Seeded-Yet-Sterile Biomass Feedstocks: Kinggrass & Pearl Millet-Napiergrass.

Kinggrass (Pennisetum purpureum Schumach.  x  P. glaucum [L.] R. Br.) and Pearl Millet-Napiergrass (PMN; P. glaucum  x  P. purpureum) are unique among energy grasses as 'Seeded-yet-Sterile' feedstocks, derived from fertile parents capable of producing significant quantities of hybrid seed while being sterile in subsequent biomass production fields.  Kinggrass and PMN therefore offer seed companies enhanced product control, growers inexpensive crop establishment costs (vs. vegetative propagation), feedstock customers high yields, and governments ecologically oriented systems with reduced risks of crop invasiveness.  As perennial grasses adapted to marginal lands, Kinggrass & PMN further enhance carbon-sequestration potential in sustainable systems without competing for productive land resources currently utilized for food crops.  Development of PMN has been limited due largely to its lack of persistence.  Kinggrass has higher biomass and greater overwintering potential than PMN but has not been pursued as a seeded product due to the lack of an efficient sterility system to facilitate use of P. purpureum as a maternal parent.  The objectives of this research were to: 1) investigate the utility of improved parents towards producing longer-lived PMN hybrids and seeded Kinggrass hybrids, and 2) develop molecular markers capable of confirming Kinggrass and PMN hybrids.  Results to date will be presented and discussed.