Differential expression of hormone related genes between extreme segregants of a Saccharum interspecific F2 population

Sugarcane is a highly productive, first generation biofuel feedstock, known for its remarkable efficiency in accumulating biomass. Hormones are important regulators for many biological processes in plants, especially in plant development and plant growth, which are crucial for plant biomass traits. To understand how hormones regulatory mechanisms contribute to sugarcane lignocellulose yield, we studied the transgressive segregation on biomass yield in the F2 population derived from a cross between Saccharum officinarum ‘LA Purple’ and Saccharum robustum ‘MOL5829’. Gene expression profiling was used to detect genes involved in three important hormone-related pathways, auxin, ethylene and gibberellin, to find out how they are differently regulated between the extreme segregants of high and low biomass yield groups. We identified seventeen differentially expressed genes in auxin, one in ethylene and one in gibberellin related signaling and biosynthesis pathways, which could potentially regulate biomass yield. Differentially expressed genes, PIF3 and EIL5, involved in gibberellin and ethylene pathway could play an important role in biomass accumulation. These plant hormone-related genes could serve as candidate genes in genetic modification and breeding programs to develop high yielding energy cane.