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Abstract Accelerating biomass improvement is a major goal of Miscanthus breeding. The development and implementation of genomic‐enabled breeding tools, like marker‐assisted selection (MAS) and genomic selection, has the potential to improve the efficiency of Miscanthus breeding. The present study conducted genome‐wide association (GWA) and genomic prediction of biomass yield and 14 yield‐components traits in Miscanthus sacchariflorus. We evaluated a diversity panel with 590 accessions of M. sacchariflorus grown across 4 years in one subtropical and three temperate locations and genotyped with 268,109 single‐nucleotide polymorphisms (SNPs). The GWA study identified a total of 835 significant SNPs and 674 candidate genes across all traits and locations. Of the significant SNPs identified, 280 were localized in mapped quantitative trait loci intervals and proximal to SNPs identified for similar traits in previously reported Miscanthus studies, providing additional support for the importance of these genomic regions for biomass yield. Our study gave insights into the genetic basis for yield‐component traits in M. sacchariflorus that may facilitate marker‐assisted breeding for biomass yield. Genomic prediction accuracy for the yield‐related traits ranged from 0.15 to 0.52 across all locations and genetic groups. Prediction accuracies within the six genetic groupings of M. sacchariflorus were limited due to low sample sizes. Nevertheless, the Korea/NE China/Russia (N = 237) genetic group had the highest prediction accuracy of all genetic groups (ranging 0.26–0.71), suggesting that with adequate sample sizes, there is strong potential for genomic selection within the genetic groupings of M. sacchariflorus. This study indicated that MAS and genomic prediction will likely be beneficial for conducting population‐improvement of M. sacchariflorus.

Abstract Miscanthus is a genus of perennial grasses native to East Asia that shows promise as a biofuel energy source. Breeding efforts for increasing biofuel capability in this genus have focused on two species, namely M. sinensis (Msi) and M. sacchariflorus (Msa). For these efforts to succeed, it is critical that both Msi and Msa, as well as their interspecific crosses, can be grown at a wide range of latitudes. Therefore, the purpose of this study was to investigate how well existing data from Msi and Msa trials grown at locations throughout the northern hemisphere can train state‐of‐the‐art genomic selection (GS) models to predict genomic estimated breeding values (GEBVs) of dry yield for untested Msi and Msa accessions in untested environments. We found that accounting for genotype by environment interaction in the GS model did not notably improve predictive ability. Additionally, we observed that locations at lower latitudes showed higher predictive ability relative to locations at higher latitudes. These results suggest that it is crucial to increase the number of trial locations at higher latitude locations to investigate the source of this correlation. This will make it possible to train GS models using data from environments that are similar to growing conditions at the locations targeted by Msi and Msa breeders. Such an increase of trial locations in target environments could pave the way toward advancing breeding efforts for overwintering ability in Msi and Msa, and ultimately support the potential of Miscanthus as a biofuel crop.

Abstract Discovery and analysis of genetic variants underlying agriculturally important traits are key to molecular breeding of crops. Reduced representation approaches have provided cost‐efficient genotyping using next‐generation sequencing. However, accurate genotype calling from next‐generation sequencing data is challenging, particularly in polyploid species due to their genome complexity. Recently developed Bayesian statistical methods implemented in available software packages, polyRAD, EBG, and updog, incorporate error rates and population parameters to accurately estimate allelic dosage across any ploidy. We used empirical and simulated data to evaluate the three Bayesian algorithms and demonstrated their impact on the power of genome‐wide association study (GWAS) analysis and the accuracy of genomic prediction. We further incorporated uncertainty in allelic dosage estimation by testing continuous genotype calls and comparing their performance to discrete genotypes in GWAS and genomic prediction. We tested the genotype‐calling methods using data from two autotetraploid species, Miscanthus sacchariflorus and Vaccinium corymbosum, and performed GWAS and genomic prediction. In the empirical study, the tested Bayesian genotype‐calling algorithms differed in their downstream effects on GWAS and genomic prediction, with some showing advantages over others. Through subsequent simulation studies, we observed that at low read depth, polyRAD was advantageous in its effect on GWAS power and limit of false positives. Additionally, we found that continuous genotypes increased the accuracy of genomic prediction, by reducing genotyping error, particularly at low sequencing depth. Our results indicate that by using the Bayesian algorithm implemented in polyRAD and continuous genotypes, we can accurately and cost‐efficiently implement GWAS and genomic prediction in polyploid crops.

