Pelargonium
Bromoviridae
Chenopodium quinoa
Plant Somatic Embryogenesis Techniques
Anacardic Acids
Carmovirus
Complete nucleotide sequence of Pelargonium zonate spot virus and its relationship with the family Bromoviridae. (1/26)
The complete sequence of the Pelargonium zonate spot virus (PZSV) genome was determined. It comprises 8477 nt, distributed in three positive-strand RNA species encoding four proteins. RNA-1 is 3383 nt long, with an ORF that encodes a polypeptide with a molecular mass of 108 419 Da (denoted protein 1a). This protein contains the conserved sequence motifs I-III of type I methyltransferases and the seven consensus motifs of the helicases of superfamily 1. RNA-2 is 2435 nt long and encodes a major polypeptide with a molecular mass of 78 944 Da (denoted protein 2a), which shows identity to the RNA-dependent RNA polymerases of positive-strand RNA viruses. RNA-3 is 2659 nt long and contains two major ORFs. The first ORF is located in the 5' portion of the genome and sequence comparison of the putative translation product revealed similarities with the 30K superfamily of virus movement proteins. The second ORF is located in the 3' half and encodes the viral coat protein, which is expressed via a subgenomic RNA, RNA-4. The transcription initiation site of RNA-4 maps to the intergenic region of RNA-3. The organization of the PZSV genome, including the primary structure of terminal non-coding regions, strongly suggests that this virus belongs to the family Bromoviridae. The overall biological and genomic characteristics of PZSV indicate affinities in diverging directions with one or other of the virus species in this family, thus enabling it to be considered as a possible representative of a new genus within the family Bromoviridae. (+info)Nitrogen- and storage-affected carbohydrate partitioning in high-light-adapted Pelargonium cuttings in relation to survival and adventitious root formation under low light. (2/26)
BACKGROUND AND AIMS: The aim of this study was to determine the role of nitrogen- and storage-affected carbohydrate availability in rooting of pelargonium cuttings, focusing on the environmental conditions of stock plant cultivation at low latitudes, transport of cuttings, and rooting under the low light that prevails during the winter rooting period in Central European greenhouses. METHODS: Carbohydrate partitioning in high-light-adapted cuttings of the cultivar 'Isabell' was studied in relation to survival and adventitious root formation under low light. Effects of a graduated supply of mineral nitrogen to stock plants and of cutting storage were examined. KEY RESULTS: Nitrogen deficiency raised starch levels in excised cuttings, whereas the concentrations of glucose and total sugars in leaves and the basal stem were positively correlated with internal total nitrogen (Nt). Storage reduced starch to trace levels in all leaves, but sugar levels were only reduced in tissues of non-nitrogen deficient cuttings. Sugars accumulated in the leaf lamina of stored cuttings during the rooting period, whereas carbohydrates were simultaneously exhausted in all other cutting parts including the petioles, thereby promoting leaf senescence. The positive correlation between initial Nt and root number disappeared after storage. Irrespectively of storage, higher pre-rooting leaf glucose promoted subsequent sugar accumulation in the basal stem and final root number. The positive relationships between initial sugar levels in the stems with cutting survival and in leaves with root formation under low light were confirmed in a sample survey with 21 cultivars provided from different sources at low latitudes. CONCLUSIONS: The results indicate that adventitious rooting of pelargonium cuttings can be limited by the initial amount of nitrogen reserves. However, this relationship reveals only small plasticity and is superimposed by a predominant effect of carbohydrate availability that depends on the initial leaf sugar levels, when high-light adaptation and low current light conditions impair net carbon assimilation. (+info)Multiple major increases and decreases in mitochondrial substitution rates in the plant family Geraniaceae. (3/26)
