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Topic Review
Alsophila Dealbata
Alsophila dealbata, synonym Cyathea dealbata, commonly known as the silver fern or silver tree-fern, or as ponga /ˈpɒŋə/ or punga /ˈpʌŋə/ (from Māori kaponga or ponga), is a species of medium-sized tree fern, endemic to New Zealand. The fern is usually recognisable by the silver-white colour of the under-surface of mature fronds. It is a symbol commonly associated with the country both overseas and by New Zealanders themselves.
  • 1.8K
  • 02 Nov 2022
Topic Review
Domestication in the Neotropics
Charles Darwin used domestication as a metaphor for natural selection because everyone is familiar with the term. Since Darwin, domestication has become a major topic of research, both to help understand evolution, as Darwin did, and to understand how human societies came to dominate the world, which also interested Darwin. However, Darwin did not define the term, which has allowed students of domestication, such as geneticists, archaeologists and others, to tailor their definitions to their own objectives. Even our grammar influences the way we interpret simple phrases about domestication ( p. xiv), as we tend to put ourselves, as individuals or the human collective, in charge. As Darwin pointed out, however, the long history of human interaction with plants and animals that resulted in the domestication of some of them was influenced more by unconscious selection than conscious selection. Only when considering the latter type of selection, which Darwin called methodical selection, can we affirm that humans are in charge, and even then unintended consequences are common. Nonetheless, especially when used in studies to understand how humans came to dominate the world, definitions often assume that humans are in control, which is unlikely at the beginning of human interactions with plants and animals. As pointed out by Dolores Piperno and Deborah Pearsall ( p. 6), clear definitions of concepts are extremely important when discussing domestication and the food production systems in which many domesticates are grown or raised. Melinda Zeder reviewed a set of definitions to highlight their differences and theoretical frameworks, and emphasized that definitions for plants and animals are often quite different. Clement et al. prepared a short list of definitions for plant domestication since Zeder. Full definitions can help identify nuances that place human culture within Nature, as occurs in most Neotropical ontologies, rather than outside, which is typical of ideas of being in charge. We think that returning to a dictionary is also an appropriate exercise to explore definitions, especially as the definitions in Zeder and Clement et al. were designed by their authors to meet their own objectives, the majority of which are associated with identifying changes in morphology or genetics that prove that human selection resulted in a response. We will use the 1989 edition of the Oxford English Dictionary (OED), whose first edition was being researched and published at the same time that Darwin was writing. The verb domesticate comes from the Latin domesticäre – to dwell in a house, to accustom. The house is the center of the domus, the Latin root of domesticäre. The OED definitions include: “1.a. To make, or settle as, a member of a household; to cause to be at home; to naturalize. 1.b. To make to be or to feel ‘at home’; to familiarize. 2. To make domestic; to attach to home and its duties. 3. To accustom (an animal) to live under the care and near the habitations of man; to tame or bring under control; to civilize. 4. To live familiarly or at home (with); to take up one's abode.” It follows that the noun domestication is “the action of domesticating, or the condition of being domesticated” (OED), i.e., both the process itself and the results of the process. These definitions are about humans, who domesticate each other in their houses, with their associated gardens, orchards, pastures, woodlots, agroforests, and adjacent managed forests. Hence, the house and the surrounding landscape comprise the domus , until humans started living in cities or more recently in apartments. Animals are recognized in one of the definitions as being domesticated in the domus also, and it was Darwin who included plants. From these definitions, domestication is clearly anthropocentric, i.e., it is about us humans. Note that only one definition mentions control.  What are the human behaviors involved? Two are explicit in the definitions: care (of the occupants of the domus) and duty (the tasks of caring for the domus and its occupants). Two are implicit. Selection – since humans are selective about what is brought into the domus. The fact that selection is implicit, rather than explicit, may be why Darwin adopted domestication as his metaphor for natural selection. Accumulation – as people and animals are brought into the domus, both from nearby (familiarize) and far away (naturalize). As Darwin recognized, humans like variety, which can be seen in most gardens and even more clearly in swiddens. The definitions above are about both organisms (humans, animals, plants) and the domus. Most current definitions of domestication concentrate one behavior (selection), but care and accumulation are just as important.
