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Shikimic acid is the critical precursor to manufacture the antiviral drug Oseltamivir phosphate, also known as Tamiflu. Current sources of shikimic acid feedstock have been strained during pandemic influenza outbreaks. This article proposes an alternative process to produce shikimic acid feedstock through the bioenhancement of graminoid crops using glyphosate. To demonstrate, a Gulf cultivar of Italian annual ryegrass (Lolium multiflorum Lam.) was grown in controlled greenhouse conditions and Yamhill winter wheat (Triticum aestivum L.) was grown in a field trial. Plants were treated with a range of glyphosate doses and harvested between 48 and 298 h following application. Samples were dried, extracted, and analyzed by high performance liquid chromatography. Shikimic acid levels increased up to four-fold in glyphosate-treated Gulf annual ryegrass, a plant with high native shikimic acid. Concentrations of shikimic acid in Yamhill winter wheat, a plant low in native shikimic acid, increased from below method detection limits (<19 mg kg-1) in the control groups to >2000 mg kg-1 in treatment groups harvested after 169 h post application. Estimated biomass accumulation of shikimic acid were projected using concentrations observed in these trials for annual ryegrass, alfalfa (Medicago sativa L.), and winter wheat based on published biomass yields resulted in 21.1 to 299 kg of potential shikimic acid production per hectare, which meet or exceed current feedstocks. This study provides evidence that glyphosate can be used to bioenhance graminoid forage crops to produce elevated shikimic acid levels throughout the entire plant biomass, resulting in a substantially greater yield of shikimic acid than current botanical sources on a per-hectare basis. [ABSTRACT FROM AUTHOR]

Reed canarygrass (Phalaris arundinacea L.) is a perennial C3 grass with a circumglobal distribution in the Northern Hemisphere and adaptation to a wide range of environmental conditions. This species is currently under development as a bioenergy feedstock in North America and Europe. Thus, the objectives of this study were to (i) quantify genetic variation for biomass quality traits of reed canarygrass cultivars and accessions, (ii) determine the relationships for biomass yield with reed canarygrass quality traits, and (iii) identify favorable and attainable breeding objectives for biomass yield and quality traits of reed canarygrass. Eighty cultivars or accessions were grown at five field locations and evaluated for 26 biomass quality traits in 2006 through 2008. Ignoring biomass quality traits in favor of the singular breeding objective of high biomass yield would be likely to result in a few favorable correlated responses including low N, low ash, low Cl, low Fe, and high enzymatic xylan conversion efficiency. These changes would not be sufficiently large to transform reed canarygrass into a more favorable bioenergy feedstock within a few generations of breeding. To do so will require a more focused effort with a relatively small number of traits, for example, high biomass yield, low ash, and high gross calorific value (GCV) for a thermochemical conversion platform or high biomass yield, low lignin, and high glucan and xylan conversion efficiencies for a fermentation platform. [ABSTRACT FROM AUTHOR]

Miscanthus is a promising feedstock for secondgeneration bioethanol production. This perennial crop produces its biomass in two phases: a yieldbuilding phase, where the biomass production increases gradually, and a plateau phase, where it is maintained. However, to target the breeding of Miscanthus for second-generation bioethanol production, the early selection of interesting traits is critical. We therefore investigated the interannual correlations within and among the traits related to biomass production and composition. We studied 21 clones belonging to M. × giganteus J. M. Greef & Deuter ex Hodk. & Renvoize, M. sacchariflorus (Maxim.) Benth. & Hook. f. ex Franch., and M. sinensis Andersson species cultivated on plots from the second to the sixth year at two harvest dates. The biomass production, canopy height, plant stem number, and aboveground plant volume index were better predicted from the third year than from the second year (minimum correlation coefficients of 0.76 and 0.67 respectively). The stem diameter was well predicted from the second year (correlations above 0.93). The canopy height and the aboveground plant volume index determined in the second and third year were the best predictors of the biomass produced in the second, third, and fourth year (minimum correlations of 0.77 against 0.52 for flowering date or 0.64 for stem diameter). For older crops, the canopy height measured in the second and third year was the best predictor of the biomass production (correlations above 0.70). The interannual correlations were lower for the biomass composition-related traits than for the production-related traits and fluctuated over time. These results showed that early prediction of interesting traits is feasible to breed varieties tailored for biofuel production. [ABSTRACT FROM AUTHOR]

Switchgrass (Panicum virgatum L.) is a candidate for cellulosic bioenergy feedstock development in many parts of North America. Because production costs are generally considered too high for economic and sustainable production of switchgrass biomass, breeding for increased biomass yield is a viable and desirable research objective. The objective of this study was to estimate heterosis and reciprocal-cross effects in three types of switchgrass crosses: upland × upland (U×U), lowland × lowland (L×L), and upland × lowland (L×U) hybrids. A total of 62 hybrids and two parental populations were evaluated for 2 yr at two Wisconsin locations. Mid-parent heterosis for biomass yield was observed in only four L×L hybrids and no L×U hybrids, suggesting that it is not a universal phenomenon between upland and lowland ecotypes. Reciprocal effects were more important than heterosis effects, as most hybrids were similar in performance to their maternal parent population. Flowering time was a strong driver of biomass yield, accounting for 67% of the variation among hybrids in biomass yield and increasing biomass yield by 0.47 Mg ha-1 for each day delay in flowering time. [ABSTRACT FROM AUTHOR]