Search Results (17)

Hydrogen production from water electrolysis offers a highly promising and sustainable route to solve the energy crisis. However, it is severely limited by the sluggish kinetics of the oxygen evolution reaction (OER) occurring on the anode. Herein, employing carbon dots functionalized with benzene sulfonate groups (BS-CDs) as a distinctive inductor, a Co(OH)₂ catalyst featuring abundant defects was synthesized for an enhanced OER. The highly hydrophilic nature of BS-CDs exerts a significant interfacial induction effect on the growth dynamics of Co(OH)₂, fostering the formation of elevated crystal defects and a substantial quantity of oxygen vacancies. The resulting BS-CDs/Co(OH)₂ catalyst requires an overpotential of only 340 mV to achieve a current density of 10 mA cm⁻² in alkaline media, demonstrating markedly improved OER activity compared to pristine Co(OH)₂ and N-CDs/Co(OH)₂ induced by amine-modified CDs. Furthermore, the structural integrity of the catalyst is maintained, with a current retention rate of 92% observed following a 20 h stability assessment. This work provides a novel approach for developing cost-effective transition metal catalysts that exhibit exceptional catalytic efficiency and excellent stability for the OER. Full article

Persimmon (Diospyros kaki Thunb.) fruit size variation is abundant. Studying the size of the persimmon fruit is helpful in improving its economic value. At present, the regulatory mechanism of persimmon fruit size formation is still unclear. In this study, the mechanism of fruit size formation was investigated through morphological, cytological and transcriptomic analyses, as well as exogenous ethrel and aminoethoxyinylglycine (AVG: ethylene inhibitor) experiments using the large fruit and small fruit of ‘Yaoxianwuhua’. The results showed that stages 3–4 (June 11–June 25) are the crucial morphological period for differentiation of large fruit and small fruit in persimmon. At this crucial morphological period, the cell number in large fruit was significantly more than that in small fruit, indicating that the difference in cell number is the main reason for the differentiation of persimmon fruit size. The difference in cell number was caused by cell division. CNR1, ANT, LAC17 and EB1C, associated with cell division, may be involved in regulating persimmon fruit size. Exogenous ethrel resulted in a decrease in fruit weight, and AVG treatment had the opposite effect. In addition, LAC17 and ERF114 were upregulated after ethrel treatment. These results indicated that high ethylene levels can reduce persimmon fruit size, possibly by inhibiting cell division. This study provides valuable information for understanding the regulation mechanism of persimmon fruit size and lays a foundation for subsequent breeding and artificial regulation of fruit size. Full article

Fruit shape is an important external feature when consumers choose their preferred fruit varieties. Studying persimmon (Diospyros kaki Thunb.) fruit shape is beneficial to increasing its commodity value. However, research on persimmon fruit shape is still in the initial stage. In this study, the mechanism of fruit shape formation was studied by cytological observations, phytohormone assays, and transcriptome analysis using the long fruit and flat fruit produced by ‘Yaoxianwuhua’ hermaphroditic flowers. The results showed that stage 2–3 (June 11–June 25) was the critical period for persimmon fruit shape formation. Persimmon fruit shape is determined by cell number in the transverse direction and cell length in the longitudinal direction. High IAA, GA₄, ZT, and BR levels may promote long fruit formation by promoting cell elongation in the longitudinal direction, and high GA₃ and ABA levels may be more conducive to flat fruit formation by increasing the cell number in the transverse direction and inhibiting cell elongation in the longitudinal direction, respectively. Thirty-two DEGs related to phytohormone biosynthesis and signaling pathways and nine DEGs related to cell division and cell expansion may be involved in the persimmon fruit shape formation process. These results provide valuable information for regulatory mechanism research on persimmon fruit formation. Full article

