Citrus Varieties Research Articles

Identification of Meloidogyne panyuensis (Nematoda: Meloidogynidae) infecting Orah (Citrus reticulata Blanco) and its impact on rhizosphere microbial dynamics: Guangxi, China

Root-knot nematode disease severely affects the yield and quality of the mandarin variety Citrus reticulata Blanco “Orah” in Guangxi, China. Nevertheless, the pathogen and the effects of this disease on microbial communities remain inadequately understood. This study identified the root-knot nematode Meloidogyne panyuensis in the rhizosphere of infected Orah using morphological and molecular biological methods. Soil chemical properties indicated that organic matter, total nitrogen (TN), total phosphorus (TP), available phosphorus (AP), total potassium (TK), and available potassium (AK) were significantly higher in the rhizosphere soil of M. panyuensis-infected Orah than in that of healthy plants. The relative abundance of the bacteria Bacillus, Sphingomonas, and Burkholderia-Caballeronia-Paraburkholderia, as well as the fungi Lycoperdon, Fusarium, Neocosmospora, Talaromyces, and Tetragoniomyces, was elevated in the rhizosphere soil of M. panyuensis-infected plants. Furthermore, organic matter, TN, available nitrogen (AN), TP, AP, TK, and AK exhibited positive correlationswith these bacteria and fungi in the rhizosphere soil of M. panyuensis-infected Orah. Potential biocontrol strains, such as Burkholderia spp., were identified by comparing the differences in rhizosphere microbial composition between healthy Orah and M. panyuensis-infected Orah. Our findings provide a foundation for the early warning and prevention of root-knot nematode disease in Orah.

Comparative transcriptomic analyses of diploid and tetraploid citrus reveal how ploidy level influences salt stress tolerance

IntroductionCitrus is an important fruit crop for human health. The sensitivity of citrus trees to a wide range of abiotic stresses is a major challenge for their overall growth and productivity. Among these abiotic stresses, salinity results in a significant loss of global citrus yield. In order to find straightforward and sustainable solutions for the future and to ensure citrus productivity, it is of paramount importance to decipher the mechanisms responsible for salinity stress tolerance. Thisstudy aimed to investigate how ploidy levels influence salt stress tolerance in citrus by comparing the transcriptomic responses of diploid and tetraploid genotypes. In a previous article we investigated the physiological and biochemical response of four genotypes with different ploidy levels: diploid trifoliate orange (Poncirus trifoliata [L.] Raf.) (PO2x) and Cleopatra mandarin (Citrus reshni Hort. Ex Tan.) (CL2x) and their respective tetraploids (PO4x, CL4x).MethodsIn this study, we useda multifactorial gene selection and gene clustering approach to finely dissect the influence of ploidy level on the salt stress response of each genotype. Following transcriptome sequencing, differentially expressed genes (DEGs) were identified in response to salt stress in leaves and roots of the different citrus genotypes.Result and discussionGene expression profiles and functional characterization of genes involved in the response to salt stress, as a function of ploidy level and the interaction between stress response and ploidy level, have enabled us to highlight the mechanisms involved in the varieties tested. Saltstress induced overexpression of carbohydrate biosynthesis and cell wall remodelling- related genes specifically in CL4x Ploidy level enhanced oxidative stress response in PO and ion management capacity in both genotypes. Results further highlighted that under stress conditions, only the CL4x genotype up- regulated genes involved in sugar biosynthesis, transport management, cell wall remodelling, hormone signalling, enzyme regulation and antioxidant metabolism. These findings provide crucial insights that could inform breeding strategies for developing salt-tolerant citrus varieties.

Full-length transcriptome characterization and analysis of Carrizo Citrange and molecular insights into pathogen defense.

Citrus huanglongbing (HLB) is a major challenge that impacts the flourishing of the citrus industry. Therefore, analyzing the genomic information of HLB-resistant or tolerant citrus resources is crucial for breeding HLB-resistant citrus varieties. The Carrizo citrange, a hybrid of Citrus sinensis and Poncirus trifoliata, plays a pivotal role in citrus cultivation. However, its genetic explorations are difficult due to the absence of a reference genome or full-length transcriptome. In order to enhance our understanding of the genetic information of citrange, we conducted a full-length transcriptomic sequencing of multiple tissues from the Carrizo citrange using the PacBio Sequel II platform. Moreover, we performed gene ontology (GO) annotation, gene functional annotation, simple sequence repeats (SSR) types analysis, as well as identification of lncRNAs, alternative splicing events, and analysis of pathogen defense-related genes. Results showed that a total of 43,452 isoforms were generated, with 43,307 of them being annotated. GO annotation indicated the involvement of these isoforms in various biological processes, cellular components, and molecular functions. The coