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Fungi are the prominent phytopathogens that have significant impact on the productivity of agriculture worldwide. Streptomyces species have been extensively studied for the production of various bioactive metabolites. These metabolites have been used as biocontrol agents for the management of diseases caused by phytopathogenic fungi. The purpose of this investigation is to assess the efficacy of Streptomyces sporoverrucosus B-1662, an antagonistic agent in the control of red pepper anthracnose caused by Colletotrichum acutatum KACC 42403 and apple anthracnose caused by Colletotrichum siamense CGCP6 (GYUN-10348). On the basis of the morphological, and molecular characterization using 16S rRNA, the strain B-1662 was determined to be S. sporoverrucosus. The strain B-1662 exhibited antagonistic activity against seven fungal phytopathogens, including C. acutatum KACC 42403 and C. siamense CGCP6. The culture filtrates (CF) from B-1662 showed antifungal activity against all seven fungal pathogens with greater inhibition rate (%) in comparison with a control. The bacterial suspensions of B-1662 showed an excellent biological control effect on the red pepper anthracnose and apple bitter rot using an in planta assay. The anthracnose disease rate (%) was controlled by over 90% with B-1662 cell suspensions at 105 to 107 CFU/mL. Compared to a control, the strain B-1662 played a more effective role in controlling the anthracnose disease in field conditions in both years 2022 and 2023. From the effective solvent fractions, the effect compound (dibutoxybutane) has been isolated exhibiting with antifungal effect. The genetic base underlying the biocontrol traits of B-1662 was characterized using the whole-genome sequence of B-1662, which was compared with closely related strains. Consequently, these results collectively suggest that S. sporoverrucosus B-1662 can aid in the management of red-pepper anthracnose. [ABSTRACT FROM AUTHOR]

Pepper (Capsicum annuum L.) is a popular vegetable in people's daily lives. During pepper growth, calcium (Ca) is an essential macronutrient, and calcium-transporting ATPase (ACA/ECA) is a vital protein for calcium transport. However, reports on the ACA/ECA gene family in the pepper genome are lacking. Hence, we used various bioinformatics methods to identify the ACA/ECA gene family in pepper. We identified eleven CaACA/ECA-family genes in pepper. The chromosomal distribution, phylogenetic evolution, characteristics, gene collinearity, gene and protein structures, cis-acting elements, and specific expression patterns of CaACA/ECAs were analyzed, revealing evolutionary relationships and correlations between CaACA/ECAs and other species (Arabidopsis, rice, and tomato). The experimental results indicate that CaACA/ECAs are stable and hydrophobic proteins, with each of the eleven CaACA/ECA proteins containing all ten motifs. Eleven CaACA/ECA genes are unevenly distributed on the eight chromosomes, and they substantially differ in the number of exons. We found a close correlation between the ACA/ECAs of pepper, Arabidopsis, and tomato. The CaACA/ECA genes contain various plant-hormone-, growth-, and stress-related cis-acting elements. The qRT-PCR results indicate that the expression levels of the eleven CaACA/ECAs exhibit differential temporal expression patterns under various exogenous Ca2+ concentrations. These results provide a theoretical basis for further studying the function of the pepper ACA/ECA gene family and valuable information for identifying and screening genes for pepper stress tolerance breeding. [ABSTRACT FROM AUTHOR]

Fruit colour is a crucial factor influencing both the marketability and quality of pepper (Capsicum annuum), particularly ornamental varieties. Fruit colour is a complex multigenic trait in plant species. Previously, the Arabidopsis pseudo-response regulator 2 (APRR2) gene, one of the regulators that control fruit chlorophyll content and chloroplast development, thereby influencing fruit colour at the green immature stage in tomato (Solanum lycopersicum), cucumber (Cucumis sativus) and pepper, was reported. Functional molecular markers associated with this homologous gene in pepper could be employed to discern fruit colour at the seedling stage, thus improving the efficiency of green/white-fruited pepper breeding. In this study, a derived cleaved amplified polymorphic sequences (dCAPS) marker was developed based on the mutation site in the sequence of a CaAPRR2-like gene that was cloned from the inbred line B1-2, which exhibits milky white fruit at the green immature stage. The marker was subsequently validated in a CaAPRR2-like progeny segregation population. After digestion with the restriction endonuclease TaqI, the amplification product exhibited evident polymorphic bands, enabling it to distinguish between peppers with milky white and green fruit colours. The developed molecular marker displayed remarkable stability and repeatability, thus offering a straightforward and effective tool for enhancing fruit colour in pepper breeding programs. [ABSTRACT FROM AUTHOR]

This study, investigated the concentrations of cadmium, lead and arsenic in vegetables grown with irrigation and sold in Sabon gari and Samaru markets in Zaria, Nigeria. Cadmium was absent in amaranthus, pepper and tomatoes purchased from Samaru market. Nevertheless, amaranthus and lettuce had higher concentrations of these toxic metals than pepper. Total arsenic concentrations in the investigated vegetables were higher than the maximum levels set by the World Health Organization. Total daily intake of the metals was higher than the maximum levels for consuming vegetables from these markets. Therefore, individuals who consume these foods may be at risk. These results indicate the possibility of toxic metal contamination in vegetables purchased from Zaria markets. [ABSTRACT FROM AUTHOR]

Meloidogyne hispanica infects many economically important crops worldwide and has been listed as a quarantine pest in many countries and as an invasive alien species in China. Accurate identification of this pathogen is essential for the establishment of efficient and sustainable integrated pest management programs. During the field investigations in Hainan, China, we discovered galled roots caused by nematode infestation in the pepper field. Further identification of the nematode isolated from the root galls, including morphological and molecular techniques, confirmed that the isolated population infesting the pepper roots belonged to the species M. hispanica. Upon artificial inoculation under greenhouse conditions, the isolated nematodes induced symptoms that closely resembled those observed in the field. To the best of our knowledge, this is the first documented case of M. hispanica parasitizing pepper crops in China, which will provide valuable basis to formulate targeted control strategies. [ABSTRACT FROM AUTHOR]

Due to the vulnerability of pepper (Capsicum spp.) and the virulence of tomato spotted wilt virus (TSWV), seasonal shortages and surges of prices are a challenge and thus threaten household income. Traditional bioassays for detecting TSWV, such as observation for symptoms and reverse transcription-PCR, are time-consuming, labor-intensive, and sometimes lack precision, highlighting the need for a faster and more reliable approach to plant disease assessment. Here, two imaging techniques—Red–Green–Blue (RGB) and hyperspectral imaging (using NDVI and wavelength intensities)—were compared with a bioassay method to study the incidence and severity of TSWV in different pepper accessions. The bioassay results gave TSWV an incidence from 0 to 100% among the accessions, while severity ranged from 0 to 5.68% based on RGB analysis. The normalized difference vegetative index (NDVI) scored from 0.21 to 0.23 for healthy spots on the leaf but from 0.14 to 0.19 for disease spots, depending on the severity of the damage. The peak reflectance of the disease spots on the leaves was identified in the visible light spectrum (430–470 nm) when spectral bands were studied in the broad spectrum (400.93–1004.5 nm). For the selected wavelength in the visible light spectrum, a high reflectance intensity of 340 to 430 was identified for disease areas, but between 270 and 290 for healthy leaves. RGB and hyperspectral imaging techniques can be recommended for precise and accurate detection and quantification of TSWV infection. [ABSTRACT FROM AUTHOR]

