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1.
Miscanthus × giganteus (M×g) is the primary species of Miscanthus for bioenergy feedstock production. The current leading biomass cultivar, M×g ‘1993‐1780’, is insufficiently adapted in temperate regions with cold winters such as USDA hardiness zone 5 (average annual minimum temperature of ?28.9 to ?23.3°C) or lower. Three interconnected Miscanthus F1 populations that shared a common parent were planted in a replicated field trial at Urbana, IL (hardiness zone 5b; average annual minimum temperature of ?26.1 to ?23.3°C) in spring 2011. The winter of 2013–2014 was especially cold in Urbana, with a minimum soil temperature at 10 cm of ?6.2°C and a minimum air temperature of ?25.3°C, giving us an opportunity to evaluate hardiness on established year‐3 plants. The parent in common to all three populations, M. sinensis ssp. condensatus ‘Cosmopolitan’, is native to maritime southern Japan, and in Urbana, it is winter‐damaged most years. In contrast, the three other parents, M. sacchariflorus ‘Robustus’ (MapA), M. sinensis ‘Silberturm’ (MapB), and M. sinensis ‘November Sunset’ (MapC), are typically winter hardy in Urbana. Nearly all MapA progeny plants survived and grew vigorously in spring 2014, whereas in MapB and MapC, many progeny plants did not survive the winter, and most of the survivors were severely damaged, with poor vigor. Negative correlations between overwintering ability and spring regrowth date and autumn dormancy date suggested that the genotypes most likely to survive winters were those that emerged early in spring and/or went dormant early in autumn. Using joint‐population analysis, we identified 53 quantitative trait loci (QTLs) for nine adaptation traits, including nine QTLs for overwintering ability and 11 for spring hardiness scores. Many biologically intuitive candidate genes were observed within or near the QTLs detected in this study, suggesting their validity and potential for further study.  相似文献   

2.
To breed improved biomass cultivars of Miscanthus ×giganteus, it will be necessary to select the highest‐yielding and best‐adapted genotypes of its parental species, Miscanthus sinensis and Miscanthus sacchariflorus. We phenotyped a diverse clonally propagated panel of 569 M. sinensis and nine natural diploid M. ×giganteus at one subtropical (Zhuji, China) and five temperate locations (Sapporo, Japan; Leamington, Ontario, Canada; Fort Collins, CO; Urbana, IL; and Chuncheon, Korea) for dry biomass yield and 14 yield‐component traits, in trials grown for 3 years. Notably, dry biomass yield of four Miscanthus accessions exceeded 80 Mg/ha in Zhuji, China, approaching the highest observed for any land plant. Additionally, six M. sinensis in Sapporo, Japan and one in Leamington, Canada also yielded more than the triploid M. ×giganteus ‘1993‐1780’ control, with values exceeding 20 Mg/ha. Diploid M. ×giganteus was the best‐yielding group at the northern sites. Genotype‐by‐environment interactions were modest among the five northern trial sites but large between Zhuji, and the northern sites. M. sinensis accessions typically yielded best at trial sites with latitudes similar to collection sites, although broad adaptation was observed for accessions from southern Japan. Genotypic heritabilities for third year yields ranged from 0.71 to 0.88 within locations. Compressed circumference was the best predictor of yield. These results establish a baseline of data for initiating selection to improve biomass yield of M. sinensis and M. ×giganteus in a diverse set of relevant geographies.  相似文献   

