Project description:Summary The expression profile of internodes from high brix plant was compared to internodes from low brix plants. Mature (In9), intermediate (In5) and immature internodes (In1) were collected from two different Progenies and immediately frozen in liquid nitrogen. Total RNA was extracted using Trizol. Progeny 1 was derived from two intra-specific polycrosses, one among Saccharum officinarum genotypes and the other combining Saccharum spontaneum genotypes. For each generation, 500 individuals were sampled for brix content and gene expression. The extreme segregants were selected for further analysis. The F3 hybrid individuals selected for molecular studies were planted in a field in single rows of 5 m using standard sugarcane cultivation practices. Brix readings and tissue samples were collected very early in the season, and in March of the following year, when plants were 10 months old. The soluble solids (brix) content of mature internodes of each sugarcane stalk was measured with a portable refractometer (N1 model, ATAGO, Japan). Individuals or pools of eight individuals had their tissues collected and RNA extracted. Progeny 2 was derived from a cross between two commercial varieties (SP80-180 x SP80-4966). Five hundred sugarcane F1 plants were field-grown. The stem sugar content from the different plants showed a normal distribution, and seven plants with extreme brix values were collected. Keywords: Expression profiling by array
