A review of techniques for detecting Huanglongbing (greening) in citrus

Abstract Huanglongbing (HLB) is the most destructive disease of citrus worldwide. Monitoring of health and detection of diseases in trees is critical for sustainable agriculture. HLB symptoms are virtually the same wherever the disease occurs. The disease is caused by Candidatus Liberibacter, vectored by the psyllids Diaphorina citri Kuwayama and Trioza erytreae. Electron microscopic technique was the first method for HLB detection. Nowadays, scientists are working on the development of new techniques for a rapid HLB detection as there is no sensor commercially accessible for real-time assessment of health conditions in trees. Currently, exploration is the most widely used mechanism for monitoring HLB, which is an expensive, labor-intensive and time-consuming process. Molecular techniques such as polymerase chain reaction are used for the identification of HLB disease, which requires detailed sampling and processing procedures. Furthermore, investigations are ongoing in spectroscopic and imaging techniques, profiling of plant volatile organic compounds and isothermal amplification. This study recognizes the need for developing a rapid, cost-effective, and reliable health monitoring sensor that would facilitate advancements in HLB disease detection. This paper compares the benefits and limitations of these potential methods for HLB detection.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

The Herbicidal Activity of Nano- and MicroEncapsulated Plant Extracts on the Development of the Indicator Plants <i>Sorghum bicolor</i> and <i>Phaseolus vulgaris</i> and Their Potential for Weed Control

Weeds decrease yield in crops through competition for water, nutrients, and light. Due to the circumstances mentioned above and the challenge of the emergence of herbicide-resistant weeds, developing sustainable alternatives becomes imperative. Plant extracts formulated into nano- and micro-encapsulates (NPs) emerge as a viable option for weed management. The objectives of this study were to identify phytochemical compounds within the ethanolic extracts of Carya illinoinensis, Ruta graveolens, and Solanum rostratum; determine their pre-emergence herbicidal activity on the indicator plants Sorghum bicolor and Phaseolus vulgaris; produce and characterize NPs with plant extracts; and assess their phytotoxicity under greenhouse conditions. The extracts were provided by Greencorp Biorganiks de México. Phytochemicals were identified through colorimetric assays and HPLC-MS, while pre-emergence tests were conducted in vitro, assessing concentrations of 12.5, 25, and 50% for each extract. NPs were synthesized using the ionotropic pre-gelation method, with size, zeta potential, and encapsulation efficiency (EE) being characterized. Finally, post-emergence tests were carried out in a greenhouse with seedlings. Compounds belonging to the hydroxycinnamic acid, flavonol, methoxyflavonol, hydroxybenzoic acid, methoxyflavone, tyrosol, stilbene, and lignan families were identified in all extracts. The pre-emergence herbicidal activity was observed for all extracts, with germination percentages ranging from 0 to 41% in both indicator plants. NPs exhibited sizes between 290 and 345 nm, zeta potentials ranging from −30 to −35 mV, and EE up to 94%. Finally, enhanced herbicidal activity was observed with plant extract NPs, with the species S. bicolor being more susceptible. NPs containing plant extracts are a viable option for bioherbicide production; however, continued research is necessary to refine formulations and enhance efficacy

Phytochemical Characterization of <i>Phoradendron bollanum</i> and <i>Viscum album</i> subs. <i>austriacum</i> as Mexican Mistletoe Plants with Antimicrobial Activity

In Mexico, mistletoes have several applications in traditional medicine due to the great variety of compounds with biological activities that have not been characterized to date. The goals of the present study are to analyze the composition of minerals and phytochemical compounds in Mexican mistletoes Phoradendron bollanum and Viscum album subs. austriacum qualitatively and quantitatively, identify the compounds using HPLC-MS, and assess the antimicrobial potential in phytopathogenic microorganism control. Mineral content was evaluated with X-ray fluorescence. Three types of extracts were prepared: ethanol, water, and aqueous 150 mM sodium chloride solution. Characterization was carried out using qualitative tests for phytochemical compound groups, analytical methods for proteins, reducing sugars, total phenol, flavonoids quantification, and HPLC-MS for compound identification. The antimicrobial activity of mistletoe’s liquid extracts was evaluated by microplate assay. K and Ca minerals were observed in both mistletoes. A qualitative test demonstrated alkaloids, carbohydrates, saponins, flavonoids, tannins, and quinones. Ethanolic extract showed flavonoids, 3845 ± 69 and 3067 ± 17.2 mg QE/g for Phoradendron bollanum and Viscum album subs. austriacum, respectively, while aqueous extracts showed a total phenol content of 65 ± 6.9 and 90 ± 1.19 mg GAE/g Phoradendron bollanum and Viscum album subs. austriacum, respectively. HPLC-MS identified largely hydroxycinnamic acids and methoxycinnamic acids. Clavibacter michiganenses was successfully inhibited by aqueous extract of both mistletoes

Reflexiones sobre la educación en diseño en contextos de emergencia

El libro que tiene en sus manos representa el esfuerzo y compromiso que la planta académica de la División de Ciencias y Artes para el Diseño ha asumido durante la pandemia COVID-19, pasar de un aprendizaje tradicional a un aprendizaje digital, para continuar cumpliendo con el compromiso de nuestra institución: formar ciudadanos y profesionistas de alto nivel. Este libro respeta los cinco ejes temáticos propuestos por el comité organizador. 1. Transición de la enseñanza-aprendizaje mediada por tecnologías digitales. 2. Experiencias significativas para los actores (docentes u alumnos). 3. Propuesta pedagógica innovadora. 4. Reflexión sobre la apropiación de las tecnologías digitales y recursos. 5. Diseño de futuros para una educación en diseño. Cada uno de los artículos que integran esta obra está asociado a alguno de estos ejes. En conjunto representan la base de una gran oportunidad que tiene nuestra División para reinventarse y diversificar las experiencias de aprendizaje además de la modalidad presencial. A esta reflexión colectiva también se han sumado las ideas de profesoras y profesores de otras instituciones, con lo cual la experiencia se ha enriquecido aún más al identificar obstáculos y retos compartidos. Hemos descubierto el potencial de la educación digital y dependerá de nosotros el diseñar las estrategias para aprender a convivir también con la educación presencial. Debemos reconocer que las y los profesores no estaban capacitados para un aprendizaje digital, situación no exclusiva de nuestra casa de estudios, en la mayoría de instituciones del sistema de educación superior tampoco estaban preparados. Además de resaltar la falta de políticas de inclusión para favorecer un aprendizaje digital. Estas dos ideas se vuelven elementos centrales para que las universidades asuman un mayor compromiso al respecto.Coordinadoras e [introducción]: Juana Cecilia Ángeles Cañedo y Alma Elisa Delgado Coellar; [Presentación] 2o. Coloquio de Educación en Diseño / Marco Vinicio Ferruzca Navarro; coordinación editorial: Alma Elisa Delgado Coellar y Martha Ivonne Murillo Islas; diseño de interiores, de portada y formación de interiores: Martha Ivonne Murillo Islas; corrección de estilo: Agustina Larrañaga