3.
4.
High biomass yields have been documented for Tripidium spp. (Erianthus spp., Saccharum spp.), but targeted breeding for bioenergy applications has been limited. Advanced, interspecific hybrids between Tripidium ravennae and T. arundinaceum were planted in replicated field plots in 2016. Comparative feedstock evaluations examined biomass yields, cytogenetics, plant fertility, and compositional analyses relative to Miscanthus × giganteus. Dry biomass yields varied as a function of year and accession and increased each year ranging from 3.4 to 10.6, 8.6 to 37.3, and 23.7 to 60.6 Mg/ha for Tripidium hybrids compared to 2.3, 16.2 and 27.9 Mg/ha for M. × giganteus in 2016, 2017, and 2018, respectively. Cytology and cytometry confirmed that Tripidium hybrids were tetraploid with 2n = 4x = 40 (2C genome size = 5.06 pg) and intermediate between T. ravennae with 2n = 2x = 20 (2C genome size = 2.55 pg) and T. arundinaceum with 2n = 6x = 60 (2C genome size = 7.61 pg). Plant fertility characteristics varied considerably with some accessions producing no viable seeds or fewer than that observed for M. × giganteus. Accessions varied significantly for flowering culm number and height and dates of peak anthesis ranging from 14 September to 2 October. Variations in yield and compositional analyses contributed to variations in theoretical ethanol yields ranging from 10,181 to 27,546 L/ha for Tripidium accessions compared to 13,095 L/ha for M. × giganteus. Relative feed value (RFV) indices for winter‐harvested Tripidium accessions varied from 52.8 to 60.0 compared to M. × giganteus with 45.4. RFV for summer‐harvested Tripidium accessions varied from 71.6 to 80.5 compared to M. × giganteus with 61.0. These initial findings for Tripidium hybrids, including high biomass yields, cold hardiness, and desirable traits for multiple markets (e.g., forage, bioenergy, bioproducts), are promising and warrant further development of Tripidium as a temperate bioenergy feedstock.  相似文献   

5.
Ravenna grass, Tripidium ravennae (L.) H. Scholz, is known to produce an abundance of biomass, but how plant density affects its biomass potential remains unknown. The objectives were to determine the effects of plant density on biomass yield; plant growth traits; biomass?carbon, nitrogen, and ash concentrations; heating value; nitrogen removal; and sucrose concentration in leaves and culms. The treatments consisted of five plant densities (1,250; 2,500; 5,000; 10,000; and 20,000 plants per hectare) in a randomized complete block design with four blocks. Plots were nonirrigated, unfertilized, and harvested once during the dormant season each year. Data were collected from 2015?2019. Dependent variables that varied with plant population density (p < .05) were biomass yield, number of reproductive culms per plant, reproductive culm diameter, reproductive culm sucrose concentration, and nitrogen removal with biomass. Biomass yield ranged from 5.6 to 16.3 Mg/ha for plant densities of 1,250–20,000 plants per hectare, respectively. Combined over years, nonlinear regression of the data showed the equation for biomass yield to plateau at 16.2 Mg/ha at a plant density of 10,640 plants per hectare. As plant density increased, the number of reproductive culms per plant, culm diameter, and culm sucrose concentration significantly decreased. At 1,250 plants per hectare, the number of reproductive culms per plant, culm diameter, and culm sucrose averaged 70, 10.2 mm, and 63.2 g/kg, respectively. Nitrogen removed with biomass significantly increased as biomass yield increased with plant density. At a density of 10,000 and 20,000 plants per hectare, the amount of nitrogen removed annually in the harvested biomass averaged 88 kg/ha. The data suggest that 10,000 plants per hectare would produce the greatest annual biomass yields; however, research is needed to determine the nutrient requirement for Ravenna grass to sustain biomass production at that density.  相似文献   