Abstract Demand for sustainably produced biomass is expected to increase with the need to provide renewable commodities, improve resource security and reduce greenhouse gas emissions in line with COP26 commitments. Studies have demonstrated additional environmental benefits of using perennial biomass crops (PBCs), when produced appropriately, as a feedstock for the growing bioeconomy, including utilisation for bioenergy (with or without carbon capture and storage). PBCs can potentially contribute to Common Agricultural Policy (CAP) (2023–27) objectives provided they are carefully integrated into farming systems and landscapes. Despite significant research and development (R&D) investment over decades in herbaceous and coppiced woody PBCs, deployment has largely stagnated due to social, economic and policy uncertainties. This paper identifies the challenges in creating policies that are acceptable to all actors. Development will need to be informed by measurement, reporting and verification (MRV) of greenhouse gas emissions reductions and other environmental, economic and social metrics. It discusses interlinked issues that must be considered in the expansion of PBC production: (i) available land; (ii) yield potential; (iii) integration into farming systems; (iv) R&D requirements; (v) utilisation options; and (vi) market systems and the socio‐economic environment. It makes policy recommendations that would enable greater PBC deployment: (1) incentivise farmers and land managers through specific policy measures, including carbon pricing, to allocate their less productive and less profitable land for uses which deliver demonstrable greenhouse gas reductions; (2) enable greenhouse gas mitigation markets to develop and offer secure contracts for commercial developers of verifiable low‐carbon bioenergy and bioproducts; (3) support innovation in biomass utilisation value chains; and (4) continue long‐term, strategic R&D and education for positive environmental, economic and social sustainability impacts.

Abstract Miscanthus is a high‐yielding bioenergy crop that is broadly adapted to temperate and tropical environments. Commercial cultivation of Miscanthus is predominantly limited to a single sterile triploid clone of Miscanthus × giganteus, a hybrid between Miscanthus sacchariflorus and M. sinensis. To expand the genetic base of M. × giganteus, the substantial diversity within its progenitor species should be used for cultivar improvement and diversification. Here, we phenotyped a diversity panel of 605 M. sacchariflorus from six previously described genetic groups and 27 M. × giganteus genotypes for dry biomass yield and 16 yield‐component traits, in field trials grown over 3 years at one subtropical location (Zhuji, China) and four temperate locations (Foulum, Denmark; Sapporo, Japan; Urbana, Illinois; and Chuncheon, South Korea). There was considerable diversity in yield and yield‐component traits among and within genetic groups of M. sacchariflorus, and across the five locations. Biomass yield of M. sacchariflorus ranged from 0.003 to 34.0 Mg ha−1 in year 3. Variation among the genetic groups was typically greater than within, so selection of genetic group should be an important first step for breeding with M. sacchariflorus. The Yangtze 2x genetic group (=ssp. lutarioriparius) of M. sacchariflorus had the tallest and thickest culms at all locations tested. Notably, the Yangtze 2x genetic group's exceptional culm length and yield potential were driven primarily by a large number of nodes (>29 nodes culm−1 average over all locations), which was consistent with the especially late flowering of this group. The S Japan 4x, the N China/Korea/Russia 4x, and the N China 2x genetic groups were also promising genetic resources for biomass yield, culm length, and culm thickness, especially for temperate environments. Culm length was the best indicator of yield potential in M. sacchariflorus. These results will inform breeders' selection of M. sacchariflorus genotypes for population improvement and adaptation to target production environments.

