Caracterização de genótipos mutantes de arroz para tolerância à salinidade e as baixas temperaturas

Abstract

The state of Rio Grande do Sul is the main rice producing state in Brazil. Climatic conditions such as low temperatures cause production to suffer considerable losses in rice production. Another limiting environmental factor for productivity is salinity, as it affects a large part of the irrigated rice crops in Rio Grande do Sul, which are irrigated with water from Lagoa dos Patos, which, according to precipitation, ends up receiving water from the Ocean, causing the salt content in the water to increase. This increase in water salinity causes the plant to be impaired in its development, which causes a series of molecular, biochemical, physiological, and morphological changes. Due to this condition thousands of hectares are affected in the world and in Brazil. Salinity tolerance is a quantitative trait, and plants show different types of responses, depending on their stage of development, it becomes a very complex trait, being a great challenge for researchers who want to identify genes that are responsible for this mechanism. Low temperatures negatively affect rice growth and yield. Understanding the physiological changes caused by cold stress, and seeking to understand its genetic causes, will help in the discovery of cold-tolerant rice. The search for tolerant genotypes is essential to alleviate the problem and knowledge of the genetic basis of tolerance enhances the improvement process. This work aimed to characterize salinity-tolerant rice mutants (M5) in the reproductive and vegetative stages for cold tolerance.