6.
Soil organic carbon (SOC) is an important carbon pool susceptible to land‐use change (LUC). There are concerns that converting grasslands into the C4 bioenergy crop Miscanthus (to meet demands for renewable energy) could negatively impact SOC, resulting in reductions of greenhouse gas mitigation benefits gained from using Miscanthus as a fuel. This work addresses these concerns by sampling soils (0–30 cm) from a site 12 years (T12) after conversion from marginal agricultural grassland into Miscanthus x giganteus and four other novel Miscanthus hybrids. Soil samples were analysed for changes in below‐ground biomass, SOC and Miscanthus contribution to SOC (using a 13C natural abundance approach). Findings are compared to ECOSSE soil carbon model results (run for a LUC from grassland to Miscanthus scenario and continued grassland counterfactual), and wider implications are considered in the context of life cycle assessments based on the heating value of the dry matter (DM) feedstock. The mean T12 SOC stock at the site was 8 (±1 standard error) Mg C/ha lower than baseline time zero stocks (T0), with assessment of the five individual hybrids showing that while all had lower SOC stock than at T0 the difference was only significant for a single hybrid. Over the longer term, new Miscanthus C4 carbon replaces pre‐existing C3 carbon, though not at a high enough rate to completely offset losses by the end of year 12. At the end of simulated crop lifetime (15 years), the difference in SOC stocks between the two scenarios was 4 Mg C/ha (5 g CO2‐eq/MJ). Including modelled LUC‐induced SOC loss, along with carbon costs relating to soil nitrous oxide emissions, doubled the greenhouse gas intensity of Miscanthus to give a total global warming potential of 10 g CO2‐eq/MJ (180 kg CO2‐eq/Mg DM).  相似文献   

7.
The 8,000 biogas plants currently in operation in Germany are mainly fed with biomass from annual crops. However, feedstock from perennial crops such as miscanthus is expected to be more environmentally benign. If miscanthus is to be used in greater amounts as a substrate for anaerobic digestion, storage will become a relevant topic, as a continuous supply of biomass throughout the year is necessary. The objective of this study was to identify the miscanthus harvest time that best balances the simultaneous achievement of high silage quality, high digestibility and high methane hectare yields. For this purpose, biomass from four miscanthus genotypes with varying senescence characteristics was harvested on three different dates in autumn 2017. Part of the biomass was ensiled, and the methane yield of both ensiled and non‐ensiled biomass was analysed in a biogas batch test to assess the effect of ensiling on the methane hectare yield and digestion velocity. The ensiled biomass was found to have an up to 7% higher substrate‐specific methane yield and also showed a higher digestion velocity than the non‐ensiled biomass. The silage quality was best when miscanthus was harvested in mid‐October, due to highest lactic acid content (average: 3.0% of DM) and lowest pH (average: 4.39) compared to the harvests in mid‐September and beginning of October. Mass losses during ensiling (as high as 7.6% of fresh matter for the M. sinensis genotype Sin55) were compensated for by a higher substrate‐specific methane yield (up to 353 Nml CH4 (g oDM)?1) in ensiled miscanthus. This resulted in non‐significantly different methane hectare yields for non‐ensiled (average: 4.635 Nm3 CH4/ha) and ensiled miscanthus biomass (4.803 Nm3 CH4/ha). A comparison of the four genotypes suggests that Miscanthus x giganteus is the most suitable genotype for ensiling as it had the best silage quality.  相似文献   

8.
The bioenergy crop Miscanthus × giganteus has a high water demand to quickly increase biomass with rapid canopy closure and effective rainfall interception, traits that are likely to impact on hydrology in land use change. Evapotranspiration (ET, the combination of plant and ground surface transpiration and evaporation) forms an important part of the water balance, and few ET models have been tested with Miscanthus. Therefore, this study uses field measurements to determine the most accurate ET model and to establish the interception of precipitation by the canopy (Ci). Daily ET estimates from 2012 to 2016 using the Hargreaves–Samani, Priestley–Taylor, Granger–Gray, and Penman–Monteith (short grass) models were calculated using data from a weather station situated in a 6 ha Miscanthus crop. Results from these models were compared to data from on‐site eddy covariance (EC) instrumentation to determine accuracy and calculate the crop coefficient (Kc) model parameter. Ci was measured from June 2016 to March 2017 using stem‐flow and through‐flow gauges within the crop and rain gauges outside the crop. The closest estimated ET to the EC data was the Penman‐Monteith (short grass) model. The Kc values proposed are 0.63 for the early season (March and April), 0.85 for the main growing season (May to September), 1.57 for the late growing season (October and November), and 1.12 over the winter (December to February). These more accurate Kc values will enable better ET estimates with the use of the Penman‐Monteith (short grass) model improving estimates of potential yields and hydrological impacts of land use change. Ci was 24% and remained high during the autumn and winter thereby sustaining significant levels of canopy evaporation and suggesting benefits for winter flood mitigation.  相似文献   