Abstract Morphine induces spinal 5‐hydroxytryptamine (5‐HT) release, but the role and mechanism of the spinal 5‐HT release induced by morphine are not well understood. The purpose of this study was to define the role and mechanism of spinal 5‐HT release induced by oral morphine. We also examined whether persistent pain affected the spinal 5‐HT release induced by oral morphine. Spinal 5‐HT release was measured using microdialysis of lumbar cerebrospinal fluid (CSF). Two opioids, morphine and oxycodone, were orally administered and 5‐HT release was measured in awake rats. Naloxone and β‐funaltrexamine (β‐FNA) were used to determine whether the effect of morphine on 5‐HT release was mediated by opioid receptor activation. To study persistent pain, a formalin test was used. At 45 min after oral morphine administration, the formalin test was started and spinal 5‐HT release was measured. Oral morphine, but not oral oxycodone, increased 5‐HT release at the spinal cord to approximately 4000% of the baseline value. This effect of morphine was not antagonized by either naloxone or β‐FNA at a dose that antagonized the antinociceptive effect of morphine. Formalin‐induced persistent pain itself had no effect on spinal 5‐HT release but enhanced the oral morphine‐induced spinal 5‐HT release. Oral morphine‐induced spinal 5‐HT release was not mediated by opioid receptor activation. Spinal 5‐HT induced by oral morphine did not play a major role in the antinociceptive effect of morphine in the hot plate test. Persistent pain increased oral morphine‐induced spinal 5‐HT release.

Biomass fuel is promoted toward a target of net GHG zero emissions in 2050 that Japanese government announced last October 2020. Using biomass pellets in pulverized coal fired power plants are recently increasing. IHI has supplied the co-firing power plants of 30cal% or more biomass pellets with coal. The biomass particles after pulverization by biomass mills are transported to the burners through the fuel pipes by air. Deposition of the biomass particles in a fuel pipe on the way to a burner make a serious impact on the stable combustion and boiler operation. It is important to understand conditions of occurring deposition in order to prevent the deposition of the biomass particles in the fuel pipe. However, various types of pellets are used, and conditions of occurring deposition is depending on the size and shape of the biomass particles. In this test, the transportation of two types of biomass particles is observed by using a transparent horizontal pipe with 30m length. This result suggests that conditions of occurring deposition is different depending on the shape of biomass particles.

The perennial grass Miscanthus is a promising biomass crop. Here, via genomics and transcriptomics, the authors reveal its allotetraploid origin, characterize gene expression associated with rhizome development and nutrient recycling, and describe the hybrid origin of the triploid M. x giganteus.

Miscanthus is a perennial grass with potential for lignocellulosic ethanol production. To ensure its utility for this purpose, breeding efforts should focus on increasing genetic diversity of the nothospecies Miscanthus × giganteus (M×g) beyond the single clone used in many programs. Germplasm from the corresponding parental species M. sinensis (Msi) and M. sacchariflorus (Msa) could theoretically be used as training sets for genomic prediction of M×g clones with optimal genomic estimated breeding values for biofuel traits. To this end, we first showed that subpopulation structure makes a substantial contribution to the genomic selection (GS) prediction accuracies within a 538-member diversity panel of predominately Msi individuals and a 598-member diversity panels of Msa individuals. We then assessed the ability of these two diversity panels to train GS models that predict breeding values in an interspecific diploid 216-member M×g F2 panel. Low and negative prediction accuracies were observed when various subsets of the two diversity panels were used to train these GS models. To overcome the drawback of having only one interspecific M×g F2 panel available, we also evaluated prediction accuracies for traits simulated in 50 simulated interspecific M×g F2 panels derived from different sets of Msi and diploid Msa parents. The results revealed that genetic architectures with common causal mutations across Msi and Msa yielded the highest prediction accuracies. Ultimately, these results suggest that the ideal training set should contain the same causal mutations segregating within interspecific M×g populations, and thus efforts should be undertaken to ensure that individuals in the training and validation sets are as closely related as possible.

