornamental morning glories (Ipomoea L.), bindweeds (Convolvulus L.), and dodders, the parasitic vines (Cuscuta L.). Earlier phylogenetic studies, based predominantly on chloroplast markers or a single nuclear region, have provided a framework for systematic studies of the family, but uncertainty remains at the level of the relationships among subfamilies, tribes, and genera, hindering evolutionary inferences and taxonomic advances. One of the enduring enigmas has been the relationship of Cuscuta to the rest of Convolvulaceae. Other examples of unresolved issues include the monophyly and relationships within Merremieae, the “bifid-style” clade (Dicranostyloideae), as well as the relative positions of Erycibe Roxb. and Cardiochlamyeae. In this study, we explore a large dataset of nuclear genes generated using Angiosperms353 kit, as a contribution to resolving some of these remaining phylogenetic uncertainties within Convolvulaceae. For the first time, a strongly supported backbone of the family is provided. Cuscuta is confirmed to belong within family Convolvulaceae. “Merremieae,” in their former tribal circumscription, are recovered as non-monophyletic, with the unexpected placement of Distimake Raf. as sister to the clade that contains Ipomoeeae and Decalobanthus Ooststr., and Convolvuleae nested within the remaining “Merremieae.” The monophyly of Dicranostyloideae, including Jacquemontia Choisy, is strongly supported, albeit novel relationships between genera are hypothesized, challenging the current tribal delimitation. The exact placements of Erycibe and Cuscuta remain uncertain, requiring further investigation. Our study explores the benefits and limitations of increasing sequence data in resolving higher-level relationships within Convolvulaceae, and highlights the need for expanded taxonomic sampling, to facilitate a much-needed revised classification of the family.

Parasitic flowering plants represent a diverse group of angiosperms, ranging from exotic species with limited distribution to prominent weeds, causing significant yield losses in agricultural crops. The major damage caused by them is related to the extraction of water and nutrients from the host, thus decreasing vegetative growth, flowering, and seed production. Members of the root parasites of the Orobanchaceae family and stem parasites of the genus Cuscuta are among the most aggressive and damaging weeds, affecting both monocotyledonous and dicotyledonous crops worldwide. Their control and eradication are hampered by the extreme seed longevity and persistence in soil, as well as their taxonomic position, which makes it difficult to apply selective herbicides not damaging to the hosts. The selection of resistant cultivars is among the most promising approaches to deal with this matter, although still not widely employed due to limited knowledge of the molecular mechanisms of host resistance and inheritance. The current review aims to summarize the available information on host resistance with a focus on agriculturally important parasitic plants and to outline the future perspectives of resistant crop cultivar selection to battle the global threat of parasitic plants.

Background: The morning glories (Convolvulaceae) are distributed worldwide and produce economically important crops, medicinal herbs, and ornamentals. Members of this family are diverse in morphological characteristics and trophic modes, including the leafless parasitic Cuscuta (dodders). Organelle genomes were generally used for studying plant phylogeny and genomic variations. Notably, plastomes in parasitic plants always show non-canonical features, such as reduced size and accelerated rates. However, few organelle genomes of this group have been sequenced, hindering our understanding of their evolution, and dodder mitogenome in particular. Results: We assembled 22 new mitogenomes and 12 new plastomes in Convolvulaceae. Alongside previously known ones, we totally analyzed organelle genomes of 23 species in the family. Our sampling includes 16 leafy autotrophic species and 7 leafless parasitic dodders, covering 8 of the 12 tribes. Both the plastid and mitochondrial genomes of these plants have encountered variations that were rarely observed in other angiosperms. All of the plastomes possessed atypical IR boundaries. Besides the gene and IR losses in dodders, some leafy species also showed gene and intron losses, duplications, structural variations, and insertions of foreign DNAs. The phylogeny reconstructed by plastid protein coding sequences confirmed the previous relationship of the tribes. However, the monophyly of 'Merremieae' and the sister group of Cuscuta remained uncertain. The mitogenome was significantly inflated in Cuscuta japonica, which has exceeded over 800 kb and integrated massive DNAs from other species. In other dodders, mitogenomes were maintained in small size, revealing divergent evolutionary strategies. Mutations unique to plants were detected in the mitochondrial gene ccmFc, which has broken into three fragments through gene fission and splicing shift. The unusual changes likely initially happened to the common ancestor of the family and were caused by a foreign insertion from rosids followed by double-strand breaks and imprecise DNA repairs. The coding regions of ccmFc expanded at both sides after the fission, which may have altered the protein structure. Conclusions: Our family-scale analyses uncovered unusual scenarios for both organelle genomes in Convolvulaceae, especially in parasitic plants. The data provided valuable genetic resources for studying the evolution of Convolvulaceae and plant parasitism. [ABSTRACT FROM AUTHOR]

