<p>Plant biomass is an abundant source of renewable energy, but the efficiency of its conversion into liquid fuels is low. One reason for this inefficiency is the recalcitrance of biomass to extraction and saccharification of cell wall polysaccharides. This recalcitrance is due to the complex and rigid structure of the plant cell wall. A better understanding of the genes effecting cell wall composition in bioenergy crops could improve feedstock quality and increase conversion efficiency. To identify genetic loci associated with biomass quality traits, we utilized genome-wide association studies (GWAS) in an 840-line <i>Sorghum</i> diversity panel. We identified several QTL from these GWAS including some for lignin composition and saccharification. Linkage disequilibrium (LD) analysis suggested that multiple polymorphisms are driving the association of SNPs within these QTL. Sequencing and further analysis led to the identification of a SNP within the coding region of a gene encoding phenylalanine ammonia-lyase (PAL) that creates a premature stop codon and co-segregates with an increase in the ratio of syringyl (S) to guaiacyl (G) lignin. A comparison of net PAL activity between lines with and without the mutation revealed that this mutation results in decreased PAL activity. </p>

Sweet sorghum (Sorghum bicolor) has potential as a bioenergy feedstock due to its high yield potential and the production of simple sugars for fermentation. Sweet sorghum cultivars are typically tall, high biomass types with juicy stalks and high sugar concentration. These sorghums can be harvested, milled, and fermented to ethanol using technology similar to that used to process sugarcane. Sweet sorghum has advantages in that it can be planted by seed with traditional planters, is an annual plant that quickly produces a crop and fits well in crop rotations, and it is a very water-use efficient crop. Processing sweet sorghum is capital intensive, but it could fit into areas where sugarcane is already produced. Sweet sorghum could be timed to harvest and supply the sugar mill during the off season when sugarcane is not being processed, be fit into crop rotations, or used in water limiting environments. In these ways, sweet sorghum could be used to produce ethanol in the Southern U.S and other tropical and subtropical environments. Traditionally, sweet sorghum has been grown as a pureline cultivar. However, these cultivars produce low quantities of seed and are often too tall for efficient mechanical harvest. Sweet sorghum hybrids that use grain-type seed parents with high sugar concentrations are one way to overcome limitation to seed supply and to capture the benefits of heterosis. There are four objectives of this research. First to evaluate the importance of genotype, environment, and genotype-by-environment interaction effects on the sweet sorghum yield and composition. The second objective is to determine the presence and magnitude of heterosis effects for traits related to sugar production in sweet sorghum. Next: to study the ability of sweet sorghum hybrids and cultivars to produce a ratoon crop and determine the contribution of ratoon crops to total sugar yield. The final objective is to evaluate variation in composition of sweet sorghum juice and biomass. Sweet sorghum hybrids, grain-type sweet seed parents, and traditional cultivars that served as male parents were evaluated in multi-environment trials in Weslaco, College Station, and Halfway, Texas in 2007 and 2008. Both genotype and environment influenced performance, but environment had a greater effect than genotype on the composition of sweet sorghum juice and biomass yield. In comparing performance, elite hybrids produced fresh biomass and sugar yields similar to the traditional cultivars while overcoming the seed production limitations. High parent heterosis was expressed among the experimental hybrids for biomass yield, sugar yield and sugar concentration. Additional selection for combining ability would further enhance yields and heterosis in the same hybrid. Little variation was observed among hybrids for juice and biomass composition suggesting that breeding efforts should focus on yield before altering plant composition.

Research goal. We seek to validate optimal composition of straw biomass fuel and energy efficiency of straw utilization for energy needs, to assess straw biomass fuel preparation technology in respect to energy efficiency, and to determine emissions that are generated during straw combustion. Research objectives. The following objectives were planned to reach the goal of the research: 1) Process analysis of preparation of biomass fuel (pellets and briquettes) for burning, 2) Validation of mixture of lime additive (CaO) into straw biomass fuel, 3) Property analysis of prepared biomass fuel, 4) Measurement and assessment of emissions generated while burning straw biomass fuel, 5) Assessment of energy consumption by straw pellet production equipment. / Tyrimų tikslas. Pagrįsti šiaudų biokuro optimalios sudėties paruošimo ir panaudojimo energinėms reikmėms efektyvumą, atlikti šiaudų biokuro paruošimo technologijos energinį vertinimą ir nustatyti deginimo metu išskiriamas emisijas. Tyrimų uždaviniai. Tyrimų tikslui pasiekti numatyta: 1) Atlikti šiaudų biokuro (briketų ir granulių) paruošimo deginimui technologinę analizę; 2) Pagristi kalkių priedo (CaO) įmaišymo į šiaudų biokuro sudetį tikslingumą; 3) Ištirti pagaminto šiaudų biokuro savybes; 4) Nustatyti ir įvertinti šiaudų biokuro deginimo metu išskiriamas emisijas; 5) Įvertinti šiaudų granulių gamybos technologinės įrangos energijos sanaudas.

When microalgae are exposed to changing environmental conditions, e.g., light-dark cycles or oscillations in nutrient availability (CO2, nitrogen, phosphate or silicate) they respond with metabolic changes in the carbon allocation pattern. Short time regulations in the time range of few seconds to minutes can be mirrored best by mass spectroscopy based metabolomics. However, these snap shots do not reflect the alterations in the carbon flow to the cellular macromolecules like protein, carbohydrate or lipid. In this review it is shown how the combination of FTIR spectroscopy and Chla-in-vivo-fluorescence based electron transport rates can reveal changes in the metabolic flux rates of carbon during a shift of the environmental conditions. The review will demonstrate in which time range FTIR spectroscopy can deliver significant information and how FTIR spectroscopy data can synergistically support metabolome analysis by mass-spectroscopy.