The mechanism by which acetaminophen produces its analgesic effects is not fully understood. One possible mechanism is the activation of the spinal 5-hydroxytryptamine (5-HT) receptor, although direct evidence of spinal 5-HT release has not yet been reported. N-arachidonoylphenolamine (AM404), a metabolite of acetaminophen, is believed to be the key substance that contributes to the analgesic effects of acetaminophen. In this study, we examined whether acetaminophen and AM404 induce spinal 5-HT release and the mechanism through which spinal 5-HT receptor activation exerts analgesic effects in a rat formalin test in an inflammatory pain model. Spinal 5-HT release was examined by intrathecal microdialysis in conscious and freely moving rats. Acetaminophen was administered orally, and AM404 was administered intracerebroventricularly. In rat formalin tests, oral acetaminophen and intracerebroventricular AM404 induced significant spinal 5-HT release and produced analgesic effects. The analgesic effect of oral acetaminophen was partially antagonized by intrathecal administration of WAY100135 (a 5-HT1A receptor antagonist) and SB269970 (a 5-HT7 receptor antagonist). In contrast, the analgesic effect of intracerebroventricular AM404 was completely antagonized by WAY100135, while SB269970 had no effect. Our data suggest that while oral acetaminophen and intracerebroventricular AM404 activate the spinal 5-HT system, the role of the spinal 5-HT system activated by oral acetaminophen differs from that activated by intracerebroventricular AM404.

Abstract Although commercial sugarcane (Saccharum spp. hybrid) produces large biomass yields, its lack of cold tolerance limits its cultivation to the tropics and subtropics. In contrast, sugarcane's close relative, Miscanthus, tolerates low temperatures. We studied 18 miscane genotypes, derived from hybridizations between two genotypes of sugarcane and two genotypes of Miscanthus (one each of M. sinensis and M. sacchariflorus). In an initial greenhouse experiment on long‐duration chilling stress (12–13°C day/7–9°C night), photosynthetic rates of the Miscanthus parents were significantly higher than the sugarcane parents after 7 days of chilling and were more than double by 14 days. The Miscanthus also retained more of their prechilling (22–25°C day/13–15°C night) photosynthetic rates (68%–72% 7 days, 64%–66% 14 days) than the sugarcanes (27% 7 days, 19%–20% 14 days). Seven of 18 miscanes exhibited higher photosynthetic rates than their sugarcane parents after 7 days of chilling, whereas after 14 days only four miscane genotypes had significantly higher photosynthetic rates than their sugarcane parents, but notably two of these did not differ from their highly tolerant Miscanthus parents. In a subsequent growth chamber experiment to evaluate short‐duration chilling stress and postchilling recovery, three miscanes representing the range of responses observed in the greenhouse experiment were compared with their parents. After 4 days of chilling (12/7°C day/night), the miscanes retained between 45% and 60% of their prechilling photosynthetic rate, with the best entry not significantly different from its Miscanthus parent (66%), and all three miscanes performed significantly better than the sugarcane parents (32%–33% for sugarcanes). After 7 days of postchilling recovery (26/18°C day/night), the Miscanthus parents and two of the miscanes fully recovered their prechilling photosynthetic rates but the sugarcane parents only recovered 69%–73% of their prechilling rates. Thus, genes from Miscanthus can be used to improve chilling tolerance of sugarcane via introgression.

Abstract 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.