Copyright of Science & Technology of Food Industry is the property of Science & Technology of Food Industry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The organic fertilizer (biogas slurry and biogas residues) was produced by the self-developed integrated device of "Pressure swirl / inclined plate sedimentation separation pretreatment (P/I) combined with ultrafiltration / reverse osmosis two stages membrane separation (UF/RO)". The paper focuses on the effect of concentrated biogas slurry and biogas residue produced by this technology on the yield and quality (vitamin C, soluble sugar, protein and nitrate content) of pepper as organic fertilizer compared with chemical fertilizer. The concentrated biogas slurry and biogas residue separated by this technology contained active substances such as N, P, K, trace elements and humic acids with stable composition and potential for good fertilization efficiency. The experiment of seed soaking for pepper sprouting confirmed the best effect of seed soaking with a concentration of 80% biogas slurry. Compared with chemical fertilizer treatment, the application of concentrated biogas slurry and biogas residue can improve the yield and quality of pepper, which is related to the nutrient elements in concentrated digestate. Meanwhile, the results of pepper cultivation trials show that the base fertilizer treatment of biogas residue is best with 2000kg/667m2 and foliar spraying of 75% biogas slurry. The results strongly demonstrate the great potential of the concentrated biogas slurry and biogas residue produced by the self-developed digestate concentration technology for pepper cultivation. [ABSTRACT FROM AUTHOR]

Background: Pepper (Capsicum pubescens), one of five domesticated pepper species, has unique characteristics, such as numerous hairs on the epidermis of its leaves and stems, black seeds, and vibrant purple flowers. To date, no studies have reported on the complete assembly of the mitochondrial genome (mitogenome) of C. pubescens. Understanding the mitogenome is crucial for further research on C. pubescens. Results: In our study, we successfully assembled the first mitogenome of C. pubescens, which was assigned the GenBank accession number OP957066. This mitogenome has a length of 454,165 bp and exhibits the typical circular structure observed in most mitogenomes. We annotated a total of 70 genes, including 35 protein-coding genes (PCGs), 30 tRNA genes, 3 rRNA genes, and 2 pseudogenes. Compared to the other three pepper mitogenomes (KJ865409, KJ865410, and MN196478), C. pubescens OP957066 exhibited four unique PCGs (atp4, atp8, mttB, and rps1), while two PCGs (rpl10 and rps3) were absent. Notably, each of the three pepper mitogenomes from C. annuum (KJ865409, KJ865410, and MN196478) experienced the loss of four PCGs (atp4, atp8, mttB, and rps1). To further explore the evolutionary relationships, we reconstructed a phylogenetic tree using the mitogenomes of C. pubescens and fourteen other species. Structural comparison and synteny analysis of the above four pepper mitogenomes revealed that C. pubescens shares high sequence similarity with KJ865409 and that C. pubescens has rearranged with the other three pepper mitogenomes. Interestingly, we observed 72 similar sequences between the mitochondrial and chloroplast genomes, which accounted for 12.60% of the mitogenome, with a total length of 57,207 bp. These sequences encompassed 12 tRNA genes and the rRNA gene (rrn18). Remarkably, selective pressure analysis suggested that the nad5 gene underwent obvious positive selection. Furthermore, a single-base mutation in three genes (nad1, nad2, and nad4) resulted in an amino acid change. Conclusion: This study provides a high-quality mitogenome of pepper, providing valuable molecular data for future investigations into the exchange of genetic information between pepper organelle genomes. [ABSTRACT FROM AUTHOR]

Fruit color is an important qualitative trait that greatly influences the marketability of peppers. Fruit color can be divided into two categories. Green fruit color denotes commercial maturity, whereas ripe fruit indicates physiological maturity. Herein, segregation populations were created using the 'D24' with pale green in the green fruit stage, orange in the mature fruit stage, and 'D47' with green in the green fruit stage and red in the mature fruit stage. BSA-seq and genetic linkage map analysis revealed green fruit color was linked to (gyqtl1.1) on Chr1 and (gyqtl10.1) on Chr10, while mature fruit color was linked to Chr6. Using functional annotation, sequence, and expression analysis, we speculate that an SNP mutation in the CapGLK2 gene at the gyqtl10.1 interval could initiate premature termination of translation, thus yielding green to pale green fruits in D47. Conversely, the orange color in mature D24 fruits is due to the Indel-mediated premature termination of translation of the CapCCS gene. Our research offers a theoretical foundation for choosing different varieties of pepper fruit based on their color. [ABSTRACT FROM AUTHOR]

Aims The purpose of this study was to explore impacts of different combinations of co-fermentation plant growth-promoting rhizobacteria (PGPR) broth on the growth and yield of pepper. Methods and results The effects of co-fermentation broth containing a random combination of two PGPR strains on the growth of pepper were analyzed. All inoculation treatments promoted growth, yield, and quality of peppers. The relative abundance of the dominant Proteobacteria and Sphingomonas was significantly higher in the planted soil at the seedling and fruiting stages, and the soil available nitrogen, phosphorus, and potassium contents were correspondingly higher. In addition, the co-fermented broth of Bacillus velezensis HP9 and Burkholderia pyrrocinia P10 treatment had the most pronounced effect on plant growth, while the combination of Bacillus flexus HGD12 and P10 had the greatest impact on fruit nutritional indices. This is consistent with the highest enrichment of beneficial bacterial genera at the seedling stage in the HP9 and P10 treatment and at the fruiting stage in the P10 and HGD12 treatment groups, respectively. Conclusions Different combinations of co-fermented bacterial broths increased soil nutrient contents and changed the bacterial community, which in turn promoted the growth, yield, and quality of pepper. [ABSTRACT FROM AUTHOR]

Chili pepper is one of the most widely planted vegetables in China. The current production of fresh chili peppers, such as field management and harvesting, faces the challenges of high labor intensity and low efficiency. The chili pepper industry is ever transitioning towards mechanization and intelligent production. The rapid and accurate detection of chili fruits in the natural environment is of great significance for the automatic picking of chili peppers. However, it is still lacking in the adaptive ability and detection accuracy of the model under different light and occlusion conditions. In this study, an improved detection model, called YOLOX_Pepper, was proposed for chili fruit using YOLOX. Firstly, a fusion-efficient channel CA (coordinate attention) attention mechanism was added to the YOLOX feature fusion network, in order to capture the key features of chili fruits. Secondly, the convolution module in the feature fusion module of the backbone network was replaced with Deformable Convolutional DCNv2 (Deformable ConvNets v2), in order to improve the perceptual ability of the model in the case of the complex geometric features of chili pepper length, width, and aspect ratio, due to branch and fruit occlusion. The experimental results showed that the improved YOLOX_Pepper model had mAP (mean average precision) of 93.30%, which was 3.99, 1.58, 3.19, and 2.84 percentage points higher than that of Faster R-CNN, YOLOv5, YOLOv7, and YOLOX, respectively, with an F1 score of 96%. Under strong light conditions, the mAP of green and red chili fruits of the YOLOX_Pepper model was 69.16% and 89.67%, respectively, and the number of correctly detected green and red peppers was 83 and 304, respectively. Under shadow conditions, the mAP of green and red peppers of the YOLOX_Pepper model was 77.21% and 90.42%, respectively, and the number of green and red peppers was 119 and 255 correctly detected. Under the lack of light conditions, the mAP of the YOLOX_Pepper model for green peppers and red peppers were 77.38% and 75.47%, respectively, and the number of correctly detected green and red peppers were 86 and 311, respectively. The YOLOX_Pepper model performed better in various light conditions, especially in the number and accuracy of detections, compared with the YOLOV5, YOLOV7, and YOLOX models. Under fruit occlusion conditions, the mAP of YOLOX_Pepper was 71.15% and 94.87% for green and red peppers, respectively, and the number of correct detections was 79 and 650 for green and red peppers, respectively. Under branch and foliage occlusion conditions, the mAP of YOLOX_Pepper was 83.98% and 87.10% for green and red peppers, respectively, and the number of correctly detected green and red peppers was 88 and 394, respectively. The improved YOLOX_Pepper model performed better in the chili fruit detection under different occlusions, compared with the YOLOv5, YOLOv7, and YOLOX models. The YOLOX_Pepper model showed excellent performance of detection in complex environments. The effectiveness of the improved module can also provide the intelligent production of chili peppers with reliable technical support. [ABSTRACT FROM AUTHOR]

