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To investigate the impact of relative humidity on the mechanical properties and microscopic pore structure of air lime-stabilized compressed earth, unconfined compression strength (UCS), mercury intrusion porosimetry (MIP) and scanning electron microscopy (SEM) tests were conducted by varying the air lime content and relative humidity (RH) in compressed earth. The results revealed three typical failure modes in unconfined compression strength tests of lime-stabilized compressed earth. Both the unconfined compression strength and characteristic parameters of pore structure in lime-stabilized compressed earth exhibited a trend of initial increase, following by a decrease as the air lime content and relative humidity increased. At the microscopic level, the relative humidity and air lime content interacted with the changes in macro-level unconfined compression strength, and the increase of both could promote the lime hydration reactions, inhibiting the crack development. Considering the influence of relative humidity, mechanical performance, and economic benefit improvement, the recommended air lime content for high humidity and low humidity were 0–28% and 0–26%, respectively, offering valuable insights for the optimization and application of lime-stabilized compressed earth as a modern construction material for structural walls. [ABSTRACT FROM AUTHOR]

In this study, a novel radio‐frequency cold plasma‐assisted extraction (CPAE) process was developed for the extraction of anthocyanins from a type of agricultural biomass waste, purple corncob. The effects of cold plasma pretreatment on anthocyanin extraction were investigated, and this process was further optimized using response surface methodology. The components of purple corncob anthocyanins (PCAs) were analyzed by super‐high performance liquid chromatography‐mass spectrum. The antioxidant activity of PCAs was evaluated through 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) and 2′‐azinobis‐(3‐ethylbenzthiazoline‐6‐sulfonate) (ABTS) scavenging capacity assays in vitro and physiological behaviors in vivo for Caenorhabditis elegans. The results showed that the optimal conditions of cold plasma pretreatment were discharge power 127 W, working pressure 150 Pa, and the treatment time 75 s. The maximum yield of PCAs was about 4.05 ± 0.05 mg/g corncob, much higher than that of the conventional solvent extraction and ultrasonic‐assisted extraction. PCAs were mainly composed of pelargonidin‐3‐galactoside (66.02 wt.%), cyanidin‐3‐galactoside (25.95 wt.%), cyanidin (8.02 wt.%), and petunidin‐3‐galactoside (0.02 wt.%). The extracted anthocyanins reflected the superior antioxidant activity. In terms of in vitro antioxidant ability, the half maximal inhibitory concentration (IC50) of PCAs for DPPH and ABTS were slightly lower than those of ascorbic acid. Meanwhile, C. elegans exhibited positive effects on several physiological behaviors by feeding PCAs, including a 29.25% increase in lifespan, and increases in antioxidant capacity, superoxide dismutase, and catalase (CAT) activity of 26.28%, 28.93%, and 22.24%, respectively. The CPAE process is therefore a highly competitive candidate for the realization of industrial PCAs extraction, combining some additional advantages of cold plasma treatment such as green process, low cost, short treatment time, and scale‐up production. Practical applications: Agricultural biomass wastes (e.g., corncob, straws, and husks) contain a large number of high value‐added natural active ingredients (e.g., polysaccharides, anthocyanins, and polyphenols). However, a highly efficient extraction of these natural active ingredients is always sought, as the protection of lignocellulosic cell walls hinders the extraction of intracellular products. In this work, the cold plasma‐assisted extraction (CPAE) process showed a comparatively higher anthocyanin yield than the conventional solvent extraction and ultrasonic‐assisted extraction processes. This was due to the fact that the high‐energy helium plasma attack readily broke down the lignocellulosic structure of the plant cell walls, resulting in the rapid release of intracellular purple corncob anthocyanins into the extraction medium. This study suggests that the CPAE process will become an emerging application for the industrial extraction of high value‐added natural active ingredients from agricultural biomass wastes. [ABSTRACT FROM AUTHOR]