Abstract Overwintering ability is an important selection criterion for Miscanthus breeding in temperate regions. Insufficient overwintering ability of the currently leading Miscanthus biomass cultivar, M. ×giganteus (M×g) ‘1993–1780', in regions where average annual minimum temperatures are −26.1°C (USDA hardiness zone 5) or lower poses a pressing need to develop new cultivars with superior cold tolerance. To facilitate breeding of Miscanthus, this study characterized phenotypic and genetic variation of overwintering ability in an M. sinensis germplasm panel consisting of 564 accessions, evaluated in field trials at three locations in North America and two in Asia. Genome‐wide association (GWA) and genomic prediction analyses were performed. The Korea/N China M. sinensis genetic group is a valuable gene pool for cold tolerance. The Yangtze‐Qinling, Southern Japan, and Northern Japan genetic groups were also potential sources of cold tolerance. A total of 73 marker–trait associations were detected for overwintering ability. Estimated breeding value for overwintering ability based on these 73 markers could explain 55% of the variation for first winter overwintering ability among M. sinensis. Average genomic prediction ability for overwintering ability across 50 fivefold cross‐validations was high (~0.73) after accounting for population structure. Common genomic regions for overwintering ability were detected by GWA analyses and a previous parallel QTL mapping study using three interconnected biparental F1 populations. One QTL on Miscanthus LG 8 encompassed five GWA hits and a known cold‐responsive gene, COR47. The other overwintering ability QTL on Miscanthus LG 11 contained two GWA hits and three known cold stress‐related genes, carboxylesterase 13 (CEX13), WRKY2 transcription factor, and cold shock domain (CSDP1). Miscanthus accessions collected from high latitude locations with cold winters had higher rates of overwintering, and more alleles for overwintering, than accessions collected from southern locations with mild winters.

Abstract 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.

Miscanthus is a close relative of Saccharum and a potentially valuable genetic resource for improving sugarcane. Differences in flowering time within and between Miscanthus and Saccharum hinders intra- and interspecific hybridizations. A series of greenhouse experiments were conducted over three years to determine how to synchronize flowering time of Saccharum and Miscanthus genotypes. We found that day length was an important factor influencing when Miscanthus and Saccharum flowered. Sugarcane could be induced to flower in a central Illinois greenhouse using supplemental lighting to reduce the rate at which days shortened during the autumn and winter to 1 min d-1, which allowed us to synchronize the flowering of some sugarcane genotypes with Miscanthus genotypes primarily from low latitudes. In a complementary growth chamber experiment, we evaluated 33 Miscanthus genotypes, including 28 M. sinensis, 2 M. floridulus, and 3 M. ×giganteus collected from 20.9° S to 44.9° N for response to three day lengths (10 h, 12.5 h, and 15 h). High latitude-adapted M. sinensis flowered mainly under 15 h days, but unexpectedly, short days resulted in short, stocky plants that did not flower; in some cases, flag leaves developed under short days but heading did not occur. In contrast, for M. sinensis and M. floridulus from low latitudes, shorter day lengths typically resulted in earlier flowering, and for some low latitude genotypes, 15 h days resulted in no flowering. However, the highest ratio of reproductive shoots to total number of culms was typically observed for 12.5 h or 15 h days. Latitude of origin was significantly associated with culm length, and the shorter the days, the stronger the relationship. Nearly all entries achieved maximal culm length under the 15 h treatment, but the nearer to the equator an accession originated, the less of a difference in culm length between the short-day treatments and the 15 h day treatment. Under short days, short culms for high-latitude accessions was achieved by different physiological mechanisms for M. sinensis genetic groups from the mainland in comparison to those from Japan; for mainland accessions, the mechanism was reduced internode length, whereas for Japanese accessions the phyllochron under short days was greater than under long days. Thus, for M. sinensis, short days typically hastened floral induction, consistent with the expectations for a facultative short-day plant. However, for high latitude accessions of M. sinensis, days less than 12.5 h also signaled that plants should prepare for winter by producing many short culms with limited elongation and development; moreover, this response was also epistatic to flowering. Thus, to flower M. sinensis that originates from high latitudes synchronously with sugarcane, the former needs day lengths >12.5 h (perhaps as high as 15 h), whereas that the latter needs day lengths