Osteoporosis is one of the most common diseases in the world which resulted in heavy socioeconomic burden and a public health threat. Glucocorticoid-induced osteoporosis (GIO) is the most common secondary reason of osteoporosis. Therapeutic strategies using traditional Chinese medicine are under investigation for osteoporosis, with efforts to improve efficacy and clarify the mechanism. The combination of Eucommia, Cuscuta, and Drynaria is widely used in traditional Chinese decoction for osteoporosis treatment, but the experimental efficacy and mechanism are still unclear. Administration of E.C.D. extracts (Eucommia, Cuscuta, and Drynaria) in experimental GIO rats resulted in decreased urinal calcium, phosphorus loss, and decreased expression of RANKL, CTX in serum, increased serum calcium, phosphorus, and OPG level. E.C.D. extracts also improved bone density, structural integrity, and biomechanical function in experimental GIO rats. These finding were associated with E.C.D. extracts' treatment efficacy to GIO in vivo. The balance between osteoclast and osteoblast activity is essential for bone remodeling and bone related disease. The E.C.D. extracts inhibited Raw 264.7 cell differentiation to osteoclast in vitro. On the other hand, it promoted OPG expression of bone marrow mesenchymal stromal cells (MSCs) which can suppress the osteoclast genesis. E.C.D. extracts also increased the Wnt1 and Runx2 expression which are related to osteoblast formation. It also regulated the paracrine effect of MSC to inhibit osteoclast differentiation. The analysis of HPLC and comprehensive pharmacology identified the constituents of E.C.D. extracts and the potential osteoporosis-related targets mediated by E.C.D. extracts. The KEGG enrichment analysis suggested that PI3K/Akt pathway may be involved in the regulation osteoclast genesis by E.C.D. extracts and the result of Western blot of vitro assays proved it. Collectively, these data demonstrate E.C.D. extracts can inhibit osteoclast differentiation to foster experimental osteoporosis both in vivo and in vitro and it may exert the function of inhibiting osteoclast differentiation through PI3K/Akt pathway. [ABSTRACT FROM AUTHOR]

Osteoporosis is one of the most common diseases in the world which resulted in heavy socioeconomic burden and a public health threat. Glucocorticoid-induced osteoporosis (GIO) is the most common secondary reason of osteoporosis. Therapeutic strategies using traditional Chinese medicine are under investigation for osteoporosis, with efforts to improve efficacy and clarify the mechanism. The combination of Eucommia, Cuscuta, and Drynaria is widely used in traditional Chinese decoction for osteoporosis treatment, but the experimental efficacy and mechanism are still unclear. Administration of E.C.D. extracts (Eucommia, Cuscuta, and Drynaria) in experimental GIO rats resulted in decreased urinal calcium, phosphorus loss, and decreased expression of RANKL, CTX in serum, increased serum calcium, phosphorus, and OPG level. E.C.D. extracts also improved bone density, structural integrity, and biomechanical function in experimental GIO rats. These finding were associated with E.C.D. extracts’ treatment efficacy to GIO in vivo. The balance between osteoclast and osteoblast activity is essential for bone remodeling and bone related disease. The E.C.D. extracts inhibited Raw 264.7 cell differentiation to osteoclast in vitro. On the other hand, it promoted OPG expression of bone marrow mesenchymal stromal cells (MSCs) which can suppress the osteoclast genesis. E.C.D. extracts also increased the Wnt1 and Runx2 expression which are related to osteoblast formation. It also regulated the paracrine effect of MSC to inhibit osteoclast differentiation. The analysis of HPLC and comprehensive pharmacology identified the constituents of E.C.D. extracts and the potential osteoporosis-related targets mediated by E.C.D. extracts. The KEGG enrichment analysis suggested that PI3K/Akt pathway may be involved in the regulation osteoclast genesis by E.C.D. extracts and the result of Western blot of vitro assays proved it. Collectively, these data demonstrate E.C.D. extracts can inhibit osteoclast differentiation to foster experimental osteoporosis both in vivo and in vitro and it may exert the function of inhibiting osteoclast differentiation through PI3K/Akt pathway.