9.
The perennial C4 Miscanthus spp. is used in China for bio‐fuel production and its ecological functions. However, questions arise as to its economic and environmental sustainability in abandoned farmland where the costs should be very low. Little is known about its yield performance and effects on soil properties when it was harvested annually without any inputs in China. To address these questions, an experiment was implemented for 12 years on annually harvested Miscanthus sacchariflorus planted in 2006 and managed without fertilization, irrigation, or any other inputs. We determined biomass yields each year, biomass allocation, and soil properties before and after its cultivation. Biomass yields of M. sacchariflorus reached a peak value (29.67 t/ha) 3 years after cultivation and was maintained at a stable level (averaged 22.22 t/ha) during 2012–2017. Its root shoot ratio increased due to more biomass allocated below‐ground with time. Long‐term cultivation of M. sacchariflorus increased organic carbon contents, pH (for the absence of fertilization), microbial carbon, nitrogen and phosphorus contents, and soil carbon nitrogen ratios (0–100 cm). Soil bulk density was decreased significantly (p < .05) independent of soil depths. Annual harvest did not reduce total nitrogen and phosphorus, available nitrogen, and potassium, but total the potassium content of soil (0–100 cm). Cultivation of M. sacchariflorus increased available phosphorus contents in 40–100 cm soil and reduced that value in 20–40 cm soil. Biological nitrogen fixation provided ~218.74 kg ha?1 year?1 (1 m depth) nitrogen for the system offsetting nitrogen export by biomass harvest and stabilizing nitrogen levels of soil. In conclusion, M. sacchriflorus exhibited sustainable biomass yields and ameliorated soil properties but the decrease of total potassium contents after 12 years’ cultivation without any input. These conclusions could provide important information timely for the government and encourage farmers to promote large‐scale utilization of M. sacchriflorus on the abandoned farmland in China.  相似文献   

10.
Selecting superior clones is the first step for commercial short‐rotation coppice cultures to provide biomass and bioenergy. Till date, such selection for hybrid Populus clones in middle China is absent. Here we describe the growth, aboveground biomass production and cell wall composition of 27 hybrid poplar clones in Henan, China for two 3‐year rotations. Significant variation in these three characteristics over two triennial rotation coppices among the 27 poplar clones was observed. During two 3‐year rotation coppices, clones ‘276’, ‘02‐17’, and ‘599’ showed relatively higher tree heights and larger basal diameters than those of the other clones. However, the most productive clones were ‘36’ and ‘01‐30’. At the end of the second triennial rotation, the aboveground biomass production reached 18 Mg ha?1 year?1. For the cell wall composition analysis, the cellulose contents of clones ‘01‐243’ and ‘2001’ were relatively high, while the xylose contents of clones ‘01‐30’ and ‘65’ were relatively high. Cluster analysis based on height, basal diameter, biomass, heat value, cellulose content, and survival rate revealed five growth potential classes. Accordingly, clones ‘03‐332’, ‘36’, and ‘599’ exhibited high biomass and growth and had the greatest potential to serve as excellent biomass producers in Henan, China. In addition, the expression patterns of 20 key regulatory genes were analyzed, and an integrated coexpression network was constructed. This field trial provides a comprehensive quantification and evaluation of the agronomic performance of 27 poplar clones in Henan, China. The results of this study and the analytical strategies provide an efficient mechanism for selecting clones that will perform well agronomically in local environments. The expression of key genes and the integrated coexpression network provide the molecular mechanisms of poplar biomass performance.  相似文献   