Ploidy breeding is one of the important approaches for persimmon (Diospyros kaki Thunb.) genetic improvement, and vegetative growth of seedlings is the basis for subsequent fruit development. Therefore, the physiological characteristics and transcriptional differences of seedling growth traits in different ploidy persimmon germplasm were studied in this study, which provided a theoretical basis for fruit evaluation and breeding of new polyploid persimmon varieties. Nonuploid and its full-sib hexaploid seedlings obtained from endosperm culture were used as materials. By observing plant phenotype, leaf tissue section, endogenous hormone content, and transcriptome sequencing, the phenotype and physiological characteristics of different ploidy Persimmon seedlings were compared, as well as the differences in transcription levels. (1) Compared with hexaploid seedlings, the nonuploid were more robust and compact, and the leaves were obviously thicker. The cell size of leaf veins and parenchyma were significantly different between the different ploidy plants. (2) The contents of Salicylic Acid (SA), Jasmonic Acid (JA), gibberellin A1 (GA1), gibberellin A3 (GA3) and Indole-3-acetic acid (IAA) in nonuploid leaves were significantly higher than those in hexaploid leaves, while the contents of cytokinin trans-zeanoside (Tzt) and dihydrozeanoside (DZR), N6-isopentenyladenine (iP) and Jasmonoyl-L-isoleucine (JA-ILE) in nonuploid leaves were significantly lower than those in hexaploid leaves. (3) A total of 5796 differentially expressed genes were identified in nonuploid and hexaploid leaves. These differentially expressed genes were mainly related to photosynthesis, plant-pathogen interaction, etc. Among them, YUCCA genes, GA3ox genes, and IPT genes related to hormone synthesis were significantly differentially expressed in the nonuploid and hexaploid leaves. It is speculated that it may be the key regulatory gene that leads to the difference in IAA, gibberellin (GA), and indolepropionic acid (IPA) levels in the nonuploid and the hexaploid. The growth traits of the new Persimmon germplasms with different ploidy were significantly different. The nonuploid plants were shorter and more compact, and the leaves were larger and thicker. These traits were closely related to the content of endogenous hormones, and the balance of endogenous hormones was affected by gene expression. In addition, based on the biological processes involved in hormones and differentially expressed genes, it is speculated that the nonuploid may be superior to the hexaploid in terms of resistance. Full article

Persimmon fruit has a high nutritional value and significantly varies between pollination-constant astringent (PCA) and pollination-constant non-astringent (PCNA) persimmons. The astringency type affects sugar, flavonoids, and tannin accumulation and is well known in persimmon fruit. However, the impact of the fruit astringency type on ascorbic acid (AsA) accumulation is limited. In this study, typical PCA varieties (‘Huojing’ and ‘Zhongshi5’) and PCNA varieties (‘Yohou’ and ‘Jiro’) of persimmon fruit were sampled at four developing stages (S1–S4) to provide valuable information on AsA content variation in PCA and PCNA persimmon. Persimmon fruit is rich in ascorbic acid; the AsA content of the four varieties ‘Zhongshi5’, ‘Huojing’, ‘Jiro’, and ‘Youhou’ mature fruit reached 104.49, 48.69, 69.69, and 47.48 mg/100 g. Fruit of the same astringency type persimmon showed a similar AsA accumulation pattern. AsA content was significantly higher in PCA than PCNA fruit at S1–S3. The initial KEGG analysis of metabolites showed that galactose metabolism is the major biosynthetic pathway of AsA in persimmon fruit. There were significant differences in galactose pathway-related metabolite content in developing PCA and PCNA fruit, such as Lactose, D-Tagatose, and D-Sorbitol content in PCA being higher than that of PCNA. Combined gene expression and WGCNA analyses showed that the expression of the GME (evm.TU.contig4144.37) gene was higher in PCA-type than in PCNA-type fruit in S1–S3 and exhibited the highest correlation with AsA content (r = 690 **, p < 0.01). Four hub genes, including the DNA methylation gene, methyltransferase gene, F-box, and Actin-like Protein, were identified as potential regulators of the GME gene. These results provide basic information on how astringency types affect AsA accumulation and will provide valuable information for further investigation on AsA content variation in persimmon fruit. Full article

As one of the specific practices of natural resource index trading, the forest ecological bank policy (FEB) is essentially a market-based tool. With the deepening of ecological governance, the FEB policy has also become the main method chosen to solve the economic development problems in ecologically rich “low-lying” areas. However, in the process of implementing the FEB policy, the differences in the demands of various stakeholders were found to have led to a complex game phenomenon, resulting in deviations in policy implementation. This study constructs a multiplayer evolutionary game model between local governments and enterprises of different scales and analyzes the evolutionary stabilization strategy (ESS) in the implementation of the FEB policy. The results show that, under different conditions, there are three stabilization strategies in the evolutionary game system, these correspond to F1 (0, 0, 0), F4 (0, 1, 1), and F5 (1, 0, 0), respectively, the implications are that the strict government role with an active regulatory strategy leads to companies of different sizes refusing to participate (i.e., F5) and the lax government role with a negative regulatory strategy leads to companies of different sizes refusing to participate (i.e., F1) or choosing to participate (i.e., F4). Among them, the strict government role stimulates the companies to participate in the FEB policy through the high intensity of government regulation. In addition, as the policy continues to be implemented, the influence of the strict regulation on the “participation” behavior of the companies decreases. Conversely, the lax government role allows the companies to give full play to their autonomy and obtain higher ecological and environmental benefits. Full article