The polyommatine lycaenid butterfly Pseudolucia jujuyensis Bálint, Eisele et Johnson, 2000 (Lepidoptera) was described on the basis of a single male from Coraya, Humahuaca, Jujuy, Argentina; its bionomics has remained unknown. Based on subsequently collected materials the species is now recorded from Yavi in Argentina and Torotoro in Bolivia (the latter representing a new country record). Eggs are recorded from Cuscuta sp. (Convolvulaceae), a suspected host plant of the larva. The bionomics and behaviour of the species are discussed. The species is considered to be endemic to the cold arid steppe (Prepuna) vegetation of low diversity, found along the eastern side of the Andes below the Altiplano in Bolivia and Argentina. [ABSTRACT FROM AUTHOR]

Objective: Cuscuta epithymum (CE) is one of the most popular medicinal plants in the world. However, detailed information about its toxicity is not available. Hence, this study aimed to evaluate the safety profile of CE ethanolic extract in vitro and in vivo. Materials and Methods: The extract's in vitro toxicity profile was investigated on normal fibroblast and cervical cancer cells by cytotoxicity test. In the next step, acute oral and intraperitoneal (i.p.) toxicity of the CE extract was evaluated in Wistar rats and BALB/c mice, respectively. Sub-acute oral toxicity was also examined by administering repeated oral doses of the CE extract (50, 200, and 500 mg/kg) to Wistar rats for 28 days. Results: The CE extract exhibited a significant cytotoxicity on both normal (IC50 0.82 mg/ml, p<0.001) and cancer cells (IC50 1.42 mg/ml, p<0.001). Acute oral administration of a single dose of CE extract (175-5000 mg/kg) did not cause mortality; however, its i.p. administration caused mortality at doses greater than 75 mg/kg (i.p. LD50 154.8 mg/kg). In the sub-acute toxicity test, no significant effects in terms of weight change, organ weights, blood chemistry, or kidney pathology were observed. However, at 200 and 500 mg/kg doses, the CE extract significantly increased liver pathological scores compared to the control group (p<0.05 and p<0.01, respectively). Conclusion: CE exhibited toxicities in i.p. acute and repeated oral dose administrations. It showed identical cytotoxicity against normal and cancer cells. This herb must be prescribed cautiously by traditional medicine practitioners. [ABSTRACT FROM AUTHOR]

Abstract Background Dodder (Cuscuta spp., Convolvulaceae) species are obligate leaf- and rootless parasites that totally depend on hosts to survive. Dodders naturally graft themselves to host stems to form vascular fusion, from which they obtain nutrients and water. In addition, dodders and their hosts also exchange various other molecules, including proteins, mRNAs, and small RNAs. It is very likely that vascular fusion also allows inter-plant translocation of systemic signals between dodders and host plants and these systemic signals may have profound impacts on the physiology of dodder and host plants. Herbivory is a common biotic stress for plants. When a dodder parasite is attacked by lepidopteran insects, how dodder responds to caterpillar feeding and whether there are inter-plant communications between the host plants and the parasites is still poorly understood. Results Here, wild-type (WT) tobacco and a tobacco line in which jasmonic acid (JA) biosynthesis was silenced (AOC-RNAi) were used as the hosts, and the responses of dodders and their host plants to herbivory by Spodoptera litura caterpillars on the dodders were investigated. It was found that after caterpillar attack, dodders grown on AOC-RNAi tobacco showed much a smaller number of differentially expressed genes, although the genotypes of the tobacco plants did not have an effect on the simulated S. litura feeding-induced JA accumulation in dodders. We further show that S. litura herbivory on dodder also led to large changes in transcriptome and defensive metabolites in the host tobacco, leading to enhanced resistance to S. litura, and the JA pathway of tobacco host is critical for these systemic responses. Conclusions Our findings indicate that during caterpillar attack on dodder, the JA pathway of host plant is required for the proper transcriptomic responses of both dodder and host plants. This study highlights the importance of the host JA pathway in regulating the inter-plant systemic signaling between dodder and hosts.