Cotton (Gossypium spp.) is one of the most important fiber crops worldwide. In the last two decades, transgenesis and genome editing have played important roles in cotton improvement. However, genotype dependence is one of the key bottlenecks in generating transgenic and gene‐edited cotton plants through either particle bombardment or Agrobacterium‐mediated transformation. Here, we developed a shoot apical meristem (SAM) cell‐mediated transformation system (SAMT) that allowed the transformation of recalcitrant cotton genotypes including widely grown upland cotton (Gossypium hirsutum), Sea island cotton (Gossypium barbadense), and Asiatic cotton (Gossypium arboreum). Through SAMT, we successfully introduced two foreign genes, GFP and RUBY, into SAM cells of some recalcitrant cotton genotypes. Within 2–3 months, transgenic adventitious shoots generated from the axillary meristem zone could be recovered and grown into whole cotton plants. The GFP fluorescent signal and betalain accumulation could be observed in various tissues in GFP‐ and RUBY‐positive plants, as well as in their progenies, indicating that the transgenes were stably integrated into the genome and transmitted to the next generation. Furthermore, using SAMT, we successfully generated edited cotton plants with inheritable targeted mutagenesis in the GhPGF and GhRCD1 genes through CRISPR/Cas9‐mediated genome editing. In summary, the established SAMT transformation system here in this study bypasses the embryogenesis process during tissue culture in a conventional transformation procedure and significantly accelerates the generation of transgenic and gene‐edited plants for genetic improvement of recalcitrant cotton varieties. [ABSTRACT FROM AUTHOR]

This paper aims at solving the material durability problem caused by spraying deicing salt on pavement concrete in the northern winter. Super absorbent polymer (SAP) was adopted as an internal curing agent to enhance the durability of pavement concrete. Curing parameters including particle size and dosage of SAP and curing condition were optimized based on mortar tests by means of the grey target decision method. The deterioration rule of durability and mechanical properties of pavement concrete internally cured by different SAP dosages after salt freeze–thaw cycles were explored through rapid freeze–thaw test. Combined with the characteristics of pore structure, hydration and microstructure, the influence mechanism of SAP on the salt freeze–thaw resistance of pavement concrete was revealed. The experimental results showed that: (i) The reduction in mass loss rate and relative dynamic modulus was significantly improved by SAP internal curing with moderate dosage; (ii) The more freeze–thaw cycles the specimen underwent, the greater the increase in strength; (iii) After 75 cycles, the chloride ion erosion depth could be decreased by approximately 23.18%. Moreover, the addition of SAP could refine the pore size, inhibit the generation of shrinkage microcracks, and promote the degree of cement hydration in the late stage, which improved the internal density of the cement concrete structure. Therefore, the deterioration of pavement under the coupling effect of salt freeze–thaw was reduced. [ABSTRACT FROM AUTHOR]

Cold plasma pretreatment has the potential of anti-aging. However, its molecular mechanism is still not clear. Here, cold plasma pretreatment was firstly used to investigate the anti-aging effects of Caenorhabditis elegans using transcriptomic technique. It showed that the optimal parameters of discharge power, processing time, and working pressure for cold plasma pretreatment were separately 100 W, 15 s, and 135 Pa. The released 0.32 mJ/cm2 of the moderate apparent energy density was possibly beneficial to the strong positive interaction between plasma and C. elegans. The longest lifespan (13.67 ± 0.50 for 30 days) was obviously longer than the control (10.37 ± 0.46 for 23 days). Furthermore, compared with the control, frequencies of head thrashes with an increase of 26.01% and 37.31% and those of body bends with an increase of 33.37% and 34.51% on the fourth and eighth day, respectively, indicated movement behavior was improved. In addition, the variation of the enzyme activity of superoxide dismutase (SOD), catalase (CAT), and malondialdehyde (MDA) hinted that the cold plasma pretreatment contributed to the enhanced anti-aging effects in nematodes. Transcriptomics analysis revealed that cold plasma pretreatment resulted in specific gene expression. Anatomical structure morphogenesis, response to stress, regulation of biological quality, phosphate-containing compound metabolic process, and phosphorus metabolic process were the most enriched biological process for GO analysis. Cellular response to heat stress and HSF1-dependent transactivation were the two most enriched KEGG pathways. This work would provide the methodological basis using cold plasma pretreatment and the potential gene modification targets for anti-aging study. [ABSTRACT FROM AUTHOR]

