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All Topic Review Biography Peer Reviewed Entry Video Entry
Topic Review
Conserving Refugia
Refugia play an important role in contributing to the conservation of species and communities by buffering environmental conditions over time. 
  • 1.0K
  • 12 Apr 2021
Topic Review
Tissue-Specificity of Plant Circadian Clocks
The plant circadian clock has a pervasive influence on many aspects of plant biology and is proposed to function as a developmental manager. To do so, the circadian oscillator needs to be able to integrate a multiplicity of environmental signals and coordinate an extensive and diverse repertoire of endogenous rhythms accordingly. Recent studies on tissue-specific characteristics and spatial structure of the plant circadian clock suggest that such plasticity may be achieved through the function of distinct oscillators, which sense the environment locally and are then coordinated across the plant through both intercellular coupling and long-distance communication.
  • 1.0K
  • 31 Mar 2021
Topic Review
Stem/Leaf Anatomy of Aragoa (Plantaginaceae)
Aragoa is a shrubby genus endemic to páramo in the northern Andes representing the sister group to Plantago and Limosella. Stem and leaf structure of Aragoa corrugatifolia were studied to clarify the evolutionary pathways and ecological significance of their anatomical traits. Aragoa and Plantago share a non-fascicular primary vascular system, rayless wood and secondary phloem, and anomocytic stomata. Aragoa is distinctive from most Plantaginaceae in the presence of cortical aerenchyma and of helical thickenings in vessels. Its procambium emerges in the primary meristem ring as a continuous cylinder. The view on the ring meristem and procambial strands as developmental stages in the formation of a primary vascular system is not relevant for Aragoa, and probably for other Plantaginaceae. The raylessness is synapomorphic for the crown clade of Plantaginaceae comprising Aragoa, Littorella, Plantago, Veronica, Picrorhiza, Wulfenia, and Veronicastrum. The loss of rays is thought to be predetermined by procambium rather than by the vascular cambium. The extremely narrow vessels with helical thickenings are presumably adaptive to hydric and thermic conditions of páramo. Cortical aerenchyma is thought to be a response to the local hypoxia caused by the water retained by ericoid leaves. Trichomes on juvenile leaves are expected to be the traits of considerable taxonomic importance. 
  • 1.0K
  • 04 Sep 2021
Topic Review
Bioactive Compounds from Elaeodendron Genus
Elaeodendron is a genus of tiny trees, shrubs, vines, and herbs consisting of about 23 species. It is used in traditional medicine and has a wide range of pharmacological activities. From the plants in this genus, flavonoids, terpenoids, cardiac glycosides, and cardenolides have been isolated. Preclinical investigations have also revealed antiviral, anti-HIV, anticancer, antiproliferative, antioxidant, antifungal, anti-inflammation, cytotoxic, anti-plasmodial, anti-arthritic, antibacterial, and anti-diabetic activities. Bioactive substances found in Elaedendron that function in a variety of ways are related to these biological processes. 
  • 1.0K
  • 20 Feb 2023
Topic Review
Windstorms on Forests in Tropical
Windstorm is one of the destructive natural disturbances, but the scale-link extent to which recurrent windstorms influenced forests ecosystems is poorly understood in a changing climate across regions. We reviewed the synergistic impacts of windstorms on forests and assessed research trends and methodological approaches from peer-reviewed articles published from 2000 to 2020 in tropical (TRF), subtropical (SUF), and temperate (TEF) forests/zones, based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Overall, the majority of the reviewed studies were conducted in TRF (i.e., 40%), intermediate in SUF (i.e., 34%), and the lowest in TEF (i.e., 26%). Among the four levels of biological organization, the species-population and community-ecosystem levels had the highest number of study cases, while the molecular-cellular-individual and landscape levels had the lowest study cases in all forest types. Most of the articles reviewed dealt largely on tree mortality/survival and regeneration/succession for TRF, tree mortality/survival and species composition/richness/diversity for SUF, and stem density, gap dynamics, and regeneration/succession for TEF. However, research on the effects of windstorms on mycorrhizal symbioses, population genetics, and physiological adaptation, element fluxes via litterfall, litter decomposition, belowground processes, biological invasion, and tree health are less common in all forest types. Further, most of the studies were conducted in permanent plots but these studies mostly used observational design, while controlled studies are obviously limited. Consequently, more observational and controlled studies are needed on the topic reviewed, particularly studies at the molecular-cellular-individual and landscape levels, to help inform forest management decision-making about developing sustainable and resilient forests amid climate change.
