- PublicaciónAcceso abiertoFirst record of Chlorophyllum molybdites (G. Mey.) Massee (Basidiomycota, Agaricales, Agaricaceae) from Bucaramanga, Department of Santander, Colombia(2022-05-09)Colombia is a megadiverse country with many macrofungi species. Despite their ecological, anthropological, and economic importance, the distribution of many macrofungal species is still scarcely known in this country. Chlorophyllum molybdites (G. Mey.) Massee is a poisonous macrofungus common in urban settings of tropical and subtropical regions. In Colombia it has only been reported in three of 32 departments. To fill this gap in knowledge we morphologically describe for the first time C. molybdites from the city of Bucaramanga, Department of Santander, extending the known distribution of this macrofungus in Colombia.
- PublicaciónAcceso abiertoProposal of a method to evaluate the in-situ oxidation of polyphenolic during the cocoa drying(2022-03-05)In this work, the oxidation of polyphenols during drying of cocoa beans by using microwaves (MWs), applied in an ON-OFF mode, was studied. Phenolic compounds were quantified in cocoa beans before and after drying. Total phenolics content was analyzed by using some analytical techniques such as Fourier transform infrared (FTIR) spectroscopy, and high-performance liquid chromatography (HPLC). To study the oxidation process in-situ, an innovative methodology was proposed based on the counting of the coloring of the polyphenols contained in the parenchyma cells of the cocoa beans (cotyledon). The level of coloration in the inner zone and the surface of the dried cocoa beans showed that degradation of polyphenol compounds during the drying does not obey to a transport mechanism (diffusion), but in-situ oxidative processes.
- PublicaciónAcceso abiertoArbuscular mycorrhizal fungal association boosted the arsenic resistance in crops with special responsiveness to rice plant(2022-01-05)Arsenic (As) is a potentially toxic metalloid classified as a group 1 carcinogen, released in the soil environment because of natural as well as different anthropogenic activities. The presence of excess As content in soil and irrigation water enhances the As accumulation in rice grains. Millions of people who consume these contaminated grains are exposed to severe health issues. Increased arsenic uptake causes oxidative stress in plants, which combats by inducing the expression of several genes and signaling the biosynthesis of various antioxidants and phytochelatins. As toxicity reduces crop productivity, so it's critical to improve plant growth in As-contaminated environments while minimizing metal translocation to grains. Arbuscular mycorrhiza fungi (AMF) is considered a sustainable way to tolerate As toxicity. Organic pollutants metabolism by AMF, degradation of these soil contaminants by AMF exudation enzymes, and elimination of the pollutants by plant uptake and accumulation are the principal mechanisms of AMF mediated bioremediation. However, plant responses are established to vary with the host plant and the species of AMF. In our review, we showed that understanding the community composition, diversity, and gene regulation of AMF in the rice ecosystem played a critical role in maximizing As uptake and their potential in sustainable rice and other crops production. It has been reviewed that AMF has the potential to survive in an extremely As toxic condition and it potentially aids to improve the tolerance level of host plants.
- PublicaciónAcceso abiertoActividad Acaricida In Vitro de Compuestos Sobre Schizotetranychus hindustanicus(Hirst), (Acari: Tetranychidae), Ácaro Hindú de los Cítricos(2022-02-01)El cultivo de lima Tahití(Citrus x latifolia Tanaka ex Q. Jiménez)ocupa un importante porcentaje dentro de la cadenacomercialde los cítricos en Colombia, pero es atacado por Schizotetranychus hindustanicus o ácarohindú, un fitófago que produce lesiones típicas en el haz de las hojas y frutos, caracterizadas por manchas blanquecinas circulares que corresponden a las telarañas que teje la hembra y que le restan valor estético al fruto y a su comercialización. El objetivo del presente estudio consistió en evaluar in vitrolos efectos acaricidas de distintos compuestos en tres tiempos de contacto sobre poblaciones del ácaro.Se evaluó extracto oleaginoso de Neem (Azadirachta indica)al 1,0%, azufre micronizado al 0,5%, extracto acuoso de Azadirachtina 0,4%, filtrado de caldo de ceniza al 15 %. Como control positivo se utilizó Abamectina al 0,2%, producto reconocido por su efecto acaricida, y se usó agua destilada como control negativo. Se evidenció que los tratamientos más efectivos fueronelextracto oleaginoso de Neem-A. indicaal1,0%, azufre micronizado al 0,5%, y Abamectina al 0,2% con valores de mortalidad del 96,4;97,9 y100 % a las 72 horasrespectivamente. Los resultados permiten sugerir el uso de compuestos naturales a base de Azadirachta indicaen soluciones oleaginosas para el control deesta plaga, pues no afectan el ecosistema a la vez que no se han reportado resistencias del fitófago por su uso.
- PublicaciónAcceso abiertoActinobacteria-enhanced plant growth, nutrient acquisition, and crop protection: Advances in soil, plant, and microbial multifactorial interactions(2022-02-05)Agricultural areas of land are deteriorating every day owing to population increase, rapid urbanization, and industrialization. To feed today's huge populations, increased crop production is required from smaller areas, which warrants the continuous application of high doses of inorganic fertilizers to agricultural land. These cause damage to soil health and, therefore, nutrient imbalance conditions in arable soils. Under these conditions, the benefits of microbial inoculants (such as Actinobacteria) as replacements for harmful chemicals and promoting ecofriendly sustainable farming practices have been made clear through recent technological advances. There are multifunctional traits involved in the production of different types of bioactive compounds responsible for plant growth promotion, and the biocontrol of phytopathogens has reduced the use of chemical fertilizers and pesticides. There are some well-known groups of nitrogen-fixing Actinobacteria, such as Frankia, which undergo mutualism with plants and offer enhanced symbiotic trade-offs. In addition to nitrogen fixation, increasing availability of major plant nutrients in soil due to the solubilization of immobilized forms of phosphorus and potassium compounds, production of phytohormones, such as indole-3-acetic acid, indole-3-pyruvic acid, gibberellins, and cytokinins, improving organic matter decomposition by releasing cellulases, xylanase, glucanases, lipases, and proteases, and suppression of soil-borne pathogens by the production of siderophores, ammonia, hydrogen cyanide, and chitinase are important features of Actinobacteria useful for combating biotic and abiotic stresses in plants. The positive influence of Actinobacteria on soil fertility and plant health has motivated us to compile this review of important findings associated with sustaining plant productivity in the long run.