Key message: A plant growth regulator, 5-aminolevulinic acid, enhanced the saline-alkali tolerance via photosynthetic, oxidative-reduction, and glutathione metabolism pathways in pepper seedlings. Saline-alkali stress is a prominent environmental problem, hindering growth and development of pepper. 5-Aminolevulinic acid (ALA) application effectively improves plant growth status under various abiotic stresses. Here, we evaluated morphological, physiological, and transcriptomic differences in saline-alkali-stressed pepper seedlings after ALA application to explore the impact of ALA on saline-alkali stress. The results indicated that saline-alkali stress inhibited plant growth, decreased biomass and photosynthesis, altered the osmolyte content and antioxidant system, and increased reactive oxygen species (ROS) accumulation and proline content in pepper seedlings. Conversely, the application of exogenous ALA alleviated this damage by increasing the photosynthetic rate, osmolyte content, antioxidant enzyme activity, and antioxidants, including superoxide dismutase, catalase, glutathione reductase, and glutathione peroxidase, and reducing glutathione to reduce ROS accumulation and malonaldehyde content. Moreover, the transcriptomic analysis revealed the differentially expressed genes were mainly associated with photosynthesis, oxidation–reduction process, and glutathione metabolism in saline-alkali stress + ALA treatment compared to saline-alkali treatment. Among them, the change in expression level in CaGST, CaGR, and CaGPX was close to the variation of corresponding enzyme activity. Collectively, our findings revealed the alleviating effect of ALA on saline-alkali stress in pepper seedlings, broadening the application of ALA and providing a feasible strategy for utilize saline-alkali soil. [ABSTRACT FROM AUTHOR]

Globally, salinity is a brutal environmental constraint that poses a major threat to agriculture worldwide, causing nutrient imbalances and oxidative stress, leading to reduced crop yields and quality. Date palm waste from the agro-industry is a major environmental problem, but its conversion to biochar for soil amendment could help alleviate the effects of salinity stress. Pepper is a commonly grown horticultural crop that is sensitive to salinity. That's why the current experiment was conducted with the novel idea of exploring the potential use of biochar-based fertilizer derived from date palm waste as a mitigation strategy for salinity-related problems in pepper. The study was conducted as a pot experiment in a growth chamber under controlled conditions. The experiment consisted of four treatment groups: Control (no salinity stress); BM350E (biochar application only); NaCl (salinity stress without biochar application); BM350E+NaCl (combined biochar and salinity stress application). The soil was amended with biochar at a concentration of 3 g kg−1soil and pepper seedlings were exposed to salinity stress with 150 mM NaCl for seven days. The morphological, biochemical, and physiological responses were then evaluated. The use of BM350E biochar significantly improved plant growth under saline conditions, increasing shoot fresh weight by 9.41%, root fresh weight by 15.32%, shoot length by 5.22%, and root length by 12.57%. It also increased chlorophyll a (Chl. a) by 8.28%, chlorophyll b (Chl. b) by 80.20%, and carotenoids (Car) by 52.43% while increasing antioxidant enzyme activities. In conclusion, BM350E biochar has the potential to effectively mitigate the negative effects of salinity on pepper growth. [ABSTRACT FROM AUTHOR]

The root-knot nematode Meloidogyne enterolobii is a major constraint to pepper production in tropical regions. In the long-term practice of root-knot nematode management, bacterial nematicides have attracted increasing attention as effective biocontrol agents. In this study, we evaluated the efficacy of Bacillus thuringiensis strain 00-50-5 (Bt 00-50-5) against M. enterolobii through in vitro, greenhouse and field trials. The cell-free supernatant of Bt 00-50-5 exhibited potent nematicidal activity against second-stage juveniles (J2s) of M. enterolobii, with mortality rates of 98.0% and 100% after 24 h and 36 h of exposure, respectively. In addition, Bt 00-50-5 showed inhibitory effects on the hatching of M. enterolobii eggs, resulting in a remarkable 96.6% reduction in the egg hatching rate after 6 days compared to the control. The pot trials showed that both pepper root galls and egg masses were reduced, and plant growth was improved after treatment with Bt 00-50-5. The field trials showed that the gall index was significantly reduced, with a 66.3% and 68.2% reduction in disease index in 2020–2021 and 2021–2022, respectively, and pepper yield was improved, with a 96.2% and 93.1% increase in yield in 2020–2021 and 2021–2022, respectively, compared to the control. These results indicate the potential use of Bt 00-50-5 as an effective biocontrol agent against M. enterolobii. [ABSTRACT FROM AUTHOR]

Pepper (Capsicum annuum) is a globally important vegetable, and Verticillium wilt is an important disease affecting peppers and is caused by Verticillium dahliae, which can severely reduce yields. However, the molecular mechanisms underlying the responses of pepper to infection by V. dahliae are largely unknown. We performed physiological and transcriptome analysis using resistant and susceptible pepper cultivars inoculated with V. dahliae. Compared to the susceptible cultivar MS66, the resistant cultivar MS72 retained higher chlorophyll content and lower malondialdehyde content after inoculation. At 3 days after inoculation (DAI), compared with MS66, 534 differentially expressed genes (DEGs) were identified in MS72. At 5 DAI, 2392 DEGs were identified in MS72 compared with MS66. The DEGs in MS72 were mainly enriched in the cell wall and photosynthesis-related Gene Ontology terms, as well as in pathways such as cutin, suberin, wax biosynthesis, phenylpropanoid biosynthesis, and photosynthesis. Using weighted gene co-expression network analysis, 36 hub genes involved in the resistance response were identified, including the transcription factor bHLH93 (Capana04g000815), defense-like protein 1 (MSTRG.5904), and miraculin-like (Capana10g002167). Our findings contribute to a more comprehensive understanding of the response mechanism of pepper to V. dahliae inoculation, providing new avenues for improving pepper resistance through breeding programs. [ABSTRACT FROM AUTHOR]