  • 1.0K
  • 15 Dec 2020
Topic Review
Secondary Metabolites of Sarraceniaceae Family
Carnivorous plants have fascinated researchers and hobbyists for centuries because of their mode of nutrition which is unlike that of other plants. They are able to produce bioactive compounds used to attract, capture and digest prey but also as a defense mechanism against microorganisms and free radicals. Darlingtonia, Heliamphora and Sarracenia plants are rich in compounds with potential pharmaceutical and medical uses. These belong to several classes such as flavonoids, with flavonol glycosides being the most abundant, monoterpenes, triterpenes, sesquiterpenes, fatty acids, alkaloids and others. Some of them are well characterized in terms of chemical properties and biological activity and have widespread commercial applications. Sarraceniaceae species contain numerous substances with the potential to advance health. 
  • 1.0K
  • 14 Oct 2022
Topic Review
Heat Stress Tolerance in Cowpea
Heat stress is often described as a condition of high temperatures that are sufficient to cause permanent damage to plant processes, including shortening the time for photosynthetic contribution to seed production. Heat stress on most plants can impact functions through the direct effects of high tissue temperature or the indirect consequences of the high evaporative demand accompanying hot weather. Understanding the impact of heat stress is crucial for plant breeding because it relates to key adaptive, biochemical, morphological, physiological, and reproductive processes. Despite its ability to thrive in high-temperature environments, cowpea productivity can be hampered by heat stress, particularly when night air temperatures exceed 17 °C. The crop’s germplasm pool potentially possesses significant genetic variability that can be harnessed to breed for heat-tolerant varieties. 
  • 1.0K
  • 06 Mar 2024
Topic Review
Susceptibility Genes in Castanea sativa
Castanea sativa is one of the main multipurpose tree species valued for its timber and nuts. This species is susceptible to two major diseases, ink disease and chestnut blight, caused by Phytophthora spp. and Cryphonectria parasitica, respectively. The loss-of-function mutations of genes required for the onset of pathogenesis, referred to as plant susceptibility (S) genes, are one mechanism of plant resistance against pathogens. On the basis of sequence homology, functional domain identification, and phylogenetic analyses, we report for the first time on the identification of S-genes (mlo1, dmr6, dnd1, and pmr4) in the Castanea genus. The expression dynamics of S-genes were assessed in C. sativa and C. crenata plants inoculated with P. cinnamomi and C. parasitica. Our results highlighted the upregulation of pmr4 and dmr6 in response to pathogen infection. Pmr4 was strongly expressed at early infection phases of both pathogens in C. sativa, whereas in C. crenata, no significant upregulation was observed. The infection of P. cinnamomi led to a higher increase in the transcript level of dmr6 in C. sativa compared to C. crenata-infected samples. For a better understanding of plant responses, the transcript levels of defense genes gluB and chi3 were also analyzed.
  • 1.0K
  • 11 Jun 2021
Topic Review
Bioactive Compounds in Agricultural Plants
Plants continuously rely on light as an energy source and as the driver of many processes in their lifetimes. The ability to perceive different light radiations involves several photoreceptors, which in turn activate complex signalling cascades that ultimately lead to a rearrangement in plant metabolism as an adaptation strategy towards specific light conditions. This entry introduces the main classes of secondary metabolites and specifically focuses on the influence played by the different wavelengths on the content of these compounds in agricultural plants, because of their recognised roles as nutraceuticals.
  • 1.0K
  • 08 Aug 2021
Topic Review
Nematicidal Activity of Essential Oils
Essential oils (EOs) can be a large source of new food-safe and healthy nematicidal products, due to their strong activity on crop pathogens and pests, including phytoparasitic nematodes, as well as to their low environmental persistence.
  • 1.0K
  • 13 Aug 2021
Topic Review
Strigolactone-Mediated Bud Outgrowth
Strigolactones (SLs), being a novel class of phytohormone, are known to play a key role in branching decisions, where they act as a negative regulator of bud outgrowth. They can achieve this by modulating polar auxin transport to interrupt auxin canalisation, and independently of auxin by acting directly within buds by promoting the key branching inhibitor TEOSINTE BRANCHED1.
  • 1.0K
  • 17 Jan 2023
Topic Review
Protein-Based Biostimulants
Protein-based biostimulants (PBBs) are derived from the hydrolysis of protein-rich raw materials of plant and/or animal origins, usually by-products or wastes from agro-industries. The active ingredients (AIs) produced by hydrolysis have the capacity to influence physiological and metabolic processes in plants, leading to enhanced growth, nutrient and water-use efficiency, tolerance to abiotic and biotic stresses, and improved crop yield and quality.
  • 1.0K
  • 30 Dec 2022
Topic Review
Full-Length Transcriptome of Purslane
Purslane (Portulaca oleracea) first came from India and Iran and has spread around the world. It is a warm-climate, juicy annual plant spread around the world, belonging to the Portulacaceae family.
  • 1.0K
  • 13 Apr 2021
Topic Review
Seed Dormancy and Germination
Seed dormancy, defined as the inability of seeds to undergo germination under optimal conditions, played a crucial role in the evolution of flowering plants.