BACKGROUND: Rates of synonymous nucleotide substitutions are, in general, exceptionally low in plant mitochondrial genomes, several times lower than in chloroplast genomes, 10-20 times lower than in plant nuclear genomes, and 50-100 times lower than in many animal mitochondrial genomes. Several cases of moderate variation in mitochondrial substitution rates have been reported in plants, but these mostly involve correlated changes in chloroplast and/or nuclear substitution rates and are therefore thought to reflect whole-organism forces rather than ones impinging directly on the mitochondrial mutation rate. Only a single case of extensive, mitochondrial-specific rate changes has been described, in the angiosperm genus Plantago. RESULTS: We explored a second potential case of highly accelerated mitochondrial sequence evolution in plants. This case was first suggested by relatively poor hybridization of mitochondrial gene probes to DNA of Pelargonium hortorum (the common geranium). We found that all eight mitochondrial genes sequenced from P. hortorum are exceptionally divergent, whereas chloroplast and nuclear divergence is unexceptional in P. hortorum. Two mitochondrial genes were sequenced from a broad range of taxa of variable relatedness to P. hortorum, and absolute rates of mitochondrial synonymous substitutions were calculated on each branch of a phylogenetic tree of these taxa. We infer one major, approximately 10-fold increase in the mitochondrial synonymous substitution rate at the base of the Pelargonium family Geraniaceae, and a subsequent approximately 10-fold rate increase early in the evolution of Pelargonium. We also infer several moderate to major rate decreases following these initial rate increases, such that the mitochondrial substitution rate has returned to normally low levels in many members of the Geraniaceae. Finally, we find unusually little RNA editing of Geraniaceae mitochondrial genes, suggesting high levels of retroprocessing in their history. CONCLUSION: The existence of major, mitochondrial-specific changes in rates of synonymous substitutions in the Geraniaceae implies major and reversible underlying changes in the mitochondrial mutation rate in this family. Together with the recent report of a similar pattern of rate heterogeneity in Plantago, these findings indicate that the mitochondrial mutation rate is a more plastic character in plants than previously realized. Many molecular factors could be responsible for these dramatic changes in the mitochondrial mutation rate, including nuclear gene mutations affecting the fidelity and efficacy of mitochondrial DNA replication and/or repair and--consistent with the lack of RNA editing--exceptionally high levels of "mutagenic" retroprocessing. That the mitochondrial mutation rate has returned to normally low levels in many Geraniaceae raises the possibility that, akin to the ephemerality of mutator strains in bacteria, selection favors a low mutation rate in plant mitochondria. (+info)Transfer of phloem-mobile substances from the host plants to the holoparasite Cuscuta sp. (4/26)
During the development of the haustorium, searching hyphae of the parasite and the host parenchyma cells are connected by plasmodesmata. Using transgenic tobacco plants expressing a GFP-labelled movement protein of the tobacco mosaic virus, it was demonstrated that the interspecific plasmodesmata are open. The transfer of substances in the phloem from host to the parasite is not selective. After simultaneous application of (3)H-sucrose and (14)C-labelled phloem-mobile amino acids, phytohormones, and xenobiotica to the host, corresponding percentages of the translocated compounds are found in the parasite. An open continuity between the host phloem and the Cuscuta phloem via the haustorium was demonstrated in CLSM pictures after application of the phloem-mobile fluorescent probes, carboxyfluorescein (CF) and hydroxypyrene trisulphonic acid (HPTS), to the host. Using a Cuscuta bridge (14)C-sucrose and the virus PVY(N) were transferred from one host plant to the another. The results of translocation experiments with labelled compounds, phloem-mobile dyes and the virus should be considered as unequivocal evidence for a symplastic transfer of phloem solutes between Cuscuta species and their compatible hosts. (+info)Coat protein sequence shows that Cucumber mosaic virus isolate from geraniums (Pelargonium spp.) belongs to subgroup II. (5/26)
A viral disease was identified on geraniums (Pelargonium spp.) grown in a greenhouse at the Institute of Himalayan Bioresource Technology (IHBT), Palampur, exhibiting mild mottling and stunting. The causal virus (Cucumber mosaic virus, CMV) was identified and characterized on the basis of host range, aphid transmission, enzyme linked immunosorbent assay (ELISA), DNA-RNA hybridization and reverse transcription polymerase chain reaction (RT-PCR). A complete coat protein (CP) gene was amplified using degenerate primers and sequenced. The CP gene showed nucleotide and amino acid homology up to 97%-98% and 96%-99%, respectively with the sequences of CMV subgroup II. The CP gene also showed homologies of 75%-97% in nucleotide and 77%-96% in amino acid with the CMV Indian isolates infecting various crops. On the basis of sequence homology, it was concluded that CMV-infecting geraniums in India belong to subgroup II. (+info)The complete chloroplast genome sequence of Pelargonium x hortorum: organization and evolution of the largest and most highly rearranged chloroplast genome of land plants. (6/26)
