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In the process of grain storage, the use of low-temperature grain storage technology can effectively reduce grain losses during storage and ensure grain quality, which is of great significance for maintaining a stable grain supply. Radiative cooling materials, as a new energy-free cooling technology, achieve cooling by radiating heat in the form of electromagnetic waves into outer space. This approach can address issues associated with traditional cooling methods, such as high energy consumption and high chemical oxygen demand (COD) emissions, offering a green and environmentally friendly new approach to low-temperature grain storage. This paper explained the working principle of polymer-based radiative cooling materials and systematically introduced the composition and selection criteria of polymer-based radiative cooling systems. It also categorized and summarized polymer-based radiative cooling materials according to their structural characteristics. The existing problems with different structured radiative cooling materials, as well as future research directions, were also analyzed. This provides a certain research framework for applying radiative cooling materials to grain storage facilities to achieve low-temperature grain storage.

In recent years, with the implementation of grain safety engineering and high-quality grain engineering, grain storage enterprises have carried out research and application of multiple green grain storage technologies such as air conditioning temperature control, grain cooling temperature control and humidity control, internal circulation moisture and temperature control, controlled atmosphere, and comprehensive pest and mold prevention and control based on different regional climate conditions and the storage variety, storage scale, and enterprises processing. These efforts have effectively improved the level of grain storage safety guarantee in China. The safety of grain storage is closely related to moisture content. High moisture content in the grain may cause mold growth or even hotspots, which can endanger the safety of grain storage. On the other hand, low moisture may affect the quality of food consumption and processing. Thus, it is crucial to establish a scientifically and reasonably determined safe storage moisture content of grain under the premise of ensuring the safety of grain storage. This will effectively promote the “green warehousing improvement action” and help save grain to reduce losses. This paper focused on the research process of grain safe storage of moisture in China after more than a decade of research and expert argumentation, key indicators and detection methods that affect the safe storage of grain moisture have been determined, as well as the criteria for determining the safe storage of grain moisture content, in combination with the actual storage situation at home and abroad. Research on the safe storage of grain moisture content in conventional storage and temperature-controlled storage has been systematically carried out, and the relationships between grain moisture content and temperature have been established. The threshold for safe storage of grain moisture content in the region under the new situation has been proposed, which could provide technological support for the formulation of green grain storage related standards.

Exploring the level of intraspecific diversity in taxa experienced radiation is helpful to understanding speciation and biodiversity assembly. Gentiana section Chondrophyllae sensu lato encompasses more than 180 species and occupies more a half of species in the genus. In this study, we collected samples across the range of three species (Gentiana aristata, G. crassuloides and G. haynaldii) in section Chondrophyllae s.l., and recovered the intra‐species variation by comparing with closely related taxon. Using 25 newly sequenced plastid genomes together with previously published data, we compared structural differences, quantified the variations in plastome size, and measured nucleotide diversity in various regions. Our results showed that the plastome size variation in the three Chondrophyllae species ranged from 285 to 628 bp, and the size variation in LSC, IR and SSC ranged from 236 to 898 bp, 52 to 393 bp and 135 to 356 bp, respectively. Nucleotide diversity of plastome or any of the four regions was much higher than the control species. The average nucleotide diversity in plastomes of the three species ranged from 0.0010 to 0.0023 in protein coding genes, and from 0.0023 to 0.0061 in intergenic regions. More repeat sequence variations were detected within the three Chondrophyllae species than the control species. Various plastid sequence matrixes resulted in different backbone topology in two target species, showed uncertainty in phylogenetic relationship based inference. In conclusion, our results recovered that species of G. section Chondrophyllae s.l. has high intraspecific plastome variation, and provided insights into the radiation in this speciose lineage. [ABSTRACT FROM AUTHOR]

Background and Aims Exploring how species diverge is vital for understanding the drivers of speciation. Factors such as geographical separation and ecological selection, hybridization, polyploidization and shifts in mating system are all major mechanisms of plant speciation, but their contributions to divergence are rarely well understood. Here we test these mechanisms in two plant species, Gentiana lhassica and G. hoae , with the goal of understanding recent allopatric species divergence on the Qinghai–Tibet Plateau (QTP). Methods We performed Bayesian clustering, phylogenetic analysis and estimates of hybridization using 561 302 nuclear genomic single nucleotide polymorphisms (SNPs). We performed redundancy analysis, and identified and annotated species-specific SNPs (ssSNPs) to explore the association between climatic preference and genetic divergence. We also estimated genome sizes using flow cytometry to test for overlooked polyploidy. Key Results Genomic evidence confirms that G. lhassica and G. hoae are closely related but distinct species, while genome size estimates show divergence occurred without polyploidy. Gentiana hoae has significantly higher average F IS values than G. lhassica. Population clustering based on genomic SNPs shows no signature of recent hybridization, but each species is characterized by a distinct history of hybridization with congeners that has shaped genome-wide variation. Gentiana lhassica has captured the chloroplast and experienced introgression with a divergent gentian species, while G. hoae has experienced recurrent hybridization with related taxa. Species distribution modelling suggested range overlap in the Last Interglacial Period, while redundancy analysis showed that precipitation and temperature are the major climatic differences explaining the separation of the species. The species differ by 2993 ssSNPs, with genome annotation showing missense variants in genes involved in stress resistance. Conclusions This study suggests that the distinctiveness of these species on the QTP is driven by a combination of hybridization, geographical isolation, mating system differences and evolution of divergent climatic preferences. [ABSTRACT FROM AUTHOR]

The Qinghai-Tibetan Plateau (QTP) and adjacent areas are centres of diversity for several alpine groups. Although it is known that the QTP acted as a source area for diversification of the alpine genus Gentiana , the evolutionary processes underlying diversity in this genus, especially the formation of narrow endemics, are still poorly understood. Hybridization has been proposed as a driver of plant endemism in the QTP but few cases have been documented with genetic data. Here, we describe a new endemic species in Gentiana section Cruciata as G. hoae sp. nov. and explore its evolutionary history with complete plastid genomes and nuclear ribosomal internal transcribed spacer sequence data. Genetic divergence within G. hoae ~3 million years ago was followed by postglacial expansion on the QTP, suggesting Pleistocene glaciations as a key factor shaping the population history of G. hoae. Furthermore, a mismatch between plastid and nuclear data suggest that G. hoae participated in historical hybridization, while population sequencing show this species continues to hybridize with the co-occurring congener G. straminea in three locations. Our results indicate that hybridization may be a common process in the evolution of Gentiana and may be widespread among recently diverged taxa of the QTP. [ABSTRACT FROM AUTHOR]

Premise of the Study: Microsatellite markers were developed for a medicinal herb, Gentiana lawrencei var. farreri (Gentianaceae), for the future assessment of population genetic structure and potential hybridization events with related taxa. Methods and Results: Using the 454 FLX+ sequencing platform, we obtained 81,717 clean reads with an average length of 291 bp. A total of 3031 primer pairs were designed, and 96 were selected for validation. A set of 20 fluorescently labeled primer pairs was further selected and screened for polymorphisms in three G. lawrencei var. farreri populations and one G. veitchiorum population. Among the four populations, the average number of alleles per locus was 15.2. Finally, a set of 17 unlinked loci were determined to be in Hardy–Weinberg equilibrium after two linked loci were removed. Conclusions: The identified simple sequence repeat markers will be useful for genetic diversity and evolution studies in G. lawrencei var. farreri and related taxa. [ABSTRACT FROM AUTHOR]