Miscanthus-dominated semi-natural grasslands in Japan appear to store considerable amounts of soil C. To estimate the long-term effect of Miscanthus vegetation on the accumulation of soil carbon by soil biota degradation in its native range, we measured total soil C from the surface to a 1.2 m depth along a catena toposequence in three annually burned grasslands in Japan: Kawatabi, Soni, and Aso. Soil C stock was estimated using a radiocarbon age and depth model, resulting in a net soil C accumulation rate in the soil. C4-plant contribution to soil C accumulation was further estimated by δ13C of soil C. The range of total soil C varied among the sites (i.e., Kawatabi: 379–638 Mg, Soni: 249–484, and Aso: 372–408 Mg C ha−1). Catena position was a significant factor at Kawatabi and Soni, where the toe slope soil C accumulation exceeded that of the summit. The soil C accumulation rate of the whole horizon in the grasslands, derived C mainly from C4 plant species, was 0.05 ± 0.02 (Average ± SE), 0.04 ± 0.00, and 0.24 ± 0.04 Mg C ha−1 yr−1 in Kawatabi, Soni, and Aso, respectively. Potential exists for long-term sequestration of C under M. sinensis, but the difference in the C accumulation rate can be influenced by the catena position and the amount of vegetation.

The demand for renewable energy resources, such as Miscanthus spp., has increased significantly in temperate regions. Miscanthus spp. has the potential to mitigate GHG emissions by replacing fossil fuels and sequestering carbon in soil. However, the biomass yield and C sequestration performance of Miscanthus spp. varies by climate, soil type, management practices, and land-use history. Therefore, there is a need for site-specific research on biomass yield and C sequestration of Miscanthus × giganteus (M × g). An alternative to M × g is the seed-propagated Miscanthus sinensis which could be another option as a bioenergy crop. The objective of this study was to assess the C sequestration rates and biomass yield performance of these two Miscanthus spp. The C sequestration rates were measured in side-by-side comparison plots using the 13C natural abundance technique. The results revealed C sequestration rates of M × g and M. sinensis were 1.96 ± 0.82 and 0.99 ± 0.21 Mg C ha−1 year−1 over 6 years. The average biomass yields of M × g and M. sinensis from 2010 to 2015 were 25.6 ± 0.2 and 31.2 ± 0.5 Mg ha−1 year−1, respectively. It can be concluded that M. sinensis has a higher yield while M × g has a higher potential for immediate C sequestration in cool regions such as Northern Japan.

Miscanthus, a high-yielding, warm-season C4 grass, shows promise as a potential bioenergy crop in temperate regions. However, drought may restrain productivity of most genotypes. In this study, total 29 Miscanthus genotypes of East-Asian origin were screened for drought tolerance with two methods, a dry-down treatment in two locations and a system where soil moisture content (SMC) was maintained at fixed levels using an automatic irrigation system in one location. One genotype, Miscanthus sinensis PMS-285, showed relatively high drought-tolerance capacity under moderate drought stress. Miscanthus sinensis PMS-285, aligned with the M. sinensis ‘Yangtze-Qinling’ genetic cluster, had relatively high principal component analysis ranking values in both two locations experiments, Hokkaido University and Brigham Young University. Genotypes derived from the ‘Yangtze-Qinling’ genetic cluster showed relatively greater photosynthetic performance than other genetic clusters, suggesting germplasm from this group could be a potential source of drought-tolerant plant material. Diploid genotypes showed stronger drought tolerance than tetraploid genotypes, suggesting ploidy could be an influential factor for this trait. Of the two methods, the dry-down treatment appears more suitable for selecting drought-tolerant genotypes given that it reflects water-stress conditions in the field. However, the fixed-SMC experiment may be good for understanding the physiological responses of plants to relatively constant water-stress levels.

