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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.
  • 1.1K
  • 08 Aug 2021
Topic Review
Interaction of Chromolaena odorata with the Natural Enemy
Chromolaena odorata (L.) R.M. King & H. Robinson is native to tropical America, and has naturalized in many other countries in tropical Asia, Austria, and West Africa. The species often forms dense thickets and reduces the native species diversity and population in the invasive ranges. The species is also considered as a noxious weed in agriculture fields, and listed in the 100 of the world’s worst invasive alien species. The interaction between the invasive plants and their natural enemies such as herbivores and pathogens, is one of the important factors for the naturalization of the invasive plants. The population of C. odorata is controlled by many insects and pathogens in its native ranges. More than 200 species of the herbivores were counted in the native ranges of C. odorata, and 25% of them are specific species in the native ranges. There may be fewer specific herbivores in the invasive ranges. In fact, very few specific insect species for C. odorata in the invasive range (South Africa) were counted.
  • 1.1K
  • 14 Feb 2023
Topic Review
Phytoplasma Diseases in Middle East
Phytoplasmas that are associated with fruit crops, vegetables, cereal and oilseed crops, trees, ornamental, and weeds are increasing at an alarming rate in the Middle East. Up to now, fourteen 16Sr groups of phytoplasma have been identified in association with more than 164 plant species in this region. Peanut witches’ broom phytoplasma strains (16SrII) are the prevalent group, especially in the south of Iran and Gulf states, and have been found to be associated with 81 host plant species. In addition, phytoplasmas belonging to the 16SrVI, 16SrIX, and 16SrXII groups have been frequently reported from a wide range of crops. On the other hand, phytoplasmas belonging to 16SrIV, 16SrV, 16SrX, 16SrXI, 16SrXIV, and 16SrXXIX groups have limited geographical distribution and host range. Twenty-two insect vectors have been reported as putative phytoplasma vectors in the Middle East, of which Orosius albicinctus can transmit diverse phytoplasma strains. Almond witches’ broom, tomato big bud, lime witches’ broom, and alfalfa witches’ broom are known as the most destructive diseases. 
  • 1.1K
  • 30 Mar 2021
Topic Review
Benefits of Insect Pollination in Brassicaceae
Cultivated Brassicaceae attract a wide variety of pollinators. In both self-compatible and self-incompatible crop species, meta-analysis indicates that seed yield (Y), silique set (SQS), number of siliquae/plant (NSQ), and the number of seeds/silique (NSSQ) increase when plants are insect-pollinated compared to when there is no insect pollination. The weight of seeds (WS), however, increased in self-incompatible species but not in self-compatible ones as a result of insect pollination. Overall, the percentage of studies showing a positive effect of insect pollination on yield parameters was higher in self-incompatible than in self-compatible species. It was shown that the ability of self-compatible species to reproduce does not fully compensate for the loss of yield benefits in the absence of insect pollination. 
  • 1.1K
  • 31 Mar 2022
Topic Review
TYLCV Infection of Tomatoes
Tomato cultivation is threatened by environmental stresses (e.g., heat, drought) and by viral infection (mainly viruses belonging to the tomato yellow leaf curl virus family—TYLCVs). Unlike many RNA viruses, TYLCV infection does not induce a hypersensitive response and cell death in tomato plants. One of the major effects caused by TYLCV infection of tomato is a decrease in the activation of stress response proteins and metabolites to avoid an acute deleterious plant response, which may impair virus replication. Instead of severe, sometimes lethal response for most plant cells, TYLCV promotes the development of a protective homeostasis response in plants exposed to prolonged environmental stresses, favoring the survival of the plant. The down-regulation of stress proteins and metabolites coincides with the stabilization of their patterns, particularly in tomatoes resistant to TYLCV. These stable patterns are maintained not only in shoot, but also in roots of virus-infected tomatoes. Whether fruit production of pre-inoculation of R-TYLCV tomato seedlings in field and greenhouses located in hot and dry countries provides a solution, even partial, to global warming, remains to be analyzed on a large scale. This routine, adapted to tomato genotype, soil and climate, may help reduce drastically the amount of water used for irrigation by artificially alternating long periods of drought with short periods of irrigation.
  • 1.1K
  • 29 Nov 2022
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. 
  • 1.1K
  • 20 Feb 2023
Topic Review
Sesquiterpene Lactones in Medicine
Sesquiterpene lactones (SL), characterized by their high prevalence in the Asteraceae family, are one of the major groups of secondary metabolites found in plants. Researchers from distinct research fields, including pharmacology, medicine, and agriculture, are interested in their biological potential. With new SL discovered in the last years, new biological activities have been tested, different action mechanisms (synergistic and/or antagonistic effects), as well as molecular structure–activity relationships described.
  • 1.1K
  • 18 Feb 2022
Topic Review
5-Aminolevulinic Acid Priming to Enhance Plant Tolerance
Priming is an adaptive strategy that improves plant defenses against biotic and abiotic stresses. Stimuli from chemicals, abiotic cues, and pathogens can trigger the establishment of priming state. Priming with 5-aminolevulinic acid (ALA), a potential plant growth regulator, can enhance plant tolerance to the subsequent abiotic stresses, including salinity, drought, heat, cold, and UV-B. However, the molecular mechanisms underlying the remarkable effects of ALA priming on plant physiology remain to be elucidated.
