Assessing the Ability of Vaginal Orgasticity on the Basis of the Woman's Gait

Background - Despite the recognition that feedstock composition influences biomass conversion efficiency, limited information exists as to how bioenergy crops with reduced recalcitrance can improve the economics and sustainability of cellulosic fuel conversion platforms. We have compared the bioenergy potential—estimated as total glucose productivity per hectare (TGP)—of maize cultivars contrasting for cell wall digestibility across processing conditions of increasing thermochemical severity. In addition, exploratory environmental impact and economic modeling were used to assess whether the development of bioenergy feedstocks with improved cell wall digestibility can enhance the environmental performance and reduce the costs of biomass pretreatment and enzymatic conversion.<br/>Results - Systematic genetic gains in cell wall degradability can lead to significant advances in the productivity (TGP) of cellulosic fuel biorefineries under low severity processing; only if gains in digestibility are not accompanied by substantial yield penalties. For a hypothetical maize genotype combining the best characteristics available in the evaluated cultivar panel, TGP under mild processing conditions (~3.7 t ha−1) matched the highest realizable yields possible at the highest processing severity. Under this scenario, both, the environmental impacts and processing costs for the pretreatment and enzymatic saccharification of maize stover were reduced by 15 %, given lower chemical and heat consumption.<br/>Conclusions - Genetic improvements in cell wall composition leading to superior cell wall digestibility can be advantageous for cellulosic fuel production, especially if “less severe” processing regimes are favored for further development. Exploratory results indicate potential cost and environmental impact reductions for the pretreatment and enzymatic saccharification of maize feedstocks exhibiting higher cell wall degradability. Conceptually, these results demonstrate that the advance of bioenergy cultivars with improved biomass degradability can enhance the performance of currently available biomass-to-ethanol conversion systems.<br/

Cell Wall Diversity in Forage Maize : Genetic Complexity and Bioenergy Potential

Genetic studies are ideal platforms for assessing the extent of genetic diversity, inferring the genetic architecture, and evaluating complex trait interrelations for cell wall compositional and bioconversion traits relevant to bioenergy applications. Through the characterization of a forage maize doubled haploid (DH) population, we indicate the substantial degree of highly heritable (h2 > ~65 %) diversity in cell wall composition and bioconversion potential available within this important agronomic species. In addition to variation in lignin content, extensive genotypic diversity was found for the concentration and composition of hemicelluloses, the latter found to exert an influence on the recalcitrance of maize cell walls. Our results also demonstrate that forage maize harbors considerable variation for the release of cell wall glucose following pretreatment and enzymatic saccharification. In fact, the extent of variability observed for bioconversion efficiency (nearly 30 % between population extremes) greatly exceeded ranges reported in previous studies. In our population, a total of 52 quantitative trait loci (QTL) were detected for biomass compositional and bioconversion characters across 8 chromosomes. Noteworthy, from eight QTL related to bioconversion properties, five were previously unidentified and warrant further investigation. Ultimately, our results substantiate forage maize germplasm as a valid genetic resource for advancing cell wall degradability traits in bioenergy maize-breeding programs. However, since useful variation for cell wall traits is defined by QTL with “minor” effects (R2 = ~10 %), cultivar development for bio-based applications will rely on advanced marker-assisted selection procedures centered on detecting and increasing the frequency of favorable QTL alleles in elite flint and dent germplasm