Persimmon (Diospyros kaki) fruit have significant variation between pollination-constant non-astringent (PCNA) and pollination-constant astringent (PCA) persimmons. The astringency type affects not only the soluble tannin concentration but also the accumulation of individual sugars. Thus, we comprehensively investigate the gene expression and metabolite profiles of individual sugars to resolve the formation of flavor differences in PCNA and PCA persimmon fruit. The results showed that soluble sugar, starch content, sucrose synthase, and sucrose invertase were significantly different between PCNA and PCA persimmon fruit. The sucrose and starch metabolism pathway was considerably enriched, and six sugar metabolites involving this pathway were significantly differentially accumulated. In addition, the expression patterns of diferentially expressed genes (such as bglX, eglC, Cel, TPS, SUS, and TREH genes) were significantly correlated with the content of deferentially accumulated metabolites (such as starch, sucrose, and trehalose) in the sucrose and starch metabolism pathway. These results indicated that the sucrose and starch metabolism pathway maintained a central position of sugar metabolism between PCNA and PCA persimmon fruit. Our results provide a theoretical basis for exploring functional genes related to sugar metabolism and provide useful resources for future studies on the flavor differences between PCNA and PCA persimmon fruit. Full article

Catechins are essential phenolic compounds in persimmon. However, the catechin content in the leaves of persimmon germplasms has not been systematically and comprehensively evaluated. To systematically assess catechin variation in different growth stages and astringency types of persimmon leaves, the young and adult leaves catechin content of 249 persimmon germplasms from Korea, Japan, and 16 provinces in China was quantified using an HPLC method. The results showed that the content of (−)-epicatechin (EC) and (−)-gallocatechin gallate (GCG) had higher coefficient of variation (CV) values in persimmon young leaves (106.74%) and adult leaves (91.49%), respectively. The genetic diversity H’ of (+)-catechin (CA) and (+)-gallocatechin (GC) content was higher in young leaves (2.00 and 2.03), and the H’ value of (−)-epigallocatechin (EGC) and CA content was higher in adult leaves (1.98 and 1.92). The non-galloylated catechins, EGC, EC, and CA, were significantly positively correlated with each other in both young and adult leaves. Catechins of persimmon leaves showed different accumulation patterns in different growth stages and astringency types; (−)-epigallocatechin gallate (EGCG) and CA had the highest average content in the persimmon germplasms of Guangxi and Shanxi provinces of China, respectively. The content of (+)-catechin gallate (CG) was found to be significantly higher in Japanese pollination-constant non-astringent (J-PCNA) persimmon leaves, and EC, GCG had the highest levels in Chinese PCNA (C-PCNA) type. The 249 germplasms were classified into five clusters (Cluster I-V) by SOM clustering based on the content of nine catechins, with EC, CA, and GC having the highest content in Cluster V of the adult leaves. In addition, four excellent germplasms of Cluster III had the highest EGC and GC content in young leaves. Thus, the critical period for catechin utilization of persimmon leaves can be further determined, and provide theoretical references for excellent germplasm screening. Full article

Basic helix–loop–helix (bHLH) proteins belong to one of the largest families involved in plant growth, development, signal transduction, and secondary metabolism. Although bHLH genes have been previously identified in persimmon (Diospyros kaki), systematic studies have not been reported. A total of 59 bHLH family members have been identified from the “Xiaoguotianshi” persimmon transcriptome. These proteins were clustered into 12 groups from I to XII based on their phylogenetic relationships with Arabidopsis thaliana. Combined with the phylogenetic analysis, in silico expression patterns of five developmental stages, the protein–protein interaction analysis between DkbHLH and DkMYB proteins showed that the bHLH_Cluster-15548.1 protein sequence was identified to be highly similar to the AtGL3 (AT5G41315.1) protein, which is associated with flavonoid and proanthocyanidin (PA) biosynthesis. This study presents the systematic analysis of bHLH genes from D. kaki and provides valuable information for further research on the involvement of bHLH protein in anthocyanin biosynthesis. Full article

