THE INFLUENCE OF VEGETAL EXTRACTS AND NANOSTRUCTURED MIXTURES ON GRAPEVINE POLLEN GRAINS

Pesticides, plant bio-stimulants and chemical fertilizers used in intensified viticulture affects negatively the viability of the plants pollen causing relevant economic losses to viticulturists. Given these conditions, we aimed to identify the environmentally friendly phytosanitary treatments which does not negatively affect the evolution of pollen grains. The experiment took place in the greenhouse on 120 grapevine plants from the genotypes Feteasca alba 97 St., Feteasca regala 72 St., Feteasca neagra 6 St., Cabernet Sauvignon 131 St., 30 plants/genotype. These have been treated to combat the Plasmopara viticola and Uncinula necator pathogens with pesticides, biological products, plant extract and nanostructured mixture. The studied genotypes reacted differently regarding the evolution of the viability of pollen grains, the average pollen grains size and the total number of pollen grains. The best results have been registered at F. regala 72 St. (the viability was significantly improved at plants treated with plant extract and those with nanostructured mixture and the highest number of pollen grains was recorded at the plants treated with nanostructured mixture).

VqMYB154 promotes polygene expression and enhances resistance to pathogens in Chinese wild grapevine

Resveratrol plays a crucial phytoalexin role in the grapevine and is beneficial to human health. However, the molecular mechanism of resveratrol accumulation in the enhancement of disease resistance is unclear. Here, we report that the transcription factor VqMYB154 from Vitis quinquangularis accession Danfeng-2 is strongly expressed under artificial inoculation with Uncinula necator and regulates resveratrol accumulation. Unlike its homolog, VqMYB154 has a pathogen-induced promoter and responds to stimulation by U. necator, Pseudomonas syringae, and other treatments. Yeast one-hybrid and GUS activity assays confirmed that VqMYB154 can activate the stilbene synthase genes VqSTS9, VqSTS32, and VqSTS42 by directly binding to their promoters. Overexpression of VqMYB154 in grape leaves resulted in activation of the stilbene pathway, upregulation of STS genes, and accumulation of stilbenoids. In addition, heterologous overexpression of VqMYB154 in Arabidopsis activated resistance-related genes and resulted in greater programmed cell death and accumulation of reactive oxygen species, which led to resistance against P. syringae. These results suggest that the transcription factor VqMYB154 from V. quinquangularis accession Danfeng-2 participates in the regulatory mechanism that improves the biosynthesis and accumulation of stilbenes and enhances resistance to disease in grapevine.

Adaptación de variedades de vid resistentes HPDs y cruces interespecíficos en condiciones tropicales como estrategia de paz en Colombia

En Colombia, la vid se puede considerar como un cultivo promisorio en la era del postconflicto. En esta investigación se evaluó la adaptación de más de cincuenta variedades de vid resistentes a las enfermedades, híbridos productores directos (HPDs) y cruces interespecíficos bajo condiciones tropicales, con el enfoque de encontrar variedades con resistencia para soportar los ataques de Plasmopara viticola, Guignardia bidwelii, Phomopsis viticola, Botrytis cinerea, Uncinula necator, entre otras; así como sus cualidades productivas y de calidad. Otra meta es reducir el número de aplicaciones de agroquimicos por periodo productivo y así lograr que la vid sea un cultivo más amigable con el medio ambiente y económicamente más rentable. Nuestra investigación se ha desarrollado en áreas del valle interandino en el centro de Colombia (departamento del Tolima) en el bosque seco tropical. Esta investigación tiene como propósito, constituirse en una herramienta de implementación de cultivo de la vid, viable económica, social y ambientalmente, como medio de subsistencia a familias campesinas, desplazados y desmovilizados en la era del postconflicto colombiano. A su vez, representa una alternativa de reemplazo a los cultivos ilícitos como la coca y la marihuana, que han prosperado en zonas afectadas por la guerra en Colombia.