11.
The composition and concentrations of cell wall polysaccharides and phenolic compounds were analyzed in mature stems of several Miscanthus genotypes, in comparison with switchgrass and reed (Arundo donax), and biomass characteristics were correlated with cell wall saccharification efficiency. The highest cellulose content was found in cell walls of M. sinensis‘Grosse Fontaine’ (55%) and in A. donax (47%) and lowest (about 32%) in M. sinensis‘Adagio’. There was little variation in lignin contents across M. sinensis samples (all about 22–24% of cell wall), however, Miscanthus×giganteus (M × g) cell walls contained about 28% lignin, reed – 23% and switchgrass – 26%. The highest ratios of cellulose/lignin and cellulose/xylan were in M. sinensis‘Grosse Fontaine’ across all samples tested. About the same total content of ester‐bound phenolics was found in different Miscanthus genotypes (23–27 μg/mg cell wall), while reed cell walls contained 17 μg/mg cell wall and switchgrass contained a lower amount of ester‐bound phenolics, about 15 μg/mg cell wall. Coumaric acid was a major phenolic compound ester‐bound to cell walls in plants analyzed and the ratio of coumaric acid/ferulic acid varied from 2.1 to 4.3, with the highest ratio being in M × g samples. Concentration of ether‐bound hydroxycinnamic acids varied greatly (about two‐three‐fold) within Miscanthus genotypes and was also the highest in M × g cell walls, but at a concentration lower than ester‐bound hydroxycinnamic acids. We identified four different forms of diferulic acid esters bound to Miscanthus cell walls and their concentration and proportion varied in genotypes analyzed with the 5‐5‐coupled dimer being the predominant type of diferulate in most samples tested. The contents of lignin and ether‐bound phenolics in the cell wall were the major determinants of the biomass degradation caused by enzymatic hydrolysis.  相似文献   

12.
The underground part of a tree is an important carbon sink in forest ecosystems. Understanding biomass allocation between the below‐ and aboveground parts (root:shoot ratios) is necessary for estimation of the underground biomass and carbon pool. Nevertheless, large‐scale biomass allocation patterns and their control mechanisms are not well identified. In this study, a large database of global forests at the community level was compiled to investigate the root:shoot ratios and their responses to environmental factors. The results indicated that both the aboveground biomass (AGB) and belowground biomass (BGB) of the forests in China (medians 73.0 Mg/ha and 17.0 Mg/ha, respectively) were lower than those worldwide (medians 120.3 Mg/ha and 27.7 Mg/ha, respectively). The root:shoot ratios of the forests in China (median = 0.23), however, were not significantly different from other forests worldwide (median = 0.24). In general, the allocation of biomass between the belowground and aboveground parts was determined mainly by the inherent allometry of the plant but also by environmental factors. In this study, most correlations between root:shoot ratios and environmental factors (development parameter, climate, altitude, and soil) were weak but significant (< .01). The allometric model agreed with the trends observed in this study and effectively estimated BGB based on AGB across the entire database.  相似文献   

13.
Stripe rust of winter bread wheat (Triticum aestivum L.) causes substantial grain yield loss in Central Asia. This study involved two replicated field experiments undertaken in 2009–2010 and 2010–2011 winter wheat crop seasons. The first experiment was conducted to determine grain yield reductions on susceptible winter wheat cultivars using single and two sprays of fungicide at Zadoks growth stages Z61–Z69 in two farmers’ fields in Tajikistan and one farmer's field in Uzbekistan. In the second experiment, four different fungicides at two concentrations were evaluated at Zadoks growth stage Z69. These included three products from BASF – Opus (0.5 l/ha and 1.0 l/ha), Platoon (0.5 l/ha and 1.0 l/ha) and Opera (0.75 l/ha and 1.5 l/ha) – and locally used fungicide Titul 390 (0.5 l/ha and 1.0 l/ha). One and two sprays of fungicides did not differ significantly (P > 0.05) in increasing grain yield. Stripe rust reduced grain yield and 1000‐kernel weight (TKW) from 24 to 39% and from 16 to 24%, respectively. The benefits from the two concentrations of the same fungicide did not consistently resulted in significantly higher grain yield, suggesting that the lower concentrations could be more cost effective. Our study provides important information about the selection of fungicides, spray concentrations and number of spray to control stripe rust and increase grain yield. The findings could play an important role in developing stripe rust management approaches such as fungicide rotation and strategic fungicide applications in Central Asian countries.  相似文献   