Copyright of China Condiment is the property of China Condiment and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Agriculturae Zhejiangensis is the property of Acta Agriculturae Zhejiangensis Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Salt stress is a major abiotic factor that negatively impacts the growth, performance, and secondary metabolite production in pepper (Capsicum annuum L.) plants. Brassinosteroids (BRs) play a crucial role in enhancing plant tolerance to abiotic stress, yet their potential in mitigating salt stress in pepper plants, particularly by promoting sugar and glycine betaine accumulation, remains underexplored. In this study, we investigated the effects of the foliar application of 2,4-epibrassinolide (EBR) on salt-stressed pepper seedlings. Our findings revealed that EBR treatment significantly increased the levels of proline, sugar, and glycine betaine under salt stress compared to untreated controls. Moreover, EBR enhanced the antioxidant defense mechanisms in pepper seedlings by increasing sugar and glycine betaine levels, which contributed to the reduction of reactive oxygen species (ROS) and malondialdehyde (MDA) accumulation. [ABSTRACT FROM AUTHOR]

Abiotic stress is one of the key factors harming global agriculture today, seriously affecting the growth and yield of vegetables. Pepper is the most widely grown vegetable in the world, with both high nutritional and economic values. Currently, the increase in global extreme weather events has heightened the frequency of abiotic stresses, such as drought, high and low temperatures, waterlogging, and high salt levels, which impairs pepper growth and development, leading to its reduced yield and quality. In this review, we summarize the research progress on the responses of pepper to abiotic stress in recent years in terms of physiology, biochemistry, molecular level, and mitigation measures. We then explore the existing problems and propose future research directions. This work provides a reference for the cultivation and development of new pepper varieties resistant to abiotic stress. [ABSTRACT FROM AUTHOR]

Temperature is an important limiting factor in the counter-seasonal cultivation of pepper. Currently, there are no studies on transcriptomic analysis of 'cold stress memory' in pepper. In this study, in order to understand the mechanism of 'cold stress memory' in pepper (Capsicum annuum L.), seedlings were subjected to the following treatments: normal temperature treatment (P0), the first cold treatment for 3 days (P3), the recovery temperature treatment for 3 days (R3), and another cold treatment for 3 days (RP3). The results showed that P3 plants wilted the most, RP3 the second and R3 the least. Leaf reactive oxygen species (ROS) and electrolyte leakage were the most in P3, the second in RP3 and the least in R3. In addition, RP3 had the highest accumulation of zeaxanthin, violaxanthin and β-cryptoxanthin, followed by P3, and R3 had the least. These results suggest that pepper seedlings are characterized by 'cold stress memory'. Transcriptomics was used to analyze the key genes and transcription factors involved in the biosynthesis of zeaxanthin, violaxanthin and β-cryptoxanthin during the formation of 'cold stress memory'. This study provides candidate genes and transcription factors for an in-depth study of the cold tolerance mechanism in pepper. [ABSTRACT FROM AUTHOR]

Chloroisobromine cyanuric acid is a highly effective broad-spectrum systemic fungicide for disease control in agricultural crops. In this study, the degradation, residue levels, and potential dietary risks associated with the chloroisobromine cyanuric acid residues in two widely consumed crops, pepper and ginger, were evaluated through supervised field experiments conducted at 12 sites for pepper and 4 sites for ginger in China in 2021. A QuEChERS-LC-MS/MS method was established for quantifying cyanuric acid (CYA) in both crops. The method achieved a limit of quantification (LOQ) of 0.02 mg kg−1 for ginger and 0.05 mg kg−1 for pepper, with recovery rates ranging from 91% to 96% for ginger and 84% to 89% for pepper and the relative standard deviation of 2.9% to 11.2% for ginger and 2.8%~12.9% for pepper, respectively. The results indicated that CYA had half-lives ranging from 3.1 to 8.2 days in pepper, and the terminal CYA residues at harvest were all lower than 5 mg kg−1, the maximum residue limit established in China. Furthermore, the chronic dietary risk exposure to chloroisobromine cyanuric acid in ginger and pepper, harvested at a pre-harvest interval of three days and at the normal harvesting time after the application of 50% chloroisobromine cyanuric acid soluble powder (SP), was 37.96%, which was much lower than 100%, indicating no significant health risks to the Chinese population. This study provides basic data for establishing the MRLs and serving as a reference for developing the analytical method applicable to CYA residues in different plant matrices. [ABSTRACT FROM AUTHOR]

Pepper is a globally cultivated vegetable known for its distinct pungent flavor, which is derived from the presence of capsaicinoids, a class of unique secondary metabolites that accumulate specifically in pepper fruits. Since the accumulation of capsaicinoids is influenced by various factors, it is imperative to comprehend the metabolic regulatory mechanisms governing capsaicinoids production. This review offers a thorough examination of the factors that govern the metabolism of capsaicinoids in pepper fruit, with a specific focus on three primary facets: (1) the impact of genotype and developmental stage on capsaicinoids metabolism, (2) the influence of environmental factors on capsaicinoids metabolism, and (3) exogenous substances like methyl jasmonate, chlorophenoxyacetic acid, gibberellic acid, and salicylic acid regulate capsaicinoid metabolism. The findings of this study are expected to enhance comprehension of capsaicinoids metabolism and aid in the improvement of breeding and cultivation practices for high-quality pepper in the future. [ABSTRACT FROM AUTHOR]

In the environmental context of Türkiye, the quantity of organic matter present in the soil is a crucial factor that affects its productivity potential. While peat offers an optimal growth condition, it is an expensive material due to its limited availability globally, and in Türkiye. Hence, the research employed compost, which could be a viable replacement for peat, and is a sustainable, and independent alternative resource. The study examined the effects of 13 diverse growing media, both in pure, and mixed form, which included a control treatment of a 2:1 peat to perlite mixture, and three composts derived from grape, apple, and tomato pulps. The research investigated various growth criteria, such as seedling height, hypocotyl length, and diameter, number of leaves per seedling, root length, seedling dry weight, and root dry weight of tomato, cucumber, and pepper plants. The study indicated that grape compost, apple compost, tomato compost:peat:perlite (GAT:P:P), and grape compost:peat:perlite (G:P:P) were viable alternatives to the traditional peat/perlite mixture for tomato seedlings. Similarly, grape compost (G), apple compost (A), and apple compost:perlite (A:P) showed potential as substitutes for cucumber seedlings while apple compost (A) proved a possible option for chilli seedlings. In particular, the treatments using solely apple or grape composts, or a combination of both, exhibited superior performance in comparison to the control treatment. [ABSTRACT FROM AUTHOR]