Persimmon (Diospyros kaki Thunb.) is an economically important tree with a long history of cultivation in China. So far, a total of approximately 1000 varieties have been found in China. To systematically evaluate the diversity of persimmon fruit quality, 22 quality measures of appearance, intrinsic, and sensory quality were evaluated using 61 typical persimmon fruit. According to the findings, the coefficient of variation (CV) of 15 appearance and intrinsic quality index values ranged from 13.81% (fruit shape index) to 165.80% (firmness), and the CV values of 7 intrinsic quality attributes were all higher than 50%, with the CV of total polyphenols and ironic soluble pectin contents (ISP) being as high as 159.82% and 143.80%, respectively. These findings showed that several persimmon germplasm resources had a highly diverse range of fruit quality, wide variation, and distribution. Insoluble tannin and soluble sugar were shown to have a substantial positive correlation with the sensory flavor indexes (p < 0.05), indicating their significance in influencing the flavor quality of persimmon fruit. Cluster analysis was performed utilizing 15 indexes of appearance, intrinsic quality, and 7 indexes of sensory quality. The samples were divided into two groups: group I consisted of 52 pollination−constant and astringent (PCA) and 1 pollination−-variant astringent (PVA) persimmon resources, and group II consisted of 6 pollination−constant non−astringent (PCNA) and 2 pollination−variant non−astringent (PVNA) persimmon resources. The results were consistent with the classification based on the mode of astringency loss, indicating that there was a significant difference in the quality of astringent and non−astringent persimmon fruit. This study provides theoretical references for the development and application of persimmon germplasm resources. Full article

With the intensification of conflicts between different ecosystem services, how to achieve a win-win situation between socio-economic development and ecological protection is an important issue that needs to be addressed nowadays. In particular, how to better quantify and assess the intensity of ecosystem service trade-offs and their relative benefits, and to identify the influencing factors are issues that need to be studied in depth. Based on the INVEST model, this paper analyzed the evolution of spatial and temporal patterns of ecosystem services such as Carbon Storage (CS), Food Production (FP), Habitat Quality (HQ), and Water Yield (WY) in the Shandong Yellow River Basin (SYRB) in 2000, 2010 and 2020. Next, we quantitatively measured the trade-off intensity and revealed the key influencing factors of the trade-off intensity evolution using automatic linear models, root mean square deviation, and geographically weighted regressions. Subsequently, we further analyzed the impact of the correlation between environmental and socio-economic factors on the trade-off intensity of ecosystem services. The results indicated that the temporal and spatial changes of the four main ecosystem services in SYRB area were inconsistent. WY showed a fluctuating trend, with a large interannual gap. CS and FP are on the rise, while HQ is on the decline. Spatially, WY and HQ showed a decreasing distribution from the center to the periphery, while FP and CS showed a decreasing distribution from the southwest to the northeast. The location characteristics of SYRB’s four ecosystem services and their trade-offs were obvious. FP had absolute location advantage in ecosystem service trade-offs. Most of the four ecosystem services showed significant trade-offs, and the trade-off intensity had significant spatial heterogeneity, but the trade-off between FP and CS was relatively weak. At the same time, there were also differences in the trends of trade-off intensities. Counties with low trade-off intensity were mostly located in mountainous areas; these areas are less disturbed by human activities, and most of them are areas without prominent services. Counties with high trade-off intensities were mostly concentrated in areas with relatively developed agriculture; these areas are more disturbed by human activities and are mostly prominent in FP. The trade-off intensity of ecosystem services in SYRB was affected by several factors together, and there were difference characteristics in the degree and direction of influence of each factor. Moreover, these influencing factors have gradually changed over 20 years. In terms of the spatial distribution at the county scale, the influence areas of the dominant drivers of different trade-off types varied greatly, among which the areas with NDVI, CON, and PRE as the dominant factors were the largest. In the future, in effectively balancing regional economic development and ecological environmental protection, quantifiable correspondence strategies should be developed from the administrative perspective of counties and regions based on comprehensive consideration of the locational advantages of each ecosystem service and changes in trade-offs. Full article