While the efforts to control global warming are being strengthened all over the world, expectations for CO2 Capture, Utilization and Storage (CCUS) technology for coal fired power plants are increasing. IHI has been working on development of oxyfuel-combustion technology since 1989 with the aim of easily capturing and storage CO2 emitted from coal fired power plants. For the demonstration of oxyfuel-combustion technology, IHI participated in the Callide Oxyfuel Project with collaboration between Australian and Japanese under the financial support of Australian, Queensland state and Japanese governments. In the project, the oxyfuel-combustion process was applied to the existing coal power plant in Queensland, Australia, and demonstration was carried out and successfully completed without any significant technical barrier to commercialization in March, 2015. In Oxyfuel-combustion, the coal-fired boiler is operated with an inlet O2 content of 27 vol% in order to achieve the same furnace heat transfer as in conventional air-firing. The first outcome of oxyfuel-combustion is a significant reduction in NOx production, typically 60% reduction, measured in mgNOx/MJcoal. The second outcome of oxyfuel-combustion is a reduction in the actual volumetric flow of flue gas, typically a 60% to 70% reduction in gas flow measured as m3/h, and a proportionate increase in the CO2 content of the flue gas from ~ 15 vol% (dry) in airfiring mode to 70 to 80 vol% (dry) in Oxyfuel mode. In addition, CO2 product from the Callide Oxyfuel Project was injected into the Paaratte formation in the Otway Basin (Victoria) to investigate the geochemical effects of CO2 (normal product) and CO2 with added impurities. The recent research and development about characteristics of roller mill and electrical precipitator using combustion test facilities for the flexibility of plant design and the current commercialization activities of oxyfuel power plant are introduced in this paper.

In Japan, most scholarly journals have been published by scientific societies as in other Asian countries. In those days, Japanese and English language articles were commonly found within the same issue of an academic journal published by scientific societies. Many societies of natural sciences started to publish separate periodicals of international journals with an English version and a domestic Japanese version 20 years ago due to the internationalization of the scientific community. The Japanese Society of Grassland Science has also published both an international journal called Grassland Science and a domestic journal called Japanese Journal of Grassland Science (Nihon Sochigakkai Shi) since 2005. The first impact factor for Grassland Science was announced in 2013. International foreign handling editors represent more than half of all handling editors covering the world. Thus, recently, the number of submissions from foreign countries, especially from China, has drastically increased. With the increase in submissions, it becomes difficult to edit a journal professionally because the editors are generally professors in universities and scientists in national institutes who work as part-time volunteer editors and have been changed frequently. The decrease in the number of members is also a serious problem in many societies of agriculture sciences. The construction of an Asian network for scientific information may be one direction in the near future. Additionally, it is be necessary to change to open access journals in order to stabilize the publishing management of the journals.

Leaf water content is one of the most common physiological parameters limiting efficiency of photosynthesis and biomass productivity in plants including Miscanthus. Therefore, it is of great significance to determine or predict the water content quickly and non-destructively. In this study, we explored the relationship between leaf water content and diffuse reflectance spectra in Miscanthus. Three multivariate calibrations including partial least squares (PLS), least squares support vector machine regression (LSSVR), and radial basis function (RBF) neural network (NN) were developed for the models of leaf water content determination. The non-linear models including RBF_LSSVR and RBF_NN showed higher accuracy than the PLS and Lin_LSSVR models. Moreover, 75 sensitive wavelengths were identified to be closely associated with the leaf water content in Miscanthus. The RBF_LSSVR and RBF_NN models for predicting leaf water content, based on 75 characteristic wavelengths, obtained the high determination coefficients of 0.9838 and 0.9899, respectively. The results indicated the non-linear models were more accurate than the linear models using both wavelength intervals. These results demonstrated that visible and near-infrared (VIS/NIR) spectroscopy combined with RBF_LSSVR or RBF_NN is a useful, non-destructive tool for determinations of the leaf water content in Miscanthus, and thus very helpful for development of drought-resistant varieties in Miscanthus.

