Biomass production of herbaceous energy crops in the United States: field trial results and yield potential maps from the multiyear regional feedstock partnership

Current knowledge of yield potential and best agronomic management practices for perennial bioenergy grasses is primarily derived from small-scale and short-term studies, yet these studies inform policy at the national scale. In an effort to learn more about how bioenergy grasses perform across multiple locations and years, the U.S. Department of Energy (US DOE)/Sun Grant Initiative Regional Feedstock Partnership was initiated in 2008. The objectives of the Feedstock Partnership were to (1) provide a wide range of information for feedstock selection (species choice) and management practice options for a variety of regions and (2) develop national maps of potential feedstock yield for each of the herbaceous species evaluated. The Feedstock Partnership expands our previous understanding of the bioenergy potential of switchgrass, Miscanthus, sorghum, energycane, and prairie mixtures on Conservation Reserve Program land by conducting long-term, replicated trials of each species at diverse environments in the U.S. Trials were initiated between 2008 and 2010 and completed between 2012 and 2015 depending on species. Field-scale plots were utilized for switchgrass and Conservation Reserve Program trials to use traditional agricultural machinery. This is important as we know that the smaller scale studies often overestimated yield potential of some of these species. Insufficient vegetative propagules of energycane and Miscanthus prohibited farm-scale trials of these species. The Feedstock Partnership studies also confirmed that environmental differences across years and across sites had a large impact on biomass production. Nitrogen application had variable effects across feedstocks, but some nitrogen fertilizer generally had a positive effect. National yield potential maps were developed using PRISM-ELM for each species in the Feedstock Partnership. This manuscript, with the accompanying supplemental data, will be useful in making decisions about feedstock selection as well as agronomic practices across a wide region of the country

Ancient and Modern Genomes Unravel the Evolutionary History of the Rhinoceros Family

Only five species of the once-diverse Rhinocerotidae remain, making the reconstruction of their evolutionary history a challenge to biologists since Darwin. We sequenced genomes from five rhinoceros species (three extinct and two living), which we compared to existing data from the remaining three living species and a range of outgroups. We identify an early divergence between extant African and Eurasian lineages, resolving a key debate regarding the phylogeny of extant rhinoceroses. This early Miocene (∼16 million years ago [mya]) split post-dates the land bridge formation between the Afro-Arabian and Eurasian landmasses. Our analyses also show that while rhinoceros genomes in general exhibit low levels of genome-wide diversity, heterozygosity is lowest and inbreeding is highest in the modern species. These results suggest that while low genetic diversity is a long-term feature of the family, it has been particularly exacerbated recently, likely reflecting recent anthropogenic-driven population declines. © 2021 The Authors.The authors acknowledge support from the Science for Life Laboratory, the Garvan Institute of Medical Research, the Knut and Alice Wallenberg Foundation, and the National Genomics Infrastructure funded by the Swedish Research Council and Uppsala Multidisciplinary Center for Advanced Computational Science for assistance with massively parallel sequencing and access to the UPPMAX computational infrastructure. We thank the Natural History Museum at the University of Oslo for providing the Javan rhinoceros sample. We thank the Museum of the Institute of Plant and Animal Ecology (UB RAS, Ekaterinburg) for providing the sample of Siberian unicorn. M.T.P.G. was supported by European Research Council (ERC) Consolidator grant 681396 (Extinction Genomics). E.D.L. was supported by Independent Research Fund Denmark grant 8021-00218B . A.C. was supported by an Australian Research Council Laureate Fellowship ( FL140100260 ). T.M.B. is supported by funding from the ERC under the European Union’s Horizon 2020 research and innovation program (grant agreement 864203 ), grant BFU2017-86471-P ( MINECO /FEDER, UE), “Unidad de Excelencia María de Maeztu” funded by the AEI ( CEX2018-000792-M ), Howard Hughes International Early Career, and Secretaria d’Universitats i Recerca and CERCA Programme del Departament d’Economia i Coneixement de la Generalitat de Catalunya ( GRC 2017 SGR 880 ). L.D. was supported by the Swedish Research Council ( 2017-04647 ) and Formas ( 2018-01640 ). We thank Dmitry Bogdanov and Roger Hall for giving us permission to use their rhinoceros artwork

Biological activity of some oxygenated sterols.