Cuscuta, commonly known as dodder, is a genus of family convolvolaceace. Approximately 170 species of Cuscuta are extensively distributed in temperate and subtropical areas of the world. Species of this genus are widely used as essential constituents in functional foods and traditional medicinal systems. Various parts of many members of Cuscuta have been found efficacious against a variety of diseases. Phytochemical investigations have confirmed presence of biologically active moieties such as flavonoids, alkaloids, lignans, saponines, phenolics, tannins, and fatty acids. Pharmacological studies and traditional uses of these plants have proved that they are effective antibacterial, antioxidant, antiostioporotic, hepatoprotective, anti-inflammatory, antitumor, antipyretic, antihypertensive, analgesic, anti hair fall, and antisteriogenic agents.

To explore the potential mechanism in Cuscuta sinensis on diarrhea-type irritable bowel syndrome using network pharmacology and molecular docking techniques. First, the active components and related targets of Cuscuta were found setting oral utilization >30% and drug-like properties greater than or equal to 0.18 as filter information from TCMSP database. The targets of diarrheal irritable bowel syndrome were compiled by searching DrugBank, GeneCards, OMIM, PharmGkb, and TTD databases. The intersections of drugs and targets related to the disease were taken for gene ontology enrichment and Kyoto encyclopedia of genes and genomes enrichment analyses, to elucidate the potential molecular mechanisms and pathway information of Cuscuta sinensis for the treatment of diarrheal irritable bowel syndrome. The protein-protein interaction network was constructed by using the STRING database and visualized with Cytoscape&#95;v3.10.0 software to find the protein-protein interaction network core At last, molecular docking was performed to validate the combination of active compounds with the core target. The target information of Cuscuta and diarrhea-type irritable bowel syndrome was compiled, which can be resulted in 11 active compounds such as quercetin, kaempferol, isorhamnetin, β-sitosterol, and another 17 core targets such as TP53, IL6, AKT1, IL1B, TNF, EGFR, etc, whose Kyoto encyclopedia of genes and genomes was enriched in the pathways of lipids and atherosclerosis, chemical carcinogenesis-receptor activation, PI3K-Akt signaling pathway, and fluid shear stress and atherosclerosis, etc. Docking demonstrated that the core targets and the active compounds were able to be better combined. Cuscuta chinensis may exert preventive effects on diarrhea-type irritable bowel syndrome by reducing intestinal inflammation, protecting intestinal mucosa, and playing an important role in antioxidant response through multi-targets and multi-pathways., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2024 the Author(s). Published by Wolters Kluwer Health, Inc.)

Cuscuta campestris is one of the most widespread and most harmful parasitic plants in the world. It regularly infests economically important crops substantially reducing their yield. Its host preference has been frequently investigated in natural habitats, but studies have usually been performed at only one site. In this study, I tested the hypothesis that host-preference studies performed at a single site provide information only about local individuals of the host species and not about the species of hosts in general. The preferential status of host species was investigated in different geographical regions, in different species environments. Altogether 1847 relationships between parasite and plant species were examined and categorized at 171 places in Hungary. The used method took into account the frequency and intensity of infestations on the hosts, the proportion of resource use and availability, the resource distribution as well as the defence mechanisms of the hosts. The frequency and intensity of infestations greatly varied amongst the 174 detected host species. The results confirmed that frequently parasitized hosts of C. campestris are not necessarily preferred. Most host species have infestations of varying intensity in different species environments. Poaceae species were found to differ from each other in the extent to which they support the parasite's growth. The study revealed also that C. campestris does not always develop haustoria on individuals of those species, which are unable to contribute significantly to its growth. [ABSTRACT FROM AUTHOR]