To explore the mechanisms of the color formation of different colored persimmon fruits, we used two different colored persimmon cultivars (yellow-peeled persimmon fruit ‘Zhongshi No.6’ and red-peeled persimmon fruit ‘Hongdenglong’) as materials to study the synthesis and accumulation of carotenoids in three stages (full green, color transition, and full yellow or red) using targeted metabolomic and transcriptomic methods. A total of 14 carotenoids and 30 carotenoid lipids were identified in the peel of the two persimmon cultivars. After analysis, it was found that the total carotenoid content of the red persimmon cultivar was higher than that of the yellow persimmon cultivar. The contents of lycopene, α-carotenoid, β-carotenoid, (E/Z)-phytoene, and β-cryptoxanthin are the main reasons for the difference in total carotenoid content between the two persimmon cultivars, especially lycopene. Twelve structural genes involved in the metabolism of carotenoids were also found in this study. In comprehensive metabolome and transcriptome analysis, we found that, between the two persimmon cultivars, lycopene was the key metabolite responsible for the color difference, and PSY, LCYE, and ZDS were the key genes that regulated the differences in lycopene accumulation. The results of this study provide us with new information regarding persimmon fruit synthesis and accumulation. In addition, they also provide a theoretical foundation for improving persimmon fruit germplasm. Full article

Transcription factors are crucial for plant growth and development. MADS-box, WRKY, NAC, and SBP-box, some of the most vital transcription factors, are not well identified in Diospyros spp., and their floral development and sex differentiation related functions remain unknown. We identified and analysed 53 MADS-box, 66 WRKY, 83 NAC, and 17 SBP-box transcription factors using the chromosomal D. oleifera genome. There were six DolSBPs identified as miR156 and miR157 targets. According to the multiple sequence alignments of Arabidopsis and D. oleifera proteins and their conserved domains and motifs, DolMADSs were divided into 23 type I and 30 type II. The DolWRKYs, DolNACs, and DolSBPs were divided into 7, 16, and 6 subgroups, respectively. It was found that one DolMADS, five DolWRKYs, one DolNAC, and four DolSBPs may promote unisexual female flowers development, while three DolMADSs, four DolWRKYs, and one DolNAC may enhance unisexual male flowers development. The functions among the different members of the same family may, thus, vary widely. The results will help to elucidate the evolution of the MADS-box, WRKY, NAC, and SBP-box genes families in D. oleifera and to determine their functions in flower development for Diospyros spp. Full article

In the 2018 Global Environmental Performance Index, China’s global air quality rank was fourth from last, indicating a more pronounced conflict between the environment and development compared with other countries. Because of the vastness of China’s land area, the development of different regions is imbalanced. The achievement of the stipulated goal to be among the top innovative countries in the world by 2035 not only depends on the economically developed eastern part of China but also on the relatively economically underdeveloped central, western, and northeastern parts. In this context, this paper uses time-varying qualitative comparative analysis to explore how the coupling paths of environmental regulation affect regional innovation. The results show that: (1) In most cases at the overall level of China, the Porter hypothesis is supported, and environmental regulation can play the role of a “booster” and stimulate regional innovation. In a few cases, however, the Porter hypothesis is not supported. (2) The Porter hypothesis is also supported in most cases at the regional level, where environmental regulation is mostly a “booster” for regional innovation in the east, center, west, and northeast. (3) Comparison of regional heterogeneity shows that environmental regulation is more important for stimulating regional innovation in the east than in the center, west, and northeast. This study helps to identify the role of environmental regulation in regional innovation. Moreover, it also helps to understand the emphasis China placed on environmental management during the early stages of its economic development. Full article

It is reported that the production of floral sexual phenotype in hexaploid monoecious persimmon (Diospyros kaki) is closely related to a pseudogene called OGI, and a short interspersed nuclear element (SINE)-like insertion (named Kali) in the OGI promoter leads to the gene silence. As a result, DNA methylation level of MeGI promoter determines the development of male or female flowers. However, the molecular mechanism in androecious D. kaki, which only bear male flowers, remains elusive. Here, real-time quantitative polymerase chain reaction (RT-qPCR), molecular cloning, and bisulfite PCR sequencing technique were carried out using 87 materials, including 56 androecious resources, 15 monoecious, and 16 gynoecious cultivars, to investigate the performance of OGI and MeGI on the specific androecious type of D. kaki in China. In conclusion, the Kali insertion was exactly located in the OGI promoter region, and the OGI gene and the Kali sequence were existing and conserved in androecious D. kaki. Meanwhile, we also demonstrated that the MeGI gene was widespread in our investigated samples. Ultimately, our result convincingly provided evidence that the low expression of OGI is probably ascribed to the presence of Kali displaying strong methylation in the OGI promoter, and low expression of MeGI, as well as high DNA methylation level, in the promoter was closely connected with the production of male flowers; this result was consistent with the monoecious persimmon model. Our findings provide predominant genetic aspects for investigation into androecious D. kaki, and future perfecting the sex-determining mechanisms in persimmon. Full article