  • 1.7K
  • 04 Mar 2021
Topic Review
Morphological Plasticity of Leaves
Plants adapt to environmental changes by regulating their development and growth. As an important interface between plants and their environment, leaf morphogenesis varies between species, populations, or even shows plasticity within individuals. Leaf growth is dependent on many environmental factors, such as light, temperature, and submergence. Phytohormones play key functions in leaf development and can act as molecular regulatory elements in response to environmental signals. In this review, we discuss the current knowledge on the effects of different environmental factors and phytohormone pathways on morphological plasticity and intend to summarize the advances in leaf development. In addition, we detail the molecular mechanisms of heterophylly, the representative of leaf plasticity, providing novel insights into phytohormones and the environmental adaptation in plants.
  • 1.7K
  • 19 May 2021
Topic Review
Essential Oils and Terpenoids Effects
Weeds are one of the major constraints in crop production affecting both yield and quality. The excessive and exclusive use of synthetic herbicides for their management is increasing the development of herbicide-resistant weeds and is provoking risks for the environment and human health. Therefore, the development of new herbicides with multitarget-site activity, new modes of action and low impact on the environment and health are badly needed. The study of plant–plant interactions through the release of secondary metabolites could be a starting point for the identification of new molecules with herbicidal activity. Essential oils (EOs) and their components, mainly terpenoids, as pure natural compounds or in mixtures, because of their structural diversity and strong phytotoxic activity, could be good candidates for the development of new bioherbicides or could serve as a basis for the development of new natural-like low impact synthetic herbicides. EOs and terpenoids have been largely studied for their phytotoxicity and several evidences on their modes of action have been highlighted in the last decades through the use of integrated approaches.
  • 1.7K
  • 25 Nov 2020
Topic Review
Perovskia Atriplicifolia
Perovskia atriplicifolia (/pəˈrɒvskiə ætrɪplɪsɪˈfoʊliə/), commonly called Russian sage, is a flowering herbaceous perennial plant and subshrub. Although not a member of Salvia, the genus of other plants commonly called sage, it is closely related to them. It has an upright habit, typically reaching 0.5–1.2 m tall (1.6–3.9 ft), with square stems and grey-green leaves that yield a distinctive odor when crushed. It is best known for its flowers. Its flowering season extends from mid-summer to late October, with blue to violet blossoms arranged into showy, branched panicles. It is native to the steppes and hills of southwestern and central Asia. Successful over a wide range of climate and soil conditions, it has since become popular and widely planted. Several cultivars have been developed, differing primarily in leaf shape and overall height; 'Blue Spire' is the most common. This variation has been widely used in gardens and landscaping. P. atriplicifolia was the Perennial Plant Association's 1995 Plant of the Year, and the 'Blue Spire' cultivar received the Award of Garden Merit from the Royal Horticultural Society. The species has a long history of use in traditional medicine in its native range, where it is employed as a treatment for a variety of ailments. This has led to the investigation of its phytochemistry. Its flowers can be eaten in salads or crushed for dyemaking, and the plant has been considered for potential use in the phytoremediation of contaminated soil.
  • 1.7K
  • 01 Nov 2022
Topic Review
Histone Acetyltransferase GCN5
Transcription of protein-encoding genes starts with forming a pre-initiation complex comprised of RNA polymerase II and several general transcription factors. To activate gene expression, transcription factors must overcome the repressive chromatin structure, which is accomplished with multiprotein complexes. Histone Acetyl Transferases (HAT) catalyze acetylation of specific lysine residues in histone N-tails, which are involved in transcriptional regulation and other nuclear processes. HATs are parts of large multiprotein complexes, like the SAGA complex, where their activity is enhanced, and their substrate specificity is altered. The whole complex is recruited to target sequences on the genome with other components involved in protein-protein interactions. A prototypical HAT which acts as a transcriptional adaptor is known as General Control Nonrepressed protein 5 (GCN5), first identified in Saccharomyces cerevisiae. GCN5 was defined biochemically as the first transcription-linked HAT with specificity for histone H3 lysine 14 (H3K14). However, GCN5 could also acetylate additional histone lysine residues, such as H3K9, H3K18, H3K23, H3K27, H3K36, other histones such as H4 and H2B and non-histone nuclear proteins.  In Arabidopsis, GCN5 is required for many developmental processes such as leaf development, apical dominance, root meristem activity, inflorescence, floral meristem function and flower fertility. 