The chloroplast genome of Pelargonium x hortorum has been completely sequenced. It maps as a circular molecule of 217,942 bp and is both the largest and most rearranged land plant chloroplast genome yet sequenced. It features 2 copies of a greatly expanded inverted repeat (IR) of 75,741 bp each and, consequently, diminished single-copy regions of 59,710 and 6,750 bp. Despite the increase in size and complexity of the genome, the gene content is similar to that of other angiosperms, with the exceptions of a large number of pseudogenes, the recognition of 2 open reading frames (ORF56 and ORF42) in the trnA intron with similarities to previously identified mitochondrial products (ACRS and pvs-trnA), the losses of accD and trnT-ggu and, in particular, the presence of a highly divergent set of rpoA-like ORFs rather than a single, easily recognized gene for rpoA. The 3-fold expansion of the IR (relative to most angiosperms) accounts for most of the size increase of the genome, but an additional 10% of the size increase is related to the large number of repeats found. The Pelargonium genome contains 35 times as many 31 bp or larger repeats than the unrearranged genome of Spinacia. Most of these repeats occur near the rearrangement hotspots, and 2 different associations of repeats are localized in these regions. These associations are characterized by full or partial duplications of several genes, most of which appear to be nonfunctional copies or pseudogenes. These duplications may also be linked to the disruption of at least 1 but possibly 2 or 3 operons. We propose simple models that account for the major rearrangements with a minimum of 8 IR boundary changes and 12 inversions in addition to several insertions of duplicated sequence. (+info)Integrated approach for detection of nonculturable cells of Ralstonia solanacearum in asymptomatic Pelargonium spp. cuttings. (7/26)
(+info)Mite-control activities of active constituents isolated from Pelargonium graveolens against house dust mites. (8/26)
The mite-control activities of materials obtained from Pelargonium graveolens oil against Dermatophagoides farinae and D. pteronyssinus were examined using an impregnated fabric disk bioassay and were compared with those shown by commercial benzyl benzoate and N,N-diethylm- toluamide (DEET). Purification of the biologically active constituents from P. graveolens oil was done by silica gel chromatography and high performance liquid chromatography. The structures of the active components were analyzed by EI/MS, (1)H-NMR, (13)C-NMR, (1)H-(13)C COSYNMR, and DEPT-NMR spectra, and were identified as geraniol (C(10)H(18)O, MW 154.25, trans-3,7-dimethyl-2,6- octadien-1-ol) and beta-citronellol (C(10)H(20)O, MW 156.27, 3,7-dimethyl-6-octen-1-ol). Based on the LD50 values, the most toxic compound was geraniol (0.26 microg/cm(2)), followed by beta-citronellol (0.28 microg/cm(2)), benzyl benzoate (10.03 microg/ cm(2)), and DEET (37.12 microg/cm(2)) against D. farinae. In the case of D. pteronyssinus, geraniol (0.28 microg/cm(2)) was the most toxic, followed by beta-citronellol (0.29 microg/cm(2)), benzyl benzoate (9.58 microg/cm(2)), and DEET (18.23 microg/cm(2)). These results suggest that D. farinae and D. pteronyssinus may be controlled more effectively by the application of geraniol and beta-citronellol than benzyl benzoate and DEET. Furthermore, geraniol and beta-citronellol isolated from P. graveolens could be useful for managing populations of D. farinae and D. pteronyssinus. (+info)"Pelargonium" is not a term that has a medical definition. It is the name of a genus of flowering plants, commonly known as geraniums, which are often used in horticulture but do not have direct relevance to medical terminology or practice.
Bromoviridae is a family of positive-strand RNA viruses that infect plants. The name "Bromoviridae" comes from the type genus Brome mosaic virus (BMV), which was first isolated from brome grass. Viruses in this family have tripartite, single-stranded, positive-sense RNA genomes and are transmitted by aphids in a nonpersistent manner.
The genome of Bromoviridae viruses is divided into three segments (RNA1, RNA2, and RNA3) that encode different proteins. RNA1 and RNA2 encode the replicase protein, which is responsible for replication of the viral RNA. RNA3 encodes the movement protein, which facilitates cell-to-cell movement of the virus, and the coat protein, which protects the viral RNA and is involved in transmission by aphids.
