Genetic Variability and Trait Relationships in Switchgrass

Abstract

chromosome numbers ranging from 2n ϭ 2x ϭ 18 to 2n ϭ 12x ϭ 108 (Nielson, 1944;McMillan and Weiler, Greater knowledge of the magnitude of genetic variability for bio- Henry and Taylor, 1989). Switchgrass is classified mass yield and yield components in switchgrass, Panicum virgatum L., and relationships among the biomass yield component traits would into upland and lowland ecotypes based on morphology facilitate the breeding improvement of the species. Accordingly, we and habitat preference (Porter, 1966). All confirmed conducted two replicated experiments to assess genetic variation for lowland ecotypes have been tetraploids and most upland biomass yield and yield components and quantify relationships among ecotypes are octoploids (Hopkins et al., 1996). those traits in different switchgrass populations. In Exp. 1, 228 half-sib Information on the variability and associations of biofamilies from SU C 3 and 261 from NU C 3 populations were evaluated at mass yield and yield components in switchgrass is lim-Perkins, OK, while 278 half-sib families from the SL C 0 population ited. Talbert et al. (1983) reported narrow-sense heriwere evaluated at Stillwater, OK. Exp. 2 comprised 11 lowland switchtability estimates of 0.25 and 0.59 based on individual grass populations tested at Chickasha and Perkins, OK, in 1998. Sub-half-sib progeny and half-sib progeny means, respecstantial differences (P Ͻ 0.01) in biomass yield per plant existed among half-sib families within the respective SU C 3 , NU C 3 , and SL C 0 popula-

Estimation of genetic variability and heritability for biofuel feedstock yield in several populations of switchgrass

“…Boe & Lee (2007) reported h 2 n estimates of 0.60 and 0.62 from variance component methods for biomass yield for the upland ecotype varieties of switchgrass Sunburst and Summer, respectively. Das et al (2004) reported significant variability for biomass yield and several yield components in switchgrass but did not report heritability estimates of these traits.…”

Developmental Morphology and Biomass Yield of Upland and Lowland Switchgrass Ecotypes Grown in Iowa

“…These ecotypes possess large genotypic, phenotypic, and physiological differences between them [13][14][15][16][17][18]. Lowland cultivars are generally tall, thick-stemmed, later flowering, adapted to wetter conditions, and have higher biomass yield potential, compared to the upland ecotypes [19][20][21].…”

Internode structure and cell wall composition in maturing tillers of switchgrass (Panicum virgatum. L)

“…Several studies have documented the variability that exists within available switchgrass populations with respect to important agronomic traits, such as tillering, digestibility and biomass production (Redfearn et al, 1997b;Das et al, 2004;Smart et al, 2004). Although, these studies have documented the potential for germplasm improvement in this important forage and biofuel crop there is still limited information on the anatomical, biochemical and physiological processes affecting these attributes.…”