  • 1.0K
  • 19 Jan 2021
Topic Review
Neuroprotective Effects of Polyphenols in Neurodegenerative Diseases
It has been shown that polyphenols in various natural sources can provide curative effects against various brain diseases and disorders through neuroprotective effects. These neuroprotective effects are mainly attributed to its ability to cross the blood-brain barrier, remove reactive oxygen species, and cause chelation of metal ions. Polyphenols increase the concentration of neurotrophic factors and bind directly to the membrane receptors of these neurotrophic factors to modulate and activate the signaling cascades that allow the plasticity, survival, proliferation, and growth of neuronal cells, allowing better learning, memory, and cognition. Furthermore, polyphenols do not have serious adverse side effects from their consumption.
  • 1.0K
  • 12 Sep 2023
Topic Review
Direct Embryos in Cultured Anthers
Cassava is one of the most important sources of energy. To meet the growing demand, genetic improvement is of utmost importance. Its cross-pollinating nature limits the opportunity of exploitation of hybrid vigour and demands the development of homozygous lines through doubled-haploid technologies. The problems in callus mediated embryogenesis such as longer processing time and genetically unstable nature can be overcome by direct embryogenesis. Conditions to produce embryos directly from microspores in cultured anthers were optimized. The optimum stress pre-treatment condition was 40°C for 6 h after culturing the anthers in to the induction medium. For pro-embryo formation, 2% sucrose and 5 mg/l 2,4-Dichlorophenoxyacetic acid (2,4-D) or 1 mg/l 1-Naphthaleneacetic acid were optimum. Globular embryos were formed by sub-culturing pro-embryos into the medium with 0.5 mg/l 2,4-D and 5 mg/l 6-Benzylaminopurine after two weeks of culturing. Light microscopy of cultured anthers demonstrated the formation of multicellular structures and their further development into pro-embryos. Microscopic studies showed pro-embryos emerging through the damaged anther wall.  Mono-allelic banding in Simple Sequence Repeat (SSR) analysis indicated homozygous or haploid state in some of the originated embryos. The conditions optimized in this study were effective in early development of direct embryos after two weeks of culture initiation.  This is the first report of formation of direct embryos in cultured anthers of cassava.  
  • 1.0K
  • 09 Nov 2020
Topic Review
List of Wildflowers of Soldiers Delight
The Soldiers Delight Natural Environment Area, consists of about 1,900 acres (7.7 km2) of land in Owings Mills, Maryland, USA. Much of the area of Soldiers Delight contains a serpentine barren that contains a number of rare and endangered species of plants. The following list of herbaceous plants is based greatly on the work of Ed Uebel and comes from the publications by Fleming et al. 1995, Monteferrante 1973, Reed 1984, Wennerstrom 1995, and the unpublished data by Worthley 1955-1985.
  • 1.0K
  • 10 Oct 2022
Topic Review
CICA-17 Quinoa
Quinoa may be a promising alternative solution for arid regions, and it is necessary to test yield and mineral accumulation in grains under different soil types. Field experiments with Chenopodium quinoa (cv. CICA-17) were performed in Egypt in non-saline (electrical conductivity, 1.9 dS m−1) and saline (20 dS m−1) soils. Thirty-four chemical elements were studied in these crops. Results show different yields and mineral accumulations in the grains. Potassium (K), P, Mg, Ca, Na, Mn, and Fe are the main elements occurring in the quinoa grains, but their concentrations change between both soil types. Besides, soil salinity induced changes in the mineral pattern distribution among the different grain organs. Sodium was detected in the pericarp but not in other tissues. Pericarp structure may be a shield to prevent sodium entry to the underlying tissues but not for chloride, increasing its content in saline conditions. Under saline conditions, yield decreased to near 47%, and grain sizes greater than 1.68 mm were unfavored. Quinoa may serve as a complementary crop in the marginal lands of Egypt. It has an excellent nutrition perspective due to its mineral content and has a high potential to adapt to semi-arid and arid environments.
  • 1.0K
  • 08 Mar 2021
Topic Review
Peptide Phytohormones
Various plant peptide hormones play a role in the defense from pathogens and herbivores and also in the interaction with beneficial microorganisms. Some families of peptide phytohormones have exclusively protective functions and are among the components of plant immunity, whereas other members of peptide phytohormones mostly play a role in the regulation of plant growth, but can be also involved in the defense response or plant–microbe interactions.
  • 1.0K
  • 29 Oct 2021
Topic Review
Epidemics: Indigenous and Introduced Crops
Virus disease pandemics and epidemics that occur in the world’s staple food crops pose a major threat to global food security, especially in developing countries with tropical or subtropical climates. Moreover, this threat is escalating rapidly due to increasing difficulties in controlling virus diseases as climate change accelerates and the need to feed the burgeoning global population escalates. One of the main causes of these pandemics and epidemics is the introduction to a new continent of food crops domesticated elsewhere, and their subsequent invasion by damaging virus diseases they never encountered before.
  • 1.0K
  • 16 Dec 2020
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