A unique feature of biomass sorghums is delayed maturity via
photoperiod-sensitivity (PS).Sorghum is a quantitative short-day
plant, and photoperiod-sensitive(PS) genotypes delay flowering
until aminimum day length is reached.The specific day lengths
vary, but their control is highly heritable.Photoperiod-insensitive
(PI) genotypes do not require a minimum day length to flower and
instead flower with in a characteristic timeframe regardless of latitude or planting date.Under long days as occurs in higher latitudes,
PS sorghums remain vegetative until late in the growing season,
many never flower.Photoperiod insensitive sorghums flower and
mature earlier.This PS delay permits vegetative structures to continue accumulating biomass for increased yields after biomass growth has ceased in earlier maturing materials (Olson etal.,
2012). PS sorghums generally produce higher biomass yields than
PI sorghums,particularly when water is limiting and the growing
season is long(McCollum etal.,2005).