Transcriptomic Analysis of Extreme Segregants in an Interspecific Saccharum F2 Population

Sugarcane accounts for ~80% of the global sugar production and is a major source of ethanol based biofuels. As a C₄ plant coupled with its perennial nature, sugarcane is one of the most efficient crops in converting solar energy into chemical energy and has high biomass yield. Its impact on biofuel industry is even greater as second generation lignocellulosic biofuel is almost profitable. An interspecific F2 population derived from S. officinarum LA Purple x S. robustum MOL5829 showed transgressive segregation with high yielding clones substantially exceeding the biomass yield of both parents. Yield test of the extreme segregants had been carried out and their cell wall compositions were examined. Transcriptomic sequences from leaf and stalk at different developmental stages were generated from the top five and bottom five extreme segregants. Differentially expressed genes between these two groups were analyzed, including annotated genes in sucrose, starch, lignin and cellulose biosynthesis pathway. Transgressive segregation in autopolyploid sugarcane F2 populations has the potential to accelerate energy cane breeding program.