Bacterial leaf spot of pepper (BSP), primarily caused by Xanthomonas euvesicatoria (Xe), poses a significant challenge to pepper production worldwide. Despite its impact, the genetic diversity of this pathogen remains underexplored, which limits our understanding of its population structure. To bridge this knowledge gap, we conducted a comprehensive analysis using 103 Xe strains isolated from pepper in southwest Florida to characterize genomic and type III effector (T3E) variation in this population. Phylogenetic analysis of core genomes revealed a major distinct genetic lineage associated with amylolytic activity. This amylolytic lineage was represented in Xe strains globally. Molecular clock analysis dated the emergence of amylolytic strains in Xe to around 1972. Notably, non-amylolytic strains possessed a single base pair frameshift deletion in the amylase gene yet retained a conserved C-terminus. GUS assay revealed the expression of two open reading frames in non-amylolytic strains, one at the N-terminus and another that starts 136 base pairs upstream of the amylase gene. Analysis of T3Es in the Florida Xe population identified variation in 12 effectors, including two classes of mutations in avrBs2 that prevent AvrBs2 from triggering a hypersensitive response in Bs2-resistant pepper plants. Knowledge of T3E variation could be used for effector-targeted disease management. This study revealed previously undescribed population structure in this economically important pathogen. IMPORTANCE Bacterial leaf spot (BSP), a significant threat to pepper production globally, is primarily caused by Xanthomonas euvesicatoria (Xe). Limited genomic data has hindered detailed studies on its population diversity. This study analyzed the whole-genome sequences of 103 Xe strains from peppers in southwest Florida, along with additional global strains, to explore the pathogen's diversity. The study revealed two major distinct genetic groups based on their amylolytic activity, the ability to break down starch, with non-amylolytic strains having a mutation in the amylase gene. Additionally, two classes of mutations in the avrBs2 gene were found, leading to susceptibility in pepper plants with the Bs2 resistance gene, a commercially available resistance gene for BSP. These findings highlight the need to forecast the emergence of such strains, identify genetic factors for innovative disease management, and understand how this pathogen evolves and spreads. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Shenyang Agricultural University is the property of Journal of Shenyang Agricultural University Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Agriculturae Zhejiangensis is the property of Acta Agriculturae Zhejiangensis Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Agriculturae Zhejiangensis is the property of Acta Agriculturae Zhejiangensis Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Low temperature combined with low light (LL) is an important factor limiting pepper quality and yield. 'Hang Jiao No. 2′ were used as experimental materials, and different concentrations of MeJA (T1 (0 μM), T2 (100 μM), T3 (150 μM), T4 (200 μM), T5 (250 μM) and T6 (300 μM)) were sprayed under LL stress to explore the positive effect of exogenous methyl jasmonate (MeJA) on peppers under LL stress. The photosynthetic properties, osmoregulatory substance, reactive oxygen species, antioxidant enzyme activities, and related gene expressions of the peppers were measured. Our results demonstrated that 200 μM MeJA treatment significantly increased chlorophyll content, light quantum flux per active RC electron transfer (Eto/RC), maximum captured photonic flux per active RC (TRo/RC), energy flux for electron transfer in the excitation cross section (Eto/CSm), energy flux captured by absorption in the excitation cross section (TRo/CSm), soluble protein, and soluble sugar content. Moreover, it significantly improved the maximum photochemical efficiency of PSII (Fv/Fm) and performance index based on absorbed light energy (PI (abs)) by 56.77% and 67.00%, respectively, and significantly decreased malondialdehyde (MDA) content and relative conductivity by 30.55% and 28.17%, respectively. Additionally, antioxidant enzyme activities were elevated, and the expression of the related genes was activated in pepper seedlings under stress, leading to a significant reduction in reactive oxygen species content. In conclusion, our findings confirmed that 200 μM MeJA could reduce the injury of LL to pepper leaves to the photosynthetic organs of pepper leaves, protect the integrity of the cell membrane, and further improve the tolerance of pepper seedlings to LL. [ABSTRACT FROM AUTHOR]

To investigate the variation in pepper quality across different regions, three pepper varieties (Jiao yang 6, La yan 101 and Zhuo jiao xin 52) were selected and planted in Guizhou, Yunnan, Chongqing, Shaanxi and Xinjian Provinces. In order to provide reference for the selection of pepper varieties in different regions, principal component analysis and cluster analysis were employed to evaluate the suitability of each pepper variety for its region by determining the peppers' nutritional quality, such as capsaicin, reducing sugar, amino acids, crude fibre, crude fat, capsaicin. The study revealed that significant variations presented in pepper quality across different producing areas and the coefficient of variation ranged from 5.79% to 50.29%. Among them, capsaicin content varied the most with origin. Notably, the average coefficient of variation was 41.94% for capsaicin and was about 8% for crude fiber and amino acids. The comprehensive evaluation of La yan 101 variety was the highest, then Zhuo jiao xin 52 was the second by principal component analysis. Meanwhile, all three varieties showed higher quality scores when planted in Guizhou Province compared to other four regions. In summary, peppers quality varied significantly among different regions and La yan 101 planted in Guizhou demonstrated the best quality performance. Thus we concluded that these peppers planted in Guizhou Province had quality advantages to other four provinces.

Abstract Background Pepper (Capsicum pubescens), one of five domesticated pepper species, has unique characteristics, such as numerous hairs on the epidermis of its leaves and stems, black seeds, and vibrant purple flowers. To date, no studies have reported on the complete assembly of the mitochondrial genome (mitogenome) of C. pubescens. Understanding the mitogenome is crucial for further research on C. pubescens. Results In our study, we successfully assembled the first mitogenome of C. pubescens, which was assigned the GenBank accession number OP957066. This mitogenome has a length of 454,165 bp and exhibits the typical circular structure observed in most mitogenomes. We annotated a total of 70 genes, including 35 protein-coding genes (PCGs), 30 tRNA genes, 3 rRNA genes, and 2 pseudogenes. Compared to the other three pepper mitogenomes (KJ865409, KJ865410, and MN196478), C. pubescens OP957066 exhibited four unique PCGs (atp4, atp8, mttB, and rps1), while two PCGs (rpl10 and rps3) were absent. Notably, each of the three pepper mitogenomes from C. annuum (KJ865409, KJ865410, and MN196478) experienced the loss of four PCGs (atp4, atp8, mttB, and rps1). To further explore the evolutionary relationships, we reconstructed a phylogenetic tree using the mitogenomes of C. pubescens and fourteen other species. Structural comparison and synteny analysis of the above four pepper mitogenomes revealed that C. pubescens shares high sequence similarity with KJ865409 and that C. pubescens has rearranged with the other three pepper mitogenomes. Interestingly, we observed 72 similar sequences between the mitochondrial and chloroplast genomes, which accounted for 12.60% of the mitogenome, with a total length of 57,207 bp. These sequences encompassed 12 tRNA genes and the rRNA gene (rrn18). Remarkably, selective pressure analysis suggested that the nad5 gene underwent obvious positive selection. Furthermore, a single-base mutation in three genes (nad1, nad2, and nad4) resulted in an amino acid change. Conclusion This study provides a high-quality mitogenome of pepper, providing valuable molecular data for future investigations into the exchange of genetic information between pepper organelle genomes.

In the environmental context of Türkiye, the quantity of organic matter present in the soil is a crucial factor that affects its productivity potential. While peat offers an optimal growth condition, it is an expensive material due to its limited availability globally, and in Türkiye. Hence, the research employed compost, which could be a viable replacement for peat, and is a sustainable, and independent alternative resource. The study examined the effects of 13 diverse growing media, both in pure, and mixed form, which included a control treatment of a 2:1 peat to perlite mixture, and three composts derived from grape, apple, and tomato pulps. The research investigated various growth criteria, such as seedling height, hypocotyl length, and diameter, number of leaves per seedling, root length, seedling dry weight, and root dry weight of tomato, cucumber, and pepper plants. The study indicated that grape compost, apple compost, tomato compost:peat:perlite (GAT:P:P), and grape compost:peat:perlite (G:P:P) were viable alternatives to the traditional peat/perlite mixture for tomato seedlings. Similarly, grape compost (G), apple compost (A), and apple compost:perlite (A:P) showed potential as substitutes for cucumber seedlings while apple compost (A) proved a possible option for chilli seedlings. In particular, the treatments using solely apple or grape composts, or a combination of both, exhibited superior performance in comparison to the control treatment.