  • 1.7K
  • 10 Feb 2021
Topic Review
Interactions of Gibberellins with Phytohormones
Gibberellins are amongst the main plant growth regulators. Discovered over a century ago, the interest in gibberellins research is growing due to their current and potential applications in crop production and their role in the responses to environmental stresses. The complex interrelations between gibberellins and other plant growth regulators are described, providing an intricate network of interactions that ultimately drives towards precise and specific gene expression. Thus, genes and proteins identified as being involved in gibberellin responses in model and non-model species are highlighted. Furthermore, the molecular mechanisms governing the gibberellins’ relation to stress responses are also depicted.
  • 1.7K
  • 21 Apr 2022
Topic Review
Tagetes (Asteraceae)
The genus Tagetes, which includes plants known as ‘marigolds’, belongs to the Asteraceae family and contains more than 50 cultivated and wild species. Marigolds are native to America, but several species are naturalised in Africa, Asia, and Europe. Plants of the genus Tagetes are amongst the most widespread garden flowers worldwide. Marigolds are popular amongst gardeners due to their easy cultivation, wide adaptability, low demands for ecological and technological factors, and flower production throughout the year.
  • 1.7K
  • 21 Apr 2022
Topic Review
Heme Biosynthesis
Heme biosynthesis is essential for almost all living organisms. Despite its conserved function, the pathway’s enzymes can be located in a remarkable diversity of cellular compartments in different organisms. This location does not always reflect their evolutionary origins, as might be expected from the history of their acquisition through endosymbiosis. Instead, the final subcellular localization of the enzyme reflects multiple factors, including evolutionary origin, demand for the product, availability of the substrate, and mechanism of pathway regulation. Chromera velia is a coral-associated alga bearing complex rhodophyte-derived plastid with a peculiar tetrapyrrole pathway. It synthesizes ALA using heterotrophic C4 path (same as apicomplexan parasites), which additionally supplies chlorophyll for photosystems. Using a combination of bioinformatics and experimental approaches, we investigated localizations of heme pathway enzymes in C. velia. Our data show that the pathway very likely starts in the mitochondrion, with the remaining enzymes located in the plastid. We demonstrate that the proteins are targeted to various cellular compartments by stringent translocon mechanisms that are not universal even for evolutionarily related organisms.
  • 1.7K
  • 08 Jul 2021
Topic Review
Hydrogenases in Plants
Hydrogenases catalyze the reversible oxidation of H2, and are found in many organisms, including plants. One of the cellular effects of H2 is the selective removal of reactive oxygen species (ROS) and reactive nitrogen species (RNS), specifically hydroxyl radicals and peroxynitrite. Therefore, the function of hydrogenases and the action of H2 needs to be reviewed in the context of the signalling roles of a range of redox active compounds. Enzymes can be controlled by the covalent modification of thiol groups, and although motifs targeted by nitric oxide (NO) can be predicted in hydrogenases sequences it is likely that the metal prosthetic groups are the target of inhibition.
  • 1.7K
  • 25 Mar 2021
Topic Review
Ziziphus nummularia Phytoconstituents and Pharmacological Properties
The genus Ziziphus of the Rhamnaceae family contains over 58 accepted species of thorny shrubs and small trees growing mostly in arid and semi-arid regions. Species of this genus are traditionally known for their health benefits, nutritional values, and therapeutic properties, as described by various cultures around the world, specifically in India, Pakistan, China and the Middle East.
  • 1.7K
  • 23 Feb 2023
Topic Review
Abiotic Stress in Rice
Rice (Oryza sativa L.), a species of Poaceae, is a ubiquitous staple food worldwide, offering vital nutrients, including carbohydrates, thiamin, folate, calcium, iron, pantothenic acid, and energy.
  • 1.7K
  • 04 Dec 2023
Topic Review
Vitro Plant Regeneration
Plants generally have the highest regenerative ability because they show a high degree of developmental plasticity. Although the basic principles of plant regeneration date back many years, understanding the cellular, molecular, and physiological mechanisms based on these principles is currently in progress. In addition to the significant effects of some factors such as medium components, phytohormones, explant type, and light on the regeneration ability of an explant, recent reports evidence the involvement of molecular signals in organogenesis and embryogenesis responses to explant wounding, induced plant cell death, and phytohormones interaction. However, some cellular behaviors such as the occurrence of somaclonal variations and abnormalities during the in vitro plant regeneration process may be associated with adverse effects on the efficacy of plant regeneration. A review of past studies suggests that, in some cases, regeneration in plants involves the reprogramming of distinct somatic cells, while in others, it is induced by the activation of relatively undifferentiated cells in somatic tissues. However, this review covers the most important factors involved in the process of plant regeneration and discusses the mechanisms by which plants monitor this process.