Unilateral cross incompatibility (UCI) occurs between popcorn and dent corn, and represents a critical step towards speciation. It has been reported that ZmGa1P, encoding a pectin methylesterase (PME), is a male determinant of the Ga1 locus. However, the female determinant and the genetic relationship between male and female determinants at this locus are unclear. Here, we report three different types, a total of seven linked genes underlying the Ga1 locus, which control UCI phenotype by independently affecting pollen tube growth in both antagonistic and synergistic manners. These include five pollen-expressed PME genes (ZmGa1Ps-m), a silk-expressed PME gene (ZmPME3), and another silk-expressed gene (ZmPRP3), encoding a pathogenesis-related (PR) proteins. ZmGa1Ps-m confer pollen compatibility. Presence of ZmPME3 causes silk to reject incompatible pollen. ZmPRP3 promotes incompatibility pollen tube growth and thereby breaks the blocking effect of ZmPME3. In addition, evolutionary genomics analyses suggest that the divergence of the Ga1 locus existed before maize domestication and continued during breeding improvement. The knowledge gained here deepen our understanding of the complex regulation of cross incompatibility. Unilateral cross incompatibility (UCI) is a type of prezygotic reproductive isolation, which is associated with multiple loci in maize. Here, the authors use genetic analysis to separate the Ga1 locus into two functional components and identify seven linked genes encoding three types of proteins. [ABSTRACT FROM AUTHOR]

To clarify the influencing mechanism of superabsorbent polymer (SAP) internal curing agent on the carbonation resistance of cement concrete, accelerated carbonation experiment was conducted to explore the effect of particle size and dosage of SAP on carbonation depth. The hydration performance of internally cured concrete at different ages was studied by Fourier transform infrared spectroscopy (FTIR) test and X-ray diffraction (XRD) test. Combined with the scanning electron microscope (SEM) test, the hydration filling effect of internal curing on the microstructure of concrete was analyzed; meanwhile, the influence mechanism of SAP on carbonation resistance was revealed. The results showed that (i) when the particle size and dosage of SAP were 100 mesh and 0.200%, the carbonation depth of internally cured concrete was only 56.5% of the control group on day 28; (ii) the Ca(OH)2 absorption peak area of SAP-concrete in the FTIR spectra could be increased by 3.38 times than that of the control group, and more C2S and C3S were translated into Ca(OH)2, which helped to improve the hydration degree of cement concrete; (iii) the hydration products of day 56 were increased significantly and the remaining pores formed by SAP gels were gradually filled by hydration products, which enhanced the compactness and carbonation resistance of cement concrete. [ABSTRACT FROM AUTHOR]

Summary: Low grain moisture at harvest is crucial for safe production, transport and storage, but the genetic architecture of this trait in maize (Zea mays) remains elusive. Here, we measured the dynamic changes in grain moisture content in an association‐mapping panel of 513 diverse maize inbred lines at five successive stages across five geographical environments. Genome‐wide association study (GWAS) revealed 71 quantitative trait loci (QTLs) that influence grain moisture in maize. Epistatic effects play vital roles in the variability in moisture levels, even outperforming main‐effect QTLs during the early dry‐down stages. Distinct QTL–environment interactions influence the spatio‐temporal variability of maize grain moisture, which is primarily triggered at specific times. By combining genetic population analysis, transcriptomic profiling and gene editing, we identified GRMZM5G805627 and GRMZM2G137211 as candidate genes underlying major QTLs for grain moisture in maize. Our results provide insights into the genetic architecture of dynamic changes in grain moisture, which should facilitate maize breeding. [ABSTRACT FROM AUTHOR]