Plant grafting is generally performed between closely related species. Recently, we have discovered that Nicotiana species of Solanaceae show the ability to graft with distantly related plant species beyond the family. Graft adhesion with diverse angiosperms by Nicotiana species was probably facilitated by the secretion of a subclade of ß-1,4-glucanases. The capability of interfamily grafting was also found in the model Orobanchaceae hemiparasitic plant, Phtheirospermum japonicum, which naturally invades to the tissues of host plants of different families. Transcriptome analysis indicated that the same clade of ß-1,4-glucanase plays an important role in plant parasitism. Thus, the tissue adhesion between distant plant species occurs both naturally and artificially. Here, we further observed the capability of interfamily grafting in the stem holoparasitic genus, Cuscuta. These findings indicate that the natural process of tissue adhesion is a potential clue to improve plant-grafting techniques.

Copyright of Canadian Field-Naturalist is the property of Ottawa Field Naturalists' Club and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The parasitic plant dodder has specific metabolites that sometimes have anti-cancer properties. Due to the nature of this plant, the profile of metabolites in this plant is greatly affected by the host plant, which can enhance its anti-cancer properties. In the present study, Cuscuta was grown on fennel and camelthorn hosts. The extracts from dodder were applied to breast and colorectal cancer cell lines, and their cytotoxic properties were evaluated. HPLC identified compounds of phenolic acids and flavonoids in cuscuta grown on camelthorn and fennel hosts. The ethanolic extracts from Cuscuta were applied to the colorectal cancer (HT-29) and breast cancer (MDA-MB-231) cell lines, and their cytotoxic properties were evaluated. The cytotoxic activity of the extracts was performed by 3-(4,5-Dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay. These extracts were tested under comparable conditions at different concentrations (100, 200, 300, and 400 μg/ml). All extracts showed dose-dependent cytotoxic activity on both cell lines. Both extracts significantly inhibit the proliferation of cancer cell lines. According to the results, camelthorn extract has more lethality than fennel, and the inhibitory capacity of fennel extract is relatively more minor in both cases. The IC50 value of dodder growm on camelthorn ethanolic extract on (HT-29) and (MDA-MB-231) in 72 hours was 27.73 and 39.80 μg/ml, respectively, whereas the IC50 value of dodder growm on fennel ethanolic extract on (HT-29) and (MDA-MB-231) in 72 hours was 53.51 and 206 μg/ml. The greater cytotoxicity of dodder extract on camelthorn is probably due to the higher anti-cancer properties than fennel. It seems that applying dodder extract grown on medicinal hosts is a natural and inexpensive approach to extracting and diversifying the medicinal properties of various medicinal plants, including fennel and camelthorn. [ABSTRACT FROM AUTHOR]

Parasitic plants live in intimate physical connection with other plants serving as their hosts. These host plants provide the inorganic and organic compounds that the parasites need for their propagation. The uptake of the macromolecular compounds happens through symplasmic connections in the form of plasmodesmata. In contrast to regular plasmodesmata, which connect genetically identical cells of an individual plant, the plasmodesmata that connect the cells of host and parasite join separate individuals belonging to different species and are therefore termed “interspecific”. The existence of such interspecific plasmodesmata was deduced either indirectly using molecular approaches or observed directly by ultrastructural analyses. Most of this evidence concerns shoot parasitic Cuscuta species and root parasitic Orobanchaceae, which can both infect a large range of phylogenetically distant hosts. The existence of an interspecific chimeric symplast is both striking and unique and, with exceptions being observed in closely related grafted plants, exist only in these parasitic relationships. Considering the recent technical advances and upcoming tools for analyzing parasitic plants, interspecific plasmodesmata in parasite/host connections are a promising system for studying secondary plasmodesmata. For open questions like how their formation is induced, how their positioning is controlled and if they are initiated by one or both bordering cells simultaneously, the parasite/host interface with two adjacent distinguishable genetic systems provides valuable advantages. We summarize here what is known about interspecific plasmodesmata between parasitic plants and their hosts and discuss the potential of the intriguing parasite/host system for deepening our insight into plasmodesmatal structure, function, and development.

