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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]

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]

Phytophthora sojae causes Phytophthora root and stem rot disease of soybean (Glycine max), leading to huge annual yield loss worldwide, but resistance to Phytophthora sojae (Rps) genes remains elusive. Soybean cultivar "Yudou 29" is resistant to P. sojae strain PsMC1, and this study aimed to clone, identify, and characterize the Rps gene in Yudou 29 (RpsYD29) and clarify its functional mechanism. We map-based cloned RpsYD29 (ZINC FINGER PROTEIN03, GmZFP03) using the families of a cross between Yudou 29 and a P. sojae-susceptible soybean cultivar "Jikedou 2". P. sojae resistance of GmZFP03 was functionally validated by stable soybean genetic transformation and allele-phenotype association analysis. GmZFP03 was identified as a C2H2-type zinc finger protein transcription factor, showing 4 amino acid residue polymorphisms (V79F, G122-, G123-, and D125V) and remarkably different expression patterns between resistant and susceptible soybeans. Notably boosted activity and gene expression of superoxide dismutase (SOD) in resistant-type GmZFP03-expressed transgenic soybean, substantial enhancement of P. sojae resistance of wild-type soybean by exogenous SOD treatment, and GmZFP03 binding to and activation of 2 SOD1 (Glyma.03g242900 and Glyma.19g240400) promoters demonstrated the involvement of SOD1s in GmZFP03-mediated resistance to P. sojae strain PsMC1. Thus, this study cloned the soybean P. sojae-resistant GmZFP03, the product of which specifically targets 2 SOD1 promoters. GmZFP03 can be directly used for precise P. sojae-resistance soybean breeding., Competing Interests: Conflict of interest statement. None declared ., (© The Author(s) 2023. Published by Oxford University Press on behalf of American Society of Plant Biologists.)

Fruits and vegetables in the Cucurbitaceae family contribute greatly to the human diet, for example, cucumber, melon, watermelon and squash. The widespread use of genome editing technologies has greatly accelerated the functional characterization of genes as well as crop improvement. However, most economically important cucurbit plants, including melon and squash, remain recalcitrant to standard Agrobacterium tumefaciens-mediated transformation, which limits the effective use of genome editing technology. In this study, we describe the "optimal infiltration intensity" strategy to establish an efficient genetic transformation system for melon and squash. We harnessed the power of this method to target homologs of the ERECTA family of receptor kinase genes and created alleles resulting in a compact plant architecture with shorter internodes in melon, squash and cucumber. The optimized transformation method presented here allows stable CRISPR/Cas9-mediated mutagenesis and will lay a solid foundation for functional gene manipulation in cucurbit crops., (© The Author(s) 2022. Published by Oxford University Press. All rights reserved.)