Identification of Species, Genes, and Traits Appropriate for Low-Input Biomass Production in Western North America.

Identification of species, genes, and trait appropriate for low-input biomass production in western North America

Steve Larson, Kevin Jensen, Tom Jones, and Joe Robins

Specialized perennial grasses are needed for efficient and sustainable feedstock production in the high-altitude, cold-growing regions of the western North America. Basin wildrye (Leymus cinereus) and creeping wildrye (Leymus triticoides) are cool-season perennial Triticeae grasses native to western North America. Basin wildrye is an unusually tall grass, reaching over 2 m high in some cases, and is considered one the largest native grasses in this region. Creeping wildrye is strongly rhizomatous grass, with more tiller branches. Interspecific hybrids of basin wildrye and creeping wildyre display a heterotic combination of traits with high seasonal biomass accumulation potential. High-density, molecular genetic maps for two full-sib TTC1 and TTC2 families derived from two L. triticoides x L. cinereus F1 hybrids backcrossed to one L. triticoides tester (T-tester), constructed using a combination of AFLP markers and heterologous gene markers, were previously used to identify QTLs controlling growth habit (rhizome spreading), plant height, and flowering variation (including some progeny that never flowered). In this report, over 400 new Leymus EST markers will be integrated in one consensus map for both TTC1 and TTC2 families. Integrated consensus maps will be used to identify QTL controlling seasonal biomass accumulation using first-year, 2008 harvest data from new clonally replicated, multi-year, TTC1 and TTC2 field evaluations established near Logan, Utah and Tetonia, Idaho in the spring of 2007. First-year biomass accumulation of basin wildrye, creeping wildrye, and Leymus wildrye hybrids will also be compared to tall wheatgrass (Thinopyrum intermedium), intermediate wheatgrass (Thinopyrum ponticum), giant wildrye (Leymus racemosus), western wheatgrass (Pascopyrum smithii), switchgrass (Panicum virgatum), reed canary grass (Phalaris arundinceae), meadow brome (Bromus riparius), robust needlegrass (Achnatherum robustum) and tall fescue (Festuca arundinceae). These experiments aim to identify species, genes, and novel trait combinations traits required for low-input feedstock and bioenergy production in unique cold-growing environments of western North America.