14.
Biomass from short‐rotation coppice (SRC) of woody perennials is being increasingly used as a bioenergy source to replace fossil fuels, but accurate assessments of the long‐term greenhouse gas (GHG) balance of SRC are lacking. To evaluate its mitigation potential, we monitored the GHG balance of a poplar (Populus) SRC in Flanders, Belgium, over 7 years comprising three rotations (i.e., two 2 year rotations and one 3 year rotation). In the beginning—that is, during the establishment year and during each year immediately following coppicing—the SRC plantation was a net source of GHGs. Later on—that is, during each second or third year after coppicing—the site shifted to a net sink. From the sixth year onward, there was a net cumulative GHG uptake reaching ?35.8 Mg CO2 eq/ha during the seventh year. Over the three rotations, the total CO2 uptake was ?51.2 Mg CO2/ha, while the emissions of CH4 and N2O amounted to 8.9 and 6.5 Mg CO2 eq/ha, respectively. As the site was non‐fertilized, non‐irrigated, and only occasionally flooded, CO2 fluxes dominated the GHG budget. Soil disturbance after land conversion and after coppicing were the main drivers for CO2 losses. One single N2O pulse shortly after SRC establishment contributed significantly to the N2O release. The results prove the potential of SRC biomass plantations to reduce GHG emissions and demonstrate that, for the poplar plantation under study, the high CO2 uptake outweighs the emissions of non‐CO2 greenhouse gases.  相似文献   

15.
Improving biomass yield is a major goal of Miscanthus breeding. We conducted a study on one interspecific Miscanthus sinensis × Miscanthus sacchariflorus F1 population and two intraspecific M. sinensis F1 populations, each of which shared a common parent. A field trial was established at Urbana, IL during spring 2011, and phenotypic data were collected in 2012 and 2013 for fourteen yield traits. Six high‐density parental genetic maps, as well as a consensus genetic map integrating M. sinensis and M. sacchariflorus, were developed via the pseudotestcross strategy for noninbred parents with ≥1214 single‐nucleotide polymorphism markers generated from restriction site‐associated DNA sequencing. We confirmed for the first time a whole‐genome duplication in M. sacchariflorus relative to Sorghum bicolor, similar to that observed previously for M. sinensis. Four quantitative trait locus (QTL) analysis methods for detecting marker‐trait associations were compared: (1) individual parental map composite interval mapping analysis, (2) individual parental map stepwise analysis, (3) consensus map single‐population stepwise analysis and (4) consensus map joint‐population stepwise analysis. These four methods detected 288, 264, 133 and 109 total QTLs, which resolved into 157, 136, 106 and 86 meta‐QTLs based on QTL congruency, respectively, including a set of 59 meta‐QTLs common to all four analysis methods. Composite interval mapping and stepwise analysis co‐identified 118 meta‐QTLs across six parental maps, suggesting high reliability of stepwise regression in QTL detection. Joint‐population stepwise analysis yielded the highest resolution of QTLs compared to the other three methods across all meta‐QTLs. Strong, frequently advantageous transgressive segregation in the three populations indicated a promising future for breeding new higher‐yielding cultivars of Miscanthus.  相似文献   