Summary: The nutritional traits of maize kernels are important for human and animal nutrition, and these traits have undergone selection to meet the diverse nutritional needs of humans. However, our knowledge of the genetic basis of selecting for kernel nutritional traits is limited. Here, we identified both single and epistatic quantitative trait loci (QTLs) that contributed to the differences of oil and carotenoid traits between maize and teosinte. Over half of teosinte alleles of single QTLs increased the values of the detected oil and carotenoid traits. Based on the pleiotropism or linkage information of the identified single QTLs, we constructed a trait–locus network to help clarify the genetic basis of correlations among oil and carotenoid traits. Furthermore, the selection features and evolutionary trajectories of the genes or loci underlying variations in oil and carotenoid traits revealed that these nutritional traits produced diverse selection events during maize domestication and improvement. To illustrate more, a mutator distance–relative transposable element (TE) in intron 1 of DXS2, which encoded a rate‐limiting enzyme in the methylerythritol phosphate pathway, was identified to increase carotenoid biosynthesis by enhancing DXS2 expression. This TE occurs in the grass teosinte, and has been found to have undergone selection during maize domestication and improvement, and is almost fixed in yellow maize. Our findings not only provide important insights into evolutionary changes in nutritional traits, but also highlight the feasibility of reintroducing back into commercial agricultural germplasm those nutritionally important genes hidden in wild relatives. Significance Statement: The identification and selection‐feature characterization of genetic loci contributing to nutritional trait variation between maize and teosinte is of fundamental importance in understanding the evolutionary interface between plant and human. Most favorable alleles associated with nutritional traits exist in teosinte and are not fixed in modern maize, underscoring the potential benefit of introducing teosinte alleles during maize breeding regimens to yield hybrids with desirable nutritional traits. [ABSTRACT FROM AUTHOR]

CRISPR/Cas9, Genome-editing, Fluorescence protein, Visualization, Zea mays Keywords: CRISPR/Cas9; Genome-editing; Fluorescence protein; Visualization; Zea mays EN CRISPR/Cas9 Genome-editing Fluorescence protein Visualization Zea mays 872 874 3 05/20/21 20210501 NES 210501 The emerging and promising biotechnology methodology of CRISPR/Cas9 gene editing is revolutionizing crop improvement. [Extracted from the article]

An AGAMOUS ( AG)-like gene, GbAGL2, was isolated from Gossypium barbadense and characterized. Alignment and phylogenetic analysis indicated that GbAGL2 shared high homology with AG-subfamily genes and belonged to a C-class gene family. DNA gel blot analysis showed that GbAGL2 belonged to a low-copy gene family. Reverse transcriptase-polymerase chain reaction (RT-PCR) and quantitative real-time PCR (qPCR) revealed that GbAGL2 was highly expressed in reproductive tissues including ovules and carpels, but barely expressed in vegetative tissues. In addition, GbAGL2 expression in a cotton cultivar XuZhou142 (wt) (XZ142, G. hirsutum L.) and its fibreless mutant XZ142 (fl) was examined. RNA in situ hybridization analysis indicated that GbAGL2 transcripts were preferentially restricted to outer ovule integuments, carpels and fibres. These expression patterns implied that GbAGL2 might participate in the development of the carpel and ovule. Furthermore, Arabidopsis transformation was performed and modifications occurred in flowers, and the silique length of transgenic plants also increased slightly, suggesting that the GbAGL2 gene may have a positive effect on the development of the ovary or ovule. Our findings suggest that GbAGL2 might not only specify the identity of floral organs but also play a potential key role in ovary or fibre development in cotton. [ABSTRACT FROM AUTHOR]