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Sugar beet (Beta vulgaris ssp. vulgaris) is an important crop of temperate climates which provides nearly 30% of the world's annual sugar production and is a source for bioethanol and animal feed. The species belongs to the order of Caryophylalles, is diploid with 2n = 18 chromosomes, has an estimated genome size of 714-758 megabases and shares an ancient genome triplication with other eudicot plants. Leafy beets have been cultivated since Roman times, but sugar beet is one of the most recently domesticated crops. It arose in the late eighteenth century when lines accumulating sugar in the storage root were selected from crosses made with chard and fodder beet. Here we present a reference genome sequence for sugar beet as the first non-rosid, non-asterid eudicot genome, advancing comparative genomics and phylogenetic reconstructions. The genome sequence comprises 567 megabases, of which 85% could be assigned to chromosomes. The assembly covers a large proportion of the repetitive sequence content that was estimated to be 63%. We predicted 27,421 protein-coding genes supported by transcript data and annotated them on the basis of sequence homology. Phylogenetic analyses provided evidence for the separation of Caryophyllales before the split of asterids and rosids, and revealed lineage-specific gene family expansions and losses. We sequenced spinach (Spinacia oleracea), another Caryophyllales species, and validated features that separate this clade from rosids and asterids. Intraspecific genomic variation was analysed based on the genome sequences of sea beet (Beta vulgaris ssp. maritima; progenitor of all beet crops) and four additional sugar beet accessions. We identified seven million variant positions in the reference genome, and also large regions of low variability, indicating artificial selection. The sugar beet genome sequence enables the identification of genes affecting agronomically relevant traits, supports molecular breeding and maximizes the plant's potential in energy biotechnology.

AbstractMicrobial carbon (C) use efficiency (CUE) delineates the proportion of organic C used by microorganisms for anabolism and ultimately influences the amount of C sequestered in soils. However, the key factors controlling CUE remain enigmatic, leading to considerable uncertainty in understanding soil C retention and predicting its responses to global change factors. Here, we investigate the global patterns of CUE estimate by stoichiometric modeling in surface soils of natural ecosystems, and examine its associations with temperature, precipitation, plant‐derived C and soil nutrient availability. We found that CUE is determined by the most limiting resource among these four basic environmental resources within specific climate zones (i.e., tropical, temperate, arid, and cold zones). Higher CUE is common in arid and cold zones and corresponds to limitations in temperature, water, and plant‐derived C input, while lower CUE is observed in tropical and temperate zones with widespread limitation of nutrients (e.g., nitrogen or phosphorus) in soil. The contrasting resource limitations among climate zones led to an apparent increase in CUE with increasing latitude. The resource‐specific dependence of CUE implies that soils in high latitudes with arid and cold environments may retain less organic C in the future, as warming and increased precipitation can reduce CUE. In contrast, oligotrophic soils in low latitudes may increase organic C retention, as CUE could be increased with concurrent anthropogenic nutrient inputs. The findings underscore the importance of resource limitations for CUE and suggest asymmetric responses of organic C retention in soils across latitudes to global change factors.

Abstract Radiation damage in biological systems is initiated by free radicals and progresses with time through a variety of mechanisms. The time-scale and details of these mechanisms are briefly reviewed. Because of the variety of mechanisms of radio-biological damage, any single radio-protective or therapeutic agent can be only partially effective. The potential of and need for simultaneously using several radio-protective and therapeutic agents, including sulfhydryl compounds, superoxide dismutase, antioxidant proteins, and DNA repair enzymes, are examined, based on a priori considerations of the consequences of radiation exposure.

In this article is presented the preliminary evaluation of the performance of radiation transmission of glass block, used in support of photovoltaic cells, investigating different internal surface points of the block, which are subject to different shading during daylight hours. The aim is to establish how the edging setting, the only opaque element, can reduce the amount of light radiation during the day, introducing in this way a reduction of efficiency of the entire generation system. The generation system can be based on traditional photovoltaic cells or on the most suitable dye sensitized solar cells. An experimental measurement setup employing a microprocessor-based instrument has been created and a set of measures have been carried out. The measures prove that the shading effect at different irradiation angles do not affect significantly the lighting over the PV cell.

At the International Symposium on Biodegradable Polymers (ISBP2022) in Sion, Switzerland, experts from academia and industry underscored the remarkable progress in biobased and biodegradable polymers (BBPs) since their initial commercialization around 50 years ago. Despite significant advancements, the technology readiness level (TRL), market adoption, and industrialization of BBPs is not yet competitive to conventional plastics. In this perspective, we summarize the challenges and requirements for advancing the development and industrialization of BBPs, drawing insights from international experts coming from academia and industry, who had participated in the survey and podium discussion during the ISBP2022. In fact, BBPs grapple with persistent and emerging challenges throughout the value chain. These challenges can be grouped into four areas and involve i) the pursuit of sustainable feedstocks together with efficient production and downstream processes as well as recycling technologies and infrastructure; ii) meeting or revisiting product requirements by industry, markets, and consumers; iii) navigating a non-level playing field in their sustainability assessment (LCA) compared to conventional plastics; and iv) struggling with underdeveloped and partially biased policy and financial frameworks as well as lacking clear definitions, terminologies and communication.

The fungus gardens of leaf-cutting ants are natural biomass conversion systems that turn fresh plant forage into fungal biomass to feed the farming ants. However, the decomposition potential of the symbiont Leucocoprinus gongylophorus for processing polysaccharides has remained controversial. We therefore used quantifiable DeepSAGE technology to obtain mRNA expression patterns of genes coding for secreted enzymes from top, middle, and bottom sections of a laboratory fungus-garden of Acromyrmex echinatior leaf-cutting ants.A broad spectrum of biomass-conversion-relevant enzyme genes was found to be expressed in situ: cellulases (GH3, GH5, GH6, GH7, AA9 [formerly GH61]), hemicellulases (GH5, GH10, CE1, GH12, GH74), pectinolytic enzymes (CE8, GH28, GH43, PL1, PL3, PL4), glucoamylase (GH15), α-galactosidase (GH27), and various cutinases, esterases, and lipases. In general, expression of these genes reached maximal values in the bottom section of the garden, particularly for an AA9 lytic polysaccharide monooxygenase and for a GH5 (endocellulase), a GH7 (reducing end-acting cellobiohydrolase), and a GH10 (xylanase), all containing a carbohydrate binding module that specifically binds cellulose (CBM1). Although we did not directly quantify enzyme abundance, the profile of expressed cellulase genes indicates that both hydrolytic and oxidative degradation is taking place.The fungal symbiont of Acromyrmex leaf-cutting ants can degrade a large range of plant polymers, but the conversion of cellulose, hemicellulose, and part of the pectin occurs primarily towards the end of the decomposition process, i.e. in the bottom section of the fungus garden. These conversions are likely to provide nutrients for the fungus itself rather than for the ants, whose colony growth and reproductive success are limited by proteins obtained from ingesting fungal gongylidia. These specialized hyphal tips are hardly produced in the bottom section of fungus gardens, consistent with the ants discarding old fungal biomass from this part of the garden. The transcripts that we found suggest that actively growing mycelium in the bottom of gardens helps to maintain an optimal water balance to avoid hyphal disintegration, so the ants can ultimately discard healthy rather than decaying and diseased garden material, and to buffer negative effects of varying availability and quality of substrate across the seasons.