16.
  • Miscanthus sinensis Anderss. is a good candidate for C4 bioenergy crop development for marginal lands. As one of the characteristics of marginal lands, salinization is a major limitation to agricultural production. The present work aimed to investigate the possible factors involved in the tolerance of M. sinensis C4 photosynthesis to salinity stress.
  • Seedlings of two accessions (salt‐tolerant ‘JM0119’ and salt‐sensitive ‘JM0099’) were subjected to 0 mm NaCl (control) or 250 mm NaCl (salt stress treatment) for 2 weeks. The chlorophyll content, parameters of photosynthesis and chlorophyll a fluorescence, activity of C4 enzymes and expression of C4 genes were measured.
  • The results showed that photosynthesis rate, transpiration rate, chlorophyll content, PSII operating efficiency, coefficient of photochemical quenching, activity of phosphoenolpyruvate carboxylase (PEPC) and pyruvate, orthophosphate dikinase (PPDK) and gene expression of PEPC and PPDK under salinity were higher after long‐term salinity exposure in ‘JM0119’ than in ‘JM0099’, while activity of NADP‐malate dehydrogenase (NADP‐MDH) and NADP‐malic enzyme (NADP‐ME), together with expression of NADP‐MDH and NADP‐ME, were much higher in ‘JM0099’ than in ‘JM0119’.
  • In conclusion, the increased photosynthetic capacity under long‐term salt stress in the salt‐tolerant relative to the salt‐sensitive M. sinensis accession was mainly associated with non‐stomatal factors, such as reduced chlorophyll loss, higher PSII operating efficiency, enhanced activity of PEPC and PPDK and relatively lower activity of NADP‐ME.
  相似文献   

17.
The suitability of miscanthus biomass for anaerobic digestion has already been confirmed by several studies. However, it is rarely used as feedstock in biogas plants, mainly due to uncertainty about the optimal harvest regime with regard to the long‐term methane hectare yield and resilience of the crop to green cutting. The recommended green‐cut date for the only commercially available genotype Miscanthus × giganteus (M×g) ranges from September to November. This timeframe is too broad for agricultural practice and needs to be both narrowed down and further specified for different genotypes. The aim of this study was to identify the most suitable harvest window for an autumn green cut of miscanthus, which delivers both a high dry matter and methane yield while securing the long‐term productivity of the crop. A further objective was to quantify the effect of genotypic differences, such as leaf to stem ratio, on the substrate‐specific biogas and methane yield. For these purposes, a field trial with four genotypes (M×g, GNT1, GNT3, Sin55) was conducted over 2 years (2016/2017) and harvested at 2‐week intervals on three dates between mid‐September to mid‐October. Methane hectare yield ranged from 3,183 m³ CH4 ha?1 a?1 (Sin55) to 5,265 m³ CH4 ha?1 a?1 (M×g), which is mainly influenced by dry matter yield. The substrate‐specific methane yield was higher for the leaf (311.0 ml CH4 (g oDM)‐1) than the stem fraction (285.1 ml CH4 (g oDM)‐1) in all genotypes due to lower lignin content of leaves. Of all genotypes, M×g showed the highest and Sin55 the lowest nutrient use efficiency. We conclude that miscanthus in Germany should be harvested in October to maximize methane yields and nutrient recycling and minimize yield reduction. Additionally, to increase methane hectare yields even further, future miscanthus breeding should focus on a higher leaf proportion.  相似文献   

18.
To improve the efficiency of breeding of Miscanthus for biomass yield, there is a need to develop genomics‐assisted selection for this long‐lived perennial crop by relating genotype to phenotype and breeding value across a broad range of environments. We present the first genome‐wide association (GWA) and genomic prediction study of Miscanthus that utilizes multilocation phenotypic data. A panel of 568 Miscanthus sinensis accessions was genotyped with 46,177 single nucleotide polymorphisms (SNPs) and evaluated at one subtropical and five temperate locations over 3 years for biomass yield and 14 yield‐component traits. GWA and genomic prediction were performed separately for different years of data in order to assess reproducibility. The analyses were also performed for individual field trial locations, as well as combined phenotypic data across groups of locations. GWA analyses identified 27 significant SNPs for yield, and a total of 504 associations across 298 unique SNPs across all traits, sites, and years. For yield, the greatest number of significant SNPs was identified by combining phenotypic data across all six locations. For some of the other yield‐component traits, greater numbers of significant SNPs were obtained from single site data, although the number of significant SNPs varied greatly from site to site. Candidate genes were identified. Accounting for population structure, genomic prediction accuracies for biomass yield ranged from 0.31 to 0.35 across five northern sites and from 0.13 to 0.18 for the subtropical location, depending on the estimation method. Genomic prediction accuracies of all traits were similar for single‐location and multilocation data, suggesting that genomic selection will be useful for breeding broadly adapted M. sinensis as well as M. sinensis optimized for specific climates. All of our data, including DNA sequences flanking each SNP, are publicly available. By facilitating genomic selection in M. sinensis and Miscanthus × giganteus, our results will accelerate the breeding of these species for biomass in diverse environments.  相似文献   

