Location: Forage and Range Research
Title: Genes and QTLs controlling biomass yield and composition traits in perennial wildrye Authors
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: December 28, 2013
Publication Date: January 16, 2014
Citation: Wu, X., Yun, L., Larson, S.R., Jensen, K.B., Pearson, C., Robins, J.G. 2014. Genes and QTLs controlling biomass yield and composition traits in perennial wildrye. Meeting Abstract. Technical Abstract: Native perennial grasses provide low-input feedstocks that can be used for livestock or possibly biofuel. Basin wildrye (Leymus cinereus) is consideed one of the largest native grasses in western North America. It has stout stems up to 3 m tall but its high compact crown is susceptible to defoliation. Creeping wildrye (Leymus triticoides) a shorter less productive grass with durable rhizomes, many-fine stems, and higher forage quality. Interspecific creeping x basin wildrye hybrids display a useful combination of traits, with biomass yields equal or greater than basin wildrye. Reciprocal backcross populations derived from interspecific hybrids were used to identify quantitative trait loci (QTLs) controlling plant height, rhizome spreading, flowering, tiller number, seasonal biomass accumulation, cellulosic fiber, lignin, and protein traits using a linkage maps that include 440 Leymus EST markers. Basin wildrye had positive effects for 10 dominant biomass QTLs, creeping wildrye had positive effects for one dominant biomass QTL, and both species showed positive effects for one overdominant biomass QTL. Biomass QTLs associated with plant height and tiller number were aligned to genes controlling dwarfing, and vernalization in wheat and barley, including the syntenous Vrn1 and Vrn2 genes on chromosome 5Ns. Late-season forage quality was associated with genes and QTLs controlling flowering and photoperiod response, whereas QTLs associated with early-season forage quality aligned to lignin biosynthesis genes. Evidence suggests that genetic mechanisms controlling plant height, flowering, and tillering are conserved among temperate grasses and reveals possible pathways for improving biomass production and forage quality.