A group of oxygenated sterols has been identified as potent and specific inhibitors of sterol biosynthesis. The ability of these compounds to inhibit sterol synthesis in cultured cells and the ineffectiveness of cholesterol under the same conditions suggest that feedback regulation of sterol biosynthesis may be brought about by an oxygenated sterol rather than by cholesterol. The nature of the regulatory sterol may vary in different cells with their specific requirements for cholesterol as a structural component or as a precursor of other steroid products. The use of oxygenated sterols to block sterol synthesis in cultured cells provides new information regarding the role of sterol in cell membrane structure and function. For example, de novo sterol synthesis is required for DNA synthesis and cell division by some cultured cells. Studies with cultured cells, and with rats and mice in vivo, suggest that oxygenated sterols could be of value in the treatment of several important human diseases

Alteration of 86Rb+ influx and efflux following depletion of membrane sterol in L-cells.

Ouabain-sensitive uptake of 86Rb+ (an analogue of K+) was enhanced in L-cells that had been treated with 25-hydroxycholesterol or 7-ketocholesterol in order to deplete their sterol concentration. Ouabain-insensitive Rb+ efflux also increased in the sterol-depleted cells and the intracellular concentration of K+ diminished while the concentration of Na+ increased. All of these effects of 25-hydroxycholesterol were counteracted by the addition of mevalonate to the culture medium. Despite the evidence for increased active Rb+ transport in the 25-hydroxycholesterol-treated cells, the level of sodium and potassium ion-activated adenosine triphosphatase ((Na+ + K+)-activated ATPase) activity measured in homogenates and plasma membrane preparations from the treated cells was not significantly different from the control values. Rb+ uptake was more sensitive to ouabain inhibition in sterol-depleted cells than in control cells, although ATPase activity in plasma membrane fractions isolated from treated cells was not more sensitive to ouabain inhibition than was that from control cells. It is possible that the ability of the oxygenated sterols to inhibit DNA synthesis and cell division (Kandutsch, A. A., and Chen, H. W. (1977) J. Biol. Chem. 252, 409-415) is related to their effects upon cellular ion transport

Relationship between sterol synthesis and DNA synthesis in phytohemagglutinin-stimulated mouse lymphocytes.

Incubation of peripheral blood or isolated lymphocytes of C57L/J mice with phytohemagglutinin stimulated the incorporation of thymidine into DNA of lymphocytes as they transformed into large lymphoblasts. DNA synthesis began after about 24 hr of incubation and reached a peak at 48 hours. The de-novo synthesis of sterols from acetate was stimulated much earlier, at 4 hr of incubation, and the rate reached a maximum at 24 hr, approximately at the time DNA synthesis began. Rates of incorporation of radioactivity from [14-C]acetate into fatty acids and into CO2 by phytohemagglutinin-treated blood were not significantly different from control values. Phytohemagglutinin stimulation of sterol synthesis could be abolished by the addition of certain oxygenated derivatives of cholesterol (e.g., 25-hydroxycholesterol and 20alpha-hydroxycholesterol) which specifically depress the activity of the regulatory enzyme in the sterol synthesis pathway, 3-hydroxy-3-methylglutaryl CoA reductase [mevalonate:NADP-nOXIDOREDUCTASE (CoA acylating); EC 1.1.1.34]. This treatment also abolished DNA synthesis and blastogenesis which otherwise followed the peak of sterol synthesis. Furthermore, DNA synthesis was repressed only if the inhibitor was added early enough to prevent sterol synthesis from reaching its usual maximum. When the compound was added after the rate of sterol synthesis had reached its maximum, DNA synthesis was not affected. These findings suggest that the synthesis of cholesterol is an essential prerequisite for successful initiation and completion of the cell cycle in lymphocytes after phytohemagglutinin activation