19.
Giant miscanthus (Miscanthus × giganteus Greef and Deuter) and Amur silver grass (Miscanthus sacchariflorus Maxim./Hack) are rhizomatous grasses with a C4 photosynthetic pathway that are widely cultivated as energy crops. For those species to be successfully used in bioenergy generation, their yields have to be maintained at a high level in the long term. The biomass yield (fresh and dry matter [DM] yield) and energy efficiency (energy inputs, energy output, energy gain, and energy efficiency ratio) of giant miscanthus and Amur silver grass were compared in a field experiment conducted in 2007–2017 in North‐Eastern Poland. Both species were characterized by high above‐ground biomass yields, and the productive performance of M. × giganteus was higher in comparison with M. sacchariflorus (15.5 vs. 9.3 Mg DM ha?1 year?1 averaged for 1–11 years of growth). In the first year of the experiment, the energy inputs associated with the production of M. × giganteus and M. sacchariflorus were determined at 70.5 and 71.5 GJ/ha, respectively, and rhizomes accounted for around 78%–79% of total energy inputs. In the remaining years of cultivation, the total energy inputs associated with the production of both perennial rhizomatous grasses reached 13.6–15.7 (M. × giganteus) and 16.9–17.5 GJ ha?1 year?1 (M. sacchariflorus). Beginning from the second year of cultivation, mineral fertilizers were the predominant energy inputs in the production of M. × giganteus (78%–86%) and M. sacchariflorus (80%–82%). In years 2–11, the energy gain of M. × giganteus reached 50 (year 2) and 264–350 GJ ha?1 year?1 (years 3–11), and its energy efficiency ratio was determined at 4.7 (year 2) and 18.6–23.3 (years 3–11). The energy gain and the energy efficiency ratio of M. sacchariflorus biomass in the corresponding periods were determined at 87–234 GJ ha?1 year?1 and 6.1–14.3, respectively. Both grasses are significant and environmentally compatible sources of bioenergy, and they can be regarded as potential energy crops for Central‐Eastern Europe.  相似文献   

20.
Prairie cordgrass (Spartina pectinata Link.) is indigenous throughout most of the continental United States and Canada to 60°N latitude and is well suited to marginal land too wet for maize (Zea mays L.) and switchgrass (Panicum virgatum L.). Evaluations of prairie cordgrass in Europe and North America indicated it has high potential for biomass production, relative to switchgrass, in short‐season areas. Our objective was to describe morphology and biomass production and partitioning in mature stands of ‘Red River’ prairie cordgrass and determine biomass production of natural populations on marginal land. This study was conducted from 2000 to 2008 in eastern South Dakota. Mean biomass production of mature stands of Red River was 12.7 Mg ha?1. Leaves composed >88% of the biomass, and 60% of the tillers had no internodes. Belowground biomass to a depth of approximately 25 cm, not including roots, was 21 Mg ha?1. Tiller density ranged from 683 tillers m?2 for a 10‐year‐old stand to 1140 tillers m?2 for a 4‐year‐old stand. The proaxis was composed of about eight phytomers, with rhizomes originating at proximal nodes and erect tillers at distal nodes. Vegetative propagation was achieved by both phalanx and guerilla growth. Differences among natural populations for biomass were expressed on gravelly marginal land. However, production, averaged across populations, was low (1.37 Mg ha?1) and comparable to ‘Cave‐In‐Rock’ switchgrass (1.67 Mg ha?1) over a 4‐year period. The large carbon storage capacity of prairie cordgrass in proaxes and rhizomes makes it useful for carbon sequestration purposes. Prairie cordgrass should be compared with switchgrass and other C4 perennial grasses along environmental gradients to determine optimum landscape positions for each and to maximize bioenergy production and minimize inputs.  相似文献   

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