RESUMO
Polyploidy, defined as the coexistence of three or more complete sets of chromosomes in an organism's cells, is considered as a pivotal moving force in the evolutionary history of vascular plants and has played a major role in the domestication of several crops. In the last decades, improved cultivars of economically important species have been developed artificially by inducing autopolyploidy with chemical agents. Studies on diverse species have shown that the anatomical and physiological changes generated by either natural or artificial polyploidization can increase tolerance to abiotic and biotic stresses as well as disease resistance, which may positively impact on plant growth and net production. The aim of this work is to review the current literature regarding the link between plant ploidy level and tolerance to abiotic and biotic stressors, with an emphasis on the physiological and molecular mechanisms responsible for these effects, as well as their impact on the growth and development of both natural and artificially generated polyploids, during exposure to adverse environmental conditions. We focused on the analysis of those types of stressors in which more progress has been made in the knowledge of the putative morpho-physiological and/or molecular mechanisms involved, revealing both the factors in common, as well as those that need to be addressed in future research.
RESUMO
Medicinal and aromatic plants are biologically and economically valuable species because of their intrinsic value as plants, ability to produce secondary metabolites, possible use in the pharmaceutical and food industries, germplasm availability and applications in traditional medicine. In addition, they hold social and economic importance due to the ancestral knowledge they represent and because they are part of the livelihood of many families. Most of them are collected from the wild and are in serious danger of extinction. Through biotechnological tools it is possible to develop their germplasm and obtain new and improved varieties from wild material, while advocating the alternative of production by cultivation instead of extracting it from nature. The objective of this review is to provide an updated perspective on the traditional uses, conservation status and biotechnological advances in a group of 30 plant species native to the American continent.
Las plantas medicinales y aromaÌticas deben ser valoradas tanto por su valor intriÌnseco como tales, por su capacidad de producir metabolitos secundarios, su posible uso en las industrias farmaceÌutica y alimentaria y por sus aplicaciones en medicina tradicional. AdemaÌs, tienen importancia social y econoÌmica debido al conocimiento ancestral que representan y porque son parte del sustento de muchas familias. La mayoriÌa de estas especies son recolectadas de la naturaleza y estaÌn en grave peligro de extincioÌn. A traveÌs de herramientas biotecnoloÌgicas es posible desarrollar su germoplasma y obtener variedades nuevas y mejoradas a partir de material silvestre; esta estrategia propicia la alternativa de produccioÌn por cultivo en lugar de extraerla de la naturaleza. El objetivo de esta revisioÌn es proporcionar una perspectiva actualizada de los usos tradicionales, el estado de conservacioÌn y los avances biotecnoloÌgicos en un grupo de 30 especies de plantas nativas del continente americano.