  • 1.1K
  • 26 Jan 2022
Topic Review
Humulus lupulus L. By-Products
Hops (Humulus lupulus L.) are known worldwide as a raw material in beer production due their flavor and preservative values. The beneficial properties of the plant have been mostly associated with the female hop inflorescences (cones), which is also the part used in the brewing industry. However, some studies indicate the presence of compounds associated with health benefits in the vegetative parts of hops or small-caliber cones, which discarded in hop collection. Moreover, large quantities of by-products remain in the forms of spent grains and spent hops/hot trub and are produced by breweries raising environmental and economic sustainability concerns.
  • 1.1K
  • 22 Dec 2022
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.
  • 1.1K
  • 11 Jun 2021
Topic Review
Cytokinin and Auxin in DNSO
The role of CK and auxin signalization is central to the entire process of DNSO, whereby the early stages of DNSO are dominated by auxin and the later stages by CK signaling. Taking into account the early observation by Skoog and Miller that a high auxin/CK ratio stimulates the development of roots, while a high CK/auxin ratio is favorable to the development of shoot tissue, the general need for a sequence of two regeneration media can be explained by the differences in morphogenic requirements between early and late stages of DNSO. In the early stages, a high auxin/CK ratio is required not only for the development of calli but also of lateral root-like primordia within the calli; later, a high CK/auxin ratio will be required to convert the developmental fate of these primordia into taking on a shoot identity.
  • 1.1K
  • 18 Aug 2021
Topic Review
Identification of Secondary Metabolites in Medicinal Orchids
The secondary metabolites present in medicinal orchids are diverse and possess a vast array of biological activities. They represent valuable raw materials for modern pharmaceuticals and clinical medicine and have tremendous potential for future development. A systematic collation of secondary metabolites’ composition and a summary of the biological activities of medicinal orchids represent a crucial step in unlocking the potential of these valuable resources in drug development.
  • 1.1K
  • 24 Jul 2023
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. 
  • 1.1K
  • 06 Mar 2024
Topic Review
Secondary Metabolites Produced by Plant Growth-Promoting Bacterial Endophytes
There is an increasing interest in the use of beneficial microorganisms as alternatives to chemically synthesized or plant-derived molecules to produce therapeutic agents. Bacterial endophytes are plant-associated microorganisms that can colonize different parts of living plants without causing any diseases. Diverse endophytic bacteria possess the ability to synthesize a wide range of secondary metabolites with unique chemical structures that have been exploited for their anti-microbial, antiviral, anti-cancer, and anti-inflammatory properties. Additionally, production of these bioactive compounds can also benefit the host plant as they may play a significant role in a plant’s interaction with the environment for adaptation and defense.
  • 1.1K
  • 14 Nov 2022
Topic Review
miRNAs in Barley Physiology and Stress Responses
MicroRNAs (miRNAs) are important players in post-transcriptional gene expression regulation in multicellular species. miRNAs can modify/decrease the expression of fully or partially complementary mRNA molecules. Plant miRNAs are powerful regulators of gene expression at the post-transcriptional level, which was repeatedly proved in several model plant species. miRNAs are considered to be key regulators of many developmental, homeostatic, and immune processes in plants. 
  • 1.1K
  • 02 Dec 2022
Topic Review
Types of Wheat Resistance to Leaf Rust
Due to the global warming and dynamic changes in pathogenic virulence, leaf rust caused by Puccinia triticina has greatly expanded its epidermic region and become a severe threat to global wheat production. Leaf rust, caused by biotrophic fungal pathogen Puccinia triticina Erikss., is one of the most wide-spread and severe diseases in wheat all over the world.
  • 1.1K
  • 01 Mar 2023
Topic Review
Cowpea Cultivation Constraints and Breeding in Europe
Cowpea (Vigna unguiculata (L.) Walp.) is a legume with a constant rate of cultivation in Southern European countries. Consumer demand for cowpea worldwide is rising due to its nutritional content, while Europe is attempting to reduce the deficit in the production of pulses and invest in new, healthy food market products. Cultivation and utilization of cowpea plant genetic resources (PGRs), including landraces, in breeding programmes with the implementation of classical and modern breeding techniques could promote sustainability of cropping systems and alleviate the negative effects of climate change.
  • 1.1K
  • 06 Apr 2023
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.
  • 1.1K
  • 12 Sep 2023
Topic Review
Biodiversity and Ferula gummosa
Ferula gummosa (FG) is named Barijeh, Balijeh, Ghasni and Barzard in Persian. It belongs to the Ferula genus in the family Apiaceae. This family with at least 112 genera contains aromatic plants with hollow stems and umbrella inflorescences. The genus Ferula contains 170 species and is extensively distributed from Central Asia to South Africa. FG is one of the industrial, medicinal and forage valuable assets in Iran. As a dominant or associated species, it forms a wide range of plant types in mountainous areas. The phenological stages of the FG plant are as follows: seed germination starts from late March to early April, and vegetative growth begins from the second half of April and continues until the first half of July.
  • 1.1K
  • 27 Jul 2021
Topic Review
Scorzonera L.
Scorzonera L. is a genus in the Cichorieae tribe of the Asteraceae family.  It is spread mostly in central and southern parts of Europe, Eurasia, and Africa in arid areas. The genus comprises approximately 180–190 species.
  • 1.1K
  • 30 Jun 2021
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