Variation among Half‐Sib Families and Heritability for Biomass Yield and Other Traits in Lowland Switchgrass (Panicum virgatum L.)

Abstract

Switchgrass (Panicum virgatum L.) is a main herbaceous species projected for use as feedstock in biofuel production. Understanding the nature of genetic variation for biomass yield and other important traits in switchgrass would aid cultivar development. The aim of this study was to estimate the genetic component of variation and narrow‐sense heritability for biomass yield and several morphological and phenological traits in lowland switchgrass. Thirty‐seven half‐sib families were evaluated during 2007–2009 at two south central Oklahoma locations, Ardmore and Burneyville. Half‐sib families were different for biomass yields and other traits, suggesting the presence of additive gene action in controlling these traits. Family × location effects were observed for biomass yield and days to spring regrowth. Stem thickness, plant spread, and spring regrowth showed family × year interaction effects. Days to flowering showed a significant family × location × year interaction. Narrow‐sense heritability for biomass yield was 0.13 based on half‐sib family variation and 0.29 based on parent–progeny regression, suggesting a complex genetics of biomass yield. Stem thickness also had low (≤0.27) and plant height and tillering ability had low to moderate (0.26–0.48) heritability. Heritabilities were moderate (0.47–0.70) for heading, flowering, and plant spread and relatively high (≥0.82) for spring regrowth. The biomass yield was positively correlated with tillering ability, plant height, and stem thickness. Rigorous family evaluation procedure and use of tillering ability as an indirect measure to improve biomass yield could enhanced gain from selection.

Bayesian analysis of quantitative traits in popcorn (Zea maysL.) through four cycles of recurrent selection

“…According to the BIC, there was a very strong evidence against the reduced models in which the family effects are assumed to be zero. This result confirmed a significant amount of genetic variation among full-sib families for the traits studied, indicating a significant contribution of additive genes in the expression of these traits (Bhandari et al, 2010). This result is also in accordance with other studies in which the family effect was significant used in this study.…”

QTL Mapping for Reproductive Maturity in Lowland Switchgrass Populations

“…In upland tetraploid switchgrass, among-and-within-family selection proved moderate heritability (0.41) for plant height, with greater values for selection of increased height, while heritability for tiller count was generally low (0.06), and flowering date was estimated to have high heritability (0.75) overall in both selection direction (Price et al 2014). In lowland switchgrass, according to the research of Bhandari et al (2010), half-sib families were different for biomass yields and other traits, suggesting that the presence of additive gene effect in controlling these traits. Heritabilities were moderate (0.40-0.70) for heading, flowering, and plant spread.…”

“…Talbert et al (1983) reported high narrow-sense heritabilities (0.91 or above) for switchgrass maturity based on a lowland population of 33 half-sib families. Using 37 lowland half-sib families of one lowland population, Bhandari et al (2010) reported moderate to high (0.58-0.74) narrow sense heritabilities for heading and flowering time. Bhandari et al (2011) observed heritability estimates for heading date were larger based on full-sib families than on half-sib families, suggesting dominant gene effect or epistasis likely played an important role.…”

Cell Wall Composition and Underlying QTL in an F1 Pseudo-Testcross Population of Switchgrass

“…These heritability estimates are similar to those made for biomass yield (0.29-0.65) and related traits (plant height <0.27, tillering 0.28-0.48, etc.) in other populations of switchgrass [38][39][40].…”