Bromoviridae viruses cause a variety of symptoms in plants, including mosaic patterns on leaves, stunting, and necrosis. They are important pathogens of many crops, including vegetables, fruits, and ornamentals. Control measures for Bromoviridae viruses include the use of resistant plant varieties, cultural practices to reduce aphid populations, and chemical control of aphids.
I'm sorry for any confusion, but "Geraniaceae" is not a medical term. It is a taxonomic category in botany, referring to the family of flowering plants that includes geraniums, pelargoniums (often also called geraniums in common language), and several other related genera.
If you have any medical terms or concepts you'd like me to define or explain, I'd be happy to help!
Chenopodium quinoa is commonly known as "quinoa." It is not a true grass or cereal grain, but rather a pseudocereal that is closely related to beets and spinach. Quinoa is native to the Andean region of South America and has been cultivated and consumed for thousands of years by indigenous peoples in this region.
Quinoa is a highly nutritious food that is rich in protein, fiber, vitamins, minerals, and antioxidants. It contains all nine essential amino acids, making it a complete protein source. Quinoa is also gluten-free, which makes it a popular alternative to wheat and other grains for people with celiac disease or gluten intolerance.
The seeds of the quinoa plant are typically cooked and consumed as a grain, and they have a mild, nutty flavor and a fluffy texture when cooked. Quinoa can be used in a variety of dishes, including salads, pilafs, stir-fries, and breakfast cereals. It is also commonly used as a stuffing for vegetables or meat dishes.
Quinoa has gained popularity in recent years due to its numerous health benefits and versatility in cooking. It is now widely available in grocery stores and health food stores around the world.
Plant somatic embryogenesis techniques refer to the scientific methods used to induce and produce embryos from plant somatic cells, which are not involved in sexual reproduction. These techniques involve the culture of isolated plant cells or tissues on nutrient-rich media under controlled conditions that promote embryo development. The resulting embryos can be germinated into plants, which are genetically identical to the parent plant, a process known as clonal propagation.
Somatic embryogenesis techniques have various applications in plant biotechnology, including large-scale propagation of elite varieties, genetic transformation, and cryopreservation of plant genetic resources. The ability to produce embryos from somatic cells also has potential implications for understanding the fundamental mechanisms of plant development and evolution.
Anacardic acids are a type of organic compounds that are found in the sap, bark, and fruits of the Anacardium occidentale tree, also known as the cashew tree. These compounds are primarily phenolic lipids, which means they have both alcohol and acid components. They are known for their anti-inflammatory, antioxidant, and antimicrobial properties.
Anacardic acids are of interest in medical research due to their potential health benefits. Some studies suggest that they may help to prevent or treat conditions such as cancer, cardiovascular disease, and diabetes. However, more research is needed to confirm these effects and to determine the optimal doses and methods for using anacardic acids as therapeutic agents.
It's worth noting that some people may experience allergic reactions to anacardic acids or other compounds found in cashew nuts or other parts of the cashew tree. These reactions can range from mild skin irritation to severe anaphylaxis, so it's important to use caution when handling or consuming these substances.
Carmovirus is a genus of viruses in the family *Tombusviridae*, which infect plants. The name "Carmovirus" is derived from the initials of the plant it was first isolated from, **C**harlock **A**rtichoke **M**osaic **Virus**. These viruses have a single-stranded, positive-sense RNA genome and are transmitted by beetles and through mechanical means such as contaminated tools or hands.
Carmoviruses cause symptoms such as mosaic patterns, leaf curling, and stunting in infected plants. They replicate in the cytoplasm of host cells and form viral inclusion bodies called **X**-**bodies**. Examples of Carmoviruses include:
* Carmovirus (CarMV)
* Cardamine chlorotic fleck virus (CCFV)
* Poplar mosaic virus (PopMV)
* Turnip crinkle virus (TCV)
It's important to note that medical professionals and researchers in human health may not encounter the term "Carmovirus" frequently, as it primarily relates to plant virology.
'Plant infertility' is not a standard medical term, as it is typically used in the context of agriculture and plant biology. However, I can provide you with a general definition related to this context:
Plant infertility refers to the inability of a plant to produce viable seeds, fruits, or propagules due to various factors affecting its reproductive system. These factors may include genetic disorders, environmental stressors (such as extreme temperatures, drought, or nutrient deficiencies), pathogens, pests, or poor pollination. In some cases, assisted reproduction techniques, such as hand-pollination or embryo rescue, might be employed to overcome infertility issues in plants.