Avaliação de genótipos de arroz para tolerância à seca e o papel da regulação transcricional de genes responsivos à auxina

Abstract

Drought is one of the most important abiotic factor that affect the yield of many cultures. Even in tropical regions with regular precipitation, in the some stages of life cicle the culture´s face drought stress, and with climats change´s this situation are been more severe. For that the main objective os this work is to evaluate drought tolerance and gene transcricional of five genes regulated by auxin envolved in rice roots development. For morphologycal characterization the drought stress condiction was obteined adding 10% of Polyethylene glycol 6000, for a pressure of -1,44MPa. The sequences for gene expression were obtained in RAP-DB and NCBI, the mRNA was extrated using the Pure LinkTM Plant RNA Reagent (InvitrogenTM). Stressed seedlings register reduction in shoots length, shoot dry matter, and root number and an increase of root development, root dry matter, ratio of root and shoot dry matter. Genotypes showed varied responses as to the association of the characteristics of the radicular system in stress response. It was not possible to associate the morphological characteristics with the transcriptional profile of a specific gene, although differences between genotypes were observed.