  • 1.7K
  • 02 Nov 2020
Topic Review
Rhamnus alaternus Plant
Rhamnus alaternus, is a wild-growing shrub, belonging to the Rhamnaceae family. Widely distributed in the Mediterranean basin, R. alaternus is used in the usual medicine in numerous countries, mostly Tunisia, Algeria, Morocco, Spain, France, Italy, and Croatia. A large number of disorders including dermatological complications, diabetes, hepatitis, and goiter problems can be treated by the various parts of R. alaternus (i.e., roots, bark, berries, and leaves). Several bioactive compounds were isolated from R. alaternus, including flavonoids, anthocyanins, and anthraquinones, and showed several effects such as antioxidant, antihyperlipidemic, antigenotoxic, antimutagenic, antimicrobial, and antiproliferative.
  • 1.7K
  • 16 Jun 2022
Topic Review
Monarda Species
The genus Monarda (family Lamiaceae) contains 22 species of which three are native to southern Alabama, M. citriodora, M. fistulosa, and M. punctata. Several species of Monarda have been used in traditional medicines of Native Americans, and this present study is part of an ongoing project to add to our understanding of Native American pharmacopeia.
  • 1.7K
  • 11 Mar 2021
Topic Review
Antioxidant/Antimicrobial Properties of Camellia sinensis
Camellia sinensis is the most consumed beverage worldwide. It contains a wide variety of secondary metabolites, such as alkaloids, saponins, tannins, catechins, and polyphenols, generated through a condensation reaction of cinnamic acid with three malonyl-CoA groups. In addition to the metabolic processes occurring within this plant, there are also some plant-associated bacterial endophytes. These bacteria reside in the living tissues of the host plants without causing any harmful effect to them, thereby stimulating secondary metabolite production with a diverse range of biological effects. 
  • 1.7K
  • 17 Jun 2021
Topic Review
Essential Oil Extracted from Lavandula dentata L.
An essential oil (EO) is a concentrated hydrophobic liquid containing volatile, easily evaporated at normal temperatures, chemical compounds isolated from plants. Essential oils are also known as volatile oils, ethereal oils, aetheroleum, or simply as the oil of the plant, from which they were extracted. EOs of various species of Lavandula dentata (Lamiaceae) have a broad range of biological effects including sedative, antibacterial, antifungal, antidepressant, antioxidant and anti-inflammatory properties.
  • 1.7K
  • 29 Mar 2022
Topic Review
Agastache mexicana
Mexico is the center of origin of the species popularly known as toronjil.  its use and commercialization for traditional Mexican medicine make it the most important member of the Agastache genus in Mexico. The species Agastache mexicana divides into two subspecies, based on anatomical characteristics and chemical composition: red lemon balm, Agastache mexicana Linton & Epling subspecies mexicana, and white toronjil, Agastache mexicana subspecies xolocotziana Bye, E.L. Linares & Ramamoorthy.
  • 1.7K
  • 22 Nov 2021
Topic Review
Exploitation and Benefits Derived from Bivalves
The windowpane oyster Placuna placenta lives in brackish coastal waters and has long been economically important to the Philippines because of its durable and translucent shell, which is used as a glass substitute and material for making windowpanes and handicrafts. There has been considerable degradation of the P. placenta fishery over the past. 
  • 1.7K
  • 11 Oct 2023
Topic Review
Capsaicinoids and Capsiate in Pepper
Capsaicinoids and capsinoids, which are bioactive compounds of interest, are  responsible for the level of pungency of chili peppers, which is one of their most important commercial traits. Both capsaicinoids and capsinoids have received great attention from consumers because of their extensive pharmacological and physiological effects, i.e., antitumor, antioxidant, antiobesity, anti-inflammatory, and analgesic.
  • 1.7K
  • 09 Nov 2020
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