Abstract Temperature is an important limiting factor in the counter-seasonal cultivation of pepper. Currently, there are no studies on transcriptomic analysis of ‘cold stress memory’ in pepper. In this study, in order to understand the mechanism of ‘cold stress memory’ in pepper (Capsicum annuum L.), seedlings were subjected to the following treatments: normal temperature treatment (P0), the first cold treatment for 3 days (P3), the recovery temperature treatment for 3 days (R3), and another cold treatment for 3 days (RP3). The results showed that P3 plants wilted the most, RP3 the second and R3 the least. Leaf reactive oxygen species (ROS) and electrolyte leakage were the most in P3, the second in RP3 and the least in R3. In addition, RP3 had the highest accumulation of zeaxanthin, violaxanthin and β-cryptoxanthin, followed by P3, and R3 had the least. These results suggest that pepper seedlings are characterized by ‘cold stress memory’. Transcriptomics was used to analyze the key genes and transcription factors involved in the biosynthesis of zeaxanthin, violaxanthin and β-cryptoxanthin during the formation of ‘cold stress memory’. This study provides candidate genes and transcription factors for an in-depth study of the cold tolerance mechanism in pepper.

Abstract [Objective] PEX (pollen extensin-like) gene is involved in controlling pollen development, which plays a crucial role in embryogenesis of pollen microspores and haploid culture. In this study, the authors isolated the CaPEX3 gene from pepper and analyzed its protein structure and expression pattern, which provides a theoretical foundation for further investigation into the function of the CaPEX3 gene. [Methods] CaPEX3 was cloned by PCR, and its protein structure, evolution, and gene regulation were analyzed by bioinformatics. Expression of CaPEX3 in different tissues and pollen of different varieties were detected by qRT-PCR. Pollen viability of different pepper varieties was detected by staining method and their relationship with CaPEX3 expression was analyzed. [Results] The coding region of CaPEX3 was 1 581 bp in length, encoding 526 amino acids, which belongs to the LRX (leucine-rich repeats/extensins) gene family. The protein had phosphorylation and glycosylation sites, signaling peptides, and transmembrane domains. The expression level of CaPEX3 was the highest in flowers, and the gene expression was higher in tissues with high pollen vitality. The regulatory network predicted that CaPEX3 might be involved in the regulation of pollen development through the action of genes related to flower development. [Conclusion] CaPEX3 was specifically expressed in flowers, and a correlation was observed between its expression level and the activity of pollen grains. The analysis of gene expression and the construction of related vectors provided a theoretical foundation and technical support for the subsequent investigation of gene function and mechanism of CaPEX3

The effectiveness of agroecological management strategies (AEMS) in controlling bacterial wilt caused by Ralstonia solanacearum species complex (RSSC) remains a critical question. A quantitative review was conducted based on publications reporting agroecological bacterial wilt management practices under on‐station or on‐farm field conditions in electronic libraries, without geographical restrictions, on tomato, pepper, eggplant and potato. After applying inclusion and exclusion criteria, 48 papers were retained, resulting in 644 and 146 observations of bacterial wilt incidence (BWI) and yield, respectively. The effectiveness of AEMS for each crop was evaluated based on BWI and crop yield. The effect size was calculated as the natural logarithm of the response ratio, and confidence intervals were determined by bootstrapping. Varietal control, biological control (used of biological control agents) and combinations of many AEMS were the most reported practices, both under on‐station and on‐farm conditions. The use of plant extracts (Thymus spp., Crotalaria spp.), grafting, solarization, soil amendments (manure, compost) and crop rotations (with maize, beans) were also reported. All AEMS significantly reduced bacterial wilt incidence and increased yields compared to the untreated plots. Grafting, combinations of control methods, varietal control and biological control were the most effective agroecological practices in reducing BWI and increasing yield in tomato and eggplant. Varietal control was the most effective compared to biological control on pepper. The effectiveness of AEMS also varied with crop susceptibility and origin, climatic zone and soil acidity. This study highlights the potential of AEMS in reducing BWI and increasing crop yield in infested soils. [ABSTRACT FROM AUTHOR]

Main conclusion: Phosphatidylinositol 4-phosphate 5-kinase gene CaPIP5K4-1 is highly expressed in the pepper anthers. Virus-induced gene silencing of CaPIP5K4-1 leads to reduced male fertility in pepper. The phosphatidylinositol 4-phosphate 5-kinase (PIP5K) is a pivotal enzyme in the phosphatidylinositol signaling pathway, and its crucial involvement in both plant development and stress response has been established. Here, we found that the expression of CaPIP5K4-1 in pepper was significantly higher in the fertile flower buds compared to sterile flower buds. Furthermore, its expression was validated in anthers and pollens by qRT-PCR and RNA-ISH assays, respectively. Its GFP fusion protein was mainly located on the plasma membrane. Silencing CaPIP5K4-1 in fertile pepper accessions resulted in wrinkled pollen grain cell walls, decreased pollen germination efficiency, and inhibited pollen tube growth. The transcription levels of multiple genes in the phosphatidylinositol signaling pathway were also assessed. Five phospholipase C (PLC) genes were downregulated in silenced plants. On the contrary, inositol phosphatase SAC and phosphatase and tensin homolog (PTEN) were upregulated. This study reported the role of CaPIP5K4-1 in pepper male fertility and provided insights into the regulatory mechanisms of PI signaling in pepper. [ABSTRACT FROM AUTHOR]

Abstract Background The growth and yield of pepper, a typical temperature-loving vegetable, are limited by low-temperature environments. Using low-temperature sensitive ‘Hangjiao No. 4’ (Capsicum annuum L.) as experimental material, this study analyzed the changes in plant growth and photosynthesis under different treatments: normal control (NT), low-temperature stress alone (LT), low-temperature stress in strigolactone pretreated plants (SL_LT), and low-temperature stress in strigolactone biosynthesis inhibitor pretreated plants (Tis_LT). Results SL pretreatment increased the net photosynthetic rate (Pn) and PSII actual photochemical efficiency (φPSII), reducing the inhibition of LT on the growth of pepper by 17.44% (dry weight of shoot). Due to promoting the accumulation of carotenoids, such as lutein, and the de-epoxidation of the xanthophyll cycle [(Z + A)/(Z + A + V)] by strigolactone after long-term low-temperature stress (120 h), non-photochemical quenching (NPQ) of pepper was increased to reduce the excess excitation energy [(1-qP)/NPQ] and the photoinhibition degree (Fv/Fm) of pepper seedlings under long-term low-temperature stress was alleviated. Twelve cDNA libraries were constructed from pepper leaves by transcriptome sequencing. There were 8776 differentially expressed genes (DEGs), including 4473 (51.0%) upregulated and 4303 (49.0%) downregulated genes. Gene ontology pathway annotation showed that based on LT, the DEGs of SL_LT and Tis_LT were significantly enriched in the cellular component, which is mainly related to the photosystem and thylakoids. Further analysis of the porphyrin and chlorophyll biosynthesis, carotenoid biosynthesis, photosynthesis-antenna protein, and photosynthetic metabolic pathways and the Calvin cycle under low-temperature stress highlighted 18, 15, 21, 29, and 31 DEGs for further study, which were almost all highly expressed under SL_LT treatment and moderately expressed under LT treatment, whereas Tis_LT showed low expression. Conclusion The positive regulatory effect of SLs on the low-temperature tolerance of pepper seedlings was confirmed. This study provided new insights for the development of temperature-tolerant pepper lines through breeding programs.