The feasibility of visible and near infrared (NIR) spectroscopy as tool to classify Miscanthus samples was explored in this study. Three types of Miscanthus plants, namely, M. sinensis, M. sacchariflorus and M. fIoridulus, were analyzed using a NIR spectrophotometer. Several classification models based on the NIR spectra data were developed using line discriminated analysis (LDA), partial least squares (PLS), least squares support vector machine regression (LSSVR), radial basis function (RBF) and neural network (NN). The principal component analysis (PCA) presented rough classification with overlapping samples, while the models of Line_LSSVR, RBF_LSSVR and RBF_NN presented almost same calibration and validation results. Due to the higher speed of Line_LSSVR than RBF_LSSVR and RBF_NN, we selected the line_LSSVR model as a representative. In our study, the model based on line_LSSVR showed higher accuracy than LDA and PLS models. The total correct classification rates of 87.79 and 96.51% were observed based on LDA and PLS model in the testing set, respectively, while the line_LSSVR showed 99.42% of total correct classification rate. Meanwhile, the lin_LSSVR model in the testing set showed correct classification rate of 100, 100 and 96.77% for M. sinensis, M. sacchariflorus and M. fIoridulus, respectively. The lin_LSSVR model assigned 99.42% of samples to the right groups, except one M. fIoridulus sample. The results demonstrated that NIR spectra combined with a preliminary morphological classification could be an effective and reliable procedure for the classification of Miscanthus species.

In 2013, CO2 levels surpassed 400 ppm for the first time in recorded history. So, we are facing global warming due to the increase levels of atmospheric carbon dioxide (CO2). As a method of reducing CO2 emissions from the thermal power plants, there are carbon dioxide capture and storage (CCS) technologies. Oxyfuel combustion is one of the CO2 Capture technologies and IHI have developed it since 1989. Then, Callide Oxyfuel Project commenced to apply oxyfiring technology in an existing coal fired power plant and to demonstrate an oxyfuel power plant in March, 2008. Demonstration began in 2012 after existing boiler was retrofitted. During the demonstration for approximately three years, many tests were conducted and many data were collected for commercial use. As a result, we confirmed characteristics of oxyfiring such as total heat absorption, combustion characteristics, emissions of NOx, SOx, carbon-in-ash, operational flexibility from 15MWe (50%L) to 30MWe (100%L) and behavior of injected CO2 at the injection site. Total heat absorption of the boiler under oxyfiring was 2 to 3MW higher because of decreasing heat loss in flue gas and rising temperature of boiler feed water by a flue gas cooler. NO was decomposed in the furnace under oxyfiring because flue gas was recirculated. On the other hand, reaction between SO2 and absorbent such as Ca, Mg in ash was not so active regardless of high concentrated SO2 under oxyfiring. Carbon-in-ash was almost 40%~70% in oxyfirng compared with in airfiring because of longer residence time in the furnace. Operational flexibility is important to control oxyfiring operation and it was confirmed that oxyfiring can be operated as well as airfiring. In this paper, operational results are presented in Callide Oxyfuel Project.

Flowering time is a key target trait for extending the vegetative phase to increase biomass in bioenergy crops such as perennial C4 grasses. Molecular genetic studies allow the identification of genes involved in the control of flowering in different species. Some regulatory factors of the Arabidopsis pathway are conserved in other plant species such as grasses. However, differences in the function of particular genes confer specific responses to flowering. One of the major pathways is photoperiod regulation, based on the interaction of the circadian clock and environmental light signals. Depending on their requirements for day-length plants can be classified as long-day (LD), short-day (SD), and day-neutral. The CONSTANS (CO) and Heading Date 1 (Hd1), orthologos genes, are central regulators in the flowering of Arabidopsis and rice, LD and SD plants, respectively. Additionally, Early heading date 1 (Ehd1) induces the expression of Heading date 3a (Hd3a), conferring SD promotion and controls Rice Flowering Locus T 1 (RFT1) in LD conditions, independently of Hd1. Nevertheless, the mechanisms promoting flowering in perennial bioenergy crops are poorly understood. Recent progress on the regulatory network of important gramineous crops and components involved in flowering control will be discussed.