In our study, we investigated some physiological and ecological aspects of the life of Cuscuta racemosa Mart. (Convolvulaceae) plants with the hypothesis that they recognise different hosts at a distance from them, and they change their survival strategy depending on what they detect. We also hypothesised that, as an attempt of prolonging their survival through photosynthesis, the synthesis of chlorophylls (a phenomenon not completely explained in these parasitic plants) would be increased if the plants don’t detect a host. We quantified the pigments related to photosynthesis in different treatments and employed techniques such as electrophysiological time series recording, analyses of the complexity of the obtained signals, and machine learning classification to test our hypotheses. The results demonstrate that the absence of a host increases the amounts of chlorophyll a, chlorophyll b, and β-carotene in these plants, and the content varied depending on the host presented. Besides, the electrical signalling of dodders changes according to the species of host perceived in patterns detectable by machine learning techniques, suggesting that they recognise from a distance different host species. Our results indicate that electrical signalling might underpin important processes such as foraging in plants. Finally, we found evidence for a likely process of attention in the dodders toward the host plants. This is probably to be the first empirical evidence for attention in plants and has important implications on plant cognition studies.

Sunlight filtered by green plant tissue becomes diminished in its ratio of red to far‐red wavelengths (R:FR). Some parasitic plants exploit this change by growing towards regions of low R:FR to locate host plants. In principle, variation in R:FR can also convey ecologically relevant information about host proximity or architecture. Here, we demonstrate that the parasitic vine Cuscuta epilinum Weihe (Convolvulaceae) can distinguish fine‐scale differences in R:FR associated with differences in the proximity and shape of potential host plants. We conducted dual‐choice experiments by placing parasite seedlings between targets, including low R:FR fields manipulated via LED lighting and pairs of model plants exhibiting realistic R and FR reflectance but differing in proximity or shape. Seedlings consistently distinguished between low‐R:FR fields of differing intensity. Furthermore, they exhibited preferences for nearer plant models versus identical models placed 4 cm further away and between same‐sized models exhibiting shape differences. Our results indicate that parasites can discriminate minute differences in R:FR signatures corresponding to host factors (proximity and shape) that impact seedling survival. This keen sensory ability underpins the parasite's sophisticated foraging behaviour and highlights the broader importance of light cues in plant ecology. Parasitic dodder vines in the genus Cuscuta can detect variation in the ratio of red to far‐red light (R:FR) and actively grow towards regions of low R:FR, which can indicate the presence of potential host plants. In this study, we show that dodder seedlings can also discriminate fine‐scale differences in R:FR fields associated with ecologically relevant differences in the proximity of potential hosts as well as differences in host plant architecture. [ABSTRACT FROM AUTHOR]

Parasitic plants live in intimate physical connection with other plants serving as their hosts. These host plants provide the inorganic and organic compounds that the parasites need for their propagation. The uptake of the macromolecular compounds happens through symplasmic connections in the form of plasmodesmata. In contrast to regular plasmodesmata, which connect genetically identical cells of an individual plant, the plasmodesmata that connect the cells of host and parasite join separate individuals belonging to different species and are therefore termed "interspecific". The existence of such interspecific plasmodesmata was deduced either indirectly using molecular approaches or observed directly by ultrastructural analyses. Most of this evidence concerns shoot parasitic Cuscuta species and root parasitic Orobanchaceae, which can both infect a large range of phylogenetically distant hosts. The existence of an interspecific chimeric symplast is both striking and unique and, with exceptions being observed in closely related grafted plants, exist only in these parasitic relationships. Considering the recent technical advances and upcoming tools for analyzing parasitic plants, interspecific plasmodesmata in parasite/host connections are a promising system for studying secondary plasmodesmata. For open questions like how their formation is induced, how their positioning is controlled and if they are initiated by one or both bordering cells simultaneously, the parasite/host interface with two adjacent distinguishable genetic systems provides valuable advantages. We summarize here what is known about interspecific plasmodesmata between parasitic plants and their hosts and discuss the potential of the intriguing parasite/host system for deepening our insight into plasmodesmatal structure, function, and development. [ABSTRACT FROM AUTHOR]