To address growing concerns about sustainable agriculture and waste management, this study aimed to explore the viability of tea waste as an eco-friendly alternative substrate for cultivating Charleston peppers (Capsicum annuum), with the goal of optimizing plant growth and yield while reducing soil dependence, lowering cultivation costs, and repurposing agro-industrial waste. Six different substrate combinations were evaluated: 1) Tea waste, 2) Tea waste + Manure, 3) Tea waste + Soil, 4) Manure + Soil, 5) Tea waste + Manure + Soil, and 6) Tea waste + Manure + Soil + Perlite. Data were analyzed using both multivariate and univariate analyses to assess significant differences among treatments. Notably, significant differences in stem diameter were observed among plants grown on different substrates (one-way MANOVA, p

Abstract Background The WD40 domain, one of the most abundant in eukaryotic genomes, is widely involved in plant growth and development, secondary metabolic biosynthesis, and mediating responses to biotic and abiotic stresses. WD40 repeat (WD40) protein has been systematically studied in several model plants but has not been reported in the Capsicum annuum (pepper) genome. Results Herein, 269, 237, and 257 CaWD40 genes were identified in the Zunla, CM334, and Zhangshugang genomes, respectively. CaWD40 sequences from the Zunla genome were selected for subsequent analysis, including chromosomal localization, phylogenetic relationships, sequence characteristics, motif compositions, and expression profiling. CaWD40 proteins were unevenly distributed on 12 chromosomes, encompassing 19 tandem duplicate gene pairs. The 269 CaWD40s were divided into six main branches (A to F) with 17 different types of domain distribution. The CaWD40 gene family exhibited diverse expression patterns, and several genes were specifically expressed in flowers and seeds. Yeast two-hybrid (Y2H) and dual-luciferase assay indicated that CaWD40-91 could interact with CaAN1 and CaDYT1, suggesting its involvement in anthocyanin biosynthesis and male sterility in pepper. Conclusions In summary, we systematically characterized the phylogeny, classification, structure, and expression of the CaWD40 gene family in pepper. Our findings provide a valuable foundation for further functional investigations on WD40 genes in pepper.

The escalating global population, diminishing agricultural lands, and the overarching global climate crisis are significantly impacting pepper cultivation. These challenges exacerbate the vulnerability of pepper plants to various biotic and abiotic factors, particularly viral diseases, resulting in diminished yield and quality. Cucumber mosaic virus (CMV), a notable concern for peppers in the Solanaceae family, is causing substantial quality and yield losses, with no effective chemical control methods currently available. This study focuses on exploring the genetic structure of CMV isolates obtained from pepper production areas in Kilis province and comparing these regions through the High-Resolution Melting (HRM) method. CMV isolates, cultivated in tobacco plants, have their partial coat protein sequences compared with those of other CMV isolates registered in the gene bank. The nucleotide sequences of identified CMV isolates are phylogenetically grouped and compared using an HRM graph. The HRM graph effectively distinguishes Kilis 3 and Kilis 4 isolates, clustered similarly to sequence patterns, from other isolates. The study highlights the utility of HRM analyses in identifying differences between isolates before determining sequence patterns. In the gene bank comparison, Kilis CMV isolates distinguished from others. Similarities were observed with isolates from Iran's Balsam (Impatiens balsamina - LC066478), Türkiye's Radish (Raphanus sativus - LC0665051), and Wild Turnip (Rapistrum rugosum - LC066514, LC066511, LC066517). The study found that Kilis 7 CMV isolate, transferred mechanically to 24 different pepper genotypes (C. annuum) from the local population, revealed susceptibility to CMV in the 24 lines developed from the Elbeyli population in Kilis province.

Abstract [Objective] The study aims to explore the expression and function of the RIN gene, encoding a MADS-box, and analyze its impact on the metabolism of carotenoids in pepper. [Methods] Based on the fruit development transcriptome of pepper, the full-length CDS of the MADS-box transcription factor Ca- RIN gene related to chili ripening was cloned. The bioinformatics, expression pattern, subcellular localization, and transcriptional activation activity were examined, and the effects of VIGS-induced CaRIN gene silencing on carotenoid metabolism were investigated. [Results] (1) The CDS of CaRIN gene was 732 bp in length. CaRIN gene encoded a protein containing 243 amino acids with a molecular mass of 27.95 kD and an isoelectric point (pI) of 7.06. CaRIN protein had a typical MEF2_ like MADS domain, belonging to the MICK type transcription factor. (2) CaRIN gene was mainly expressed in flowers and fruits with tissue specificity. CaRIN was located in the nucleus and had transcriptional activation activity. (3) The promoter of CaRIN gene had several hormone response elements such as ABRE, and exogenous ABA and ethephon accelerated the fruit to turn red and induced the high expression of CaRIN and related genes. (4) After VIGS-induced gene silencing of CaRIN , the expression level of PSY1, CCS, PDS, CRTZ, LCYB, and NCED1, genes involved in carotenoid metabolic pathway, was decreased by 0.27-0.59 times, and the total carotenoid content in fruits (0.379 mg/g) was decreased compared with the control (0.650 mg/g). [Conclusion] CaRIN may be an important regulatory factor of carotenoid metabolism in capsicum fruits.

Pepper is one of the important vegetable crops and condiments in China. Carrying out researches on pepper genomics is of great significance for understanding the genetics and evolution of peppers, tapping important functional genes of peppers, and using biotechnology to conduct genetic improvement of varieties. The release of the draft pepper genomic map in 2014 marked the entry of pepper into an era of genomics research. Over the past decade, remarkable progress has been made in pepper genomics research, revealing the basic features of pepper genome deeply and constructing a preliminary pan-genome of pepper. Meanwhile, pepper genomics has been widely applied in exploring the interspecific differentiation and gene introgression of pepper, analyzing the evolutionary mechanism of pepper important traits, elucidating the genetic diversity of pepper, revealing the characteristics of artificial domestication of pepper, tracing the history of global range expansion and dissemination of pepper, and exploring the genes controlling the formation of important traits of pepper and so on. In this paper, we review and summarize the progress made in pepper genomics and its applications over the past 10 years, and look forward to the construction of a higher-quality pepper reference genome and pan-genome as well as the improvement of the research platform for pepper functional genomics, with an aim to provide a reference for pepper genomics and related applications.

【Objective】The study was carried out to explore the distribution patterns of rhizospheric microbial communities in different resistant pepper varieties, aiming to provide a basis for the targeted optimization of rhizospheric microbial community structure of pepper.【Method】Taking the susceptible pepper variety 'Hailan 99' (HL99) and the resistant variety 'Sanxiaqing' (SSQ) as experimental materials, high-throughput sequencing technology was employed to analyze and compare the effects of susceptible and non-susceptible soil environments on the community diversity, species composition, correlation networks and function of bacteria and fungi in the rhizosphere soil of different disease-resistant pepper plants.【Result】Through high-throughput sequencing, a total of 66 617 operational taxonomic units (OTUs) from soil bacterial samples were obtained, among which the dominant phyla were Proteobacteria and Bacteroidetes, with the relative abundances of approximately 40.1% and 15.3%, respectively. From soil fungal samples, 2 948 OTUs were obtained, among which the dominant phylum was Ascomycota, with an average relative abundance of approximately 47.8%. The rhizospheric microbial community structure and species composition of pepper varieties showed significant differences under different soil conditions. Under susceptible soil conditions, the diversity of bacterial communities in pepper rhizosphere decreased, while the diversity of fungal communities increased. The bacterial OTUs decreased by 6.5%-7.8%, and fungal OTUs increased by 8.8%-9.8%. The relative abundance of Fusarium fungi was significantly higher in the susceptible group (5.0%) compared with that in the resistant group (4.8%), while the relative abundance of beneficial fungi like Mortierella and Trichoderma and beneficial bacteria like Pseudomonas and Bacillus was significantly lower in the susceptible group than that in the resistant group. Overall, under the susceptible soil conditions, the abundance of beneficial rhizosphere fungi and bacteria in the resistant group was higher than that in the susceptible group, contributing to a better soil micro-ecological environment. Based on species abundance tables, the correlation relationships of fungi-fungi, fungi-bacteria and bacteria-bacteria species were calculated respectively at the genus level. The results indicated that the rhizosphere microorganisms of pepper formed a complex ecological network, with high co-occurrence between fungi-fungi and fungi-bacteria (with a positive correlation percentage higher than 50%), suggesting that cooperative relationships outweighed competitive ones. The bacteria-bacteria network structure was more complex, with a positive correlation percentage of about 49.9%.【Conclusion】The rhizospheric microbial community structures of different resistant varieties exhibit significant differences under different soil conditions. The interaction of rhizosphere microorganisms forms a complex microbial ecological network structure. The relative abundance of beneficial fungi and bacteria is higher in the resistant variety than that in the susceptible variety, which suppresses more pathogenic microbes, leading to a healthier soil micro-ecological environment. The key groups identified in this study, including Fusarium, Verticillium, Trichoderma, Bacillus and Pseudomonas, will provide important information for the targeted optimization of rhizospheric microbial community structures and offer crucial theoretical references for the biological control of soil-borne diseases.

Copyright of Journal of Food Safety & Quality is the property of Journal of Food Safety & Quality Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Bacterial wilt caused by Ralstonia solanacearum is one of the most important diseases in solanaceous plants, including peppers. It generally tends to be more serious under warm−temperature and moist (WM) conditions than at moist room−temperature (RM) conditions. Although immunity mechanisms at room temperature have been intensively studied, the mechanisms underlying WM conditions remain poorly understood. Herein, the pepper cysteine protease CaZingipain2 was expressed and functionally characterized in pepper immunity against R. solanacearum at WM conditions and at room temperature. The results showed that CaZingipain2 localized to the nucleus and was upregulated at the transcript level in pepper plants upon R. solanacearum infection under WM conditions (RSWM). Virus−induced gene silencing of CaZingipain2 significantly increased the susceptibility of pepper plants to RSWM, and was coupled with the downregulation of CaPRP1 and CaMgst3, which are specifically related to pepper immunity against RSWM, according to our previous studies, while its overexpression significantly reduced the susceptibility of N. benethamiana plants to RSWM compared to that of wild−type plants. In addition, our data showed that CaZingipain2 also acts positively in pepper immunity against R. solanacearum infection at room temperature by upregulating the SA− and JA−responsive PR genes, including CaNPR1 and CaDEF1. All these results indicate that CaZingipain2 improves pepper immunity against R. solanacearum under WM conditions and at room temperature by regulating different PR genes. [ABSTRACT FROM AUTHOR]

Background: The WD40 domain, one of the most abundant in eukaryotic genomes, is widely involved in plant growth and development, secondary metabolic biosynthesis, and mediating responses to biotic and abiotic stresses. WD40 repeat (WD40) protein has been systematically studied in several model plants but has not been reported in the Capsicum annuum (pepper) genome. Results: Herein, 269, 237, and 257 CaWD40 genes were identified in the Zunla, CM334, and Zhangshugang genomes, respectively. CaWD40 sequences from the Zunla genome were selected for subsequent analysis, including chromosomal localization, phylogenetic relationships, sequence characteristics, motif compositions, and expression profiling. CaWD40 proteins were unevenly distributed on 12 chromosomes, encompassing 19 tandem duplicate gene pairs. The 269 CaWD40s were divided into six main branches (A to F) with 17 different types of domain distribution. The CaWD40 gene family exhibited diverse expression patterns, and several genes were specifically expressed in flowers and seeds. Yeast two-hybrid (Y2H) and dual-luciferase assay indicated that CaWD40-91 could interact with CaAN1 and CaDYT1, suggesting its involvement in anthocyanin biosynthesis and male sterility in pepper. Conclusions: In summary, we systematically characterized the phylogeny, classification, structure, and expression of the CaWD40 gene family in pepper. Our findings provide a valuable foundation for further functional investigations on WD40 genes in pepper. [ABSTRACT FROM AUTHOR]

Capsaicinoids are produced uniquely in pepper fruits, and its level determines the commercial quality and health-promoting properties of pepper. So, it is particularly important to increase capsaicinoids content in pepper. Rhizosphere microbiota is critical to plant growth and performance, and affected by plant varieties. However, the impact of pepper varieties with different capsaicinoids yields on the rhizosphere microbiota is poorly understood. Using high-throughput sequencing of the 16S rRNA and internal transcribed spacer (ITS) region, we investigated the rhizosphere microbial community among five pepper varieties containing different capsaicinoids. Our results demonstrated that pepper variety significantly influenced the diversity and structure of rhizosphere microbial community. Bacterial diversity in varieties with high capsaicinoids content was significantly higher than in varieties with low capsaicinoids content, while fungal diversity was opposite to bacterial diversity. The correlation analysis revealed that 19 dominant bacterial genera (e.g., Chujaibacter, Rhodanobacter, and Gemmatimonas) were significantly correlated with capsaicinoids content, and nine of them were also significantly associated with soil nutrients, whereas only one fungal genus (Podospora) was significantly correlated with capsaicinoids content. Additionally, almost all genera which significantly correlated to capsaicinoids content were biomarkers of the five pepper varieties and the correlation was well corresponding to the capsaicinoids content. Overall, our results confirmed that the variety of pepper significantly affected the rhizosphere microbial community in the fields, and bacteria and fungi responded differently to capsaicinoids, which may affect the biosynthesis of capsaicinoids and contribute to further improvement of capsaicinoids production in pepper fruits. [ABSTRACT FROM AUTHOR]