Expressão de genes relacionados à tolerância à altas temperaturas durante a germinação em sementes de milho

Abstract

In hot regions it is important to use cultivars that are tolerant to high temperatures, especially in the stages of germination and seedling emergence. Thus, the genes identification related to heat tolerance is fundamental to the development of high quality seeds tolerant to this stress condition. The objective of the research was to evaluate maize lineages and the genes expression involved to tolerance to high temperatures during germination by physiological tests, as well as proteomics and transcriptomics analysis. Seeds of six maize lineages with different levels of tolerance to high temperatures were used, three being classified as tolerant and three had low tolerance to high temperatures for germination. In proteomic analysis evaluated the expression of resistant-protein to heat, and of the enzymes catalase, esterase, superoxide dismutase and α-amylase. The genes expression AOX1, AOX2, ZmAN-13, ZmDBP2, late embryogenesis abundant protein and late embryogenesis abundant protein D-34 was studied. It can be concluded that lineages 54 and 91 are more tolerant to high temperature condition; occurs increased enzyme expression α-amylase in corn seeds subjected to controlled damage to the lineages 30 and 91; with controlled deterioration the highest expression of genes does not correlate positively with the tolerant materials; association of lower expression of genes involved in heat-resistant protein systems with lineage 44, this being more susceptible to high temperatures and occurs increased gene expression Lea D34, ZmAN13 and AOX 1 in lineage 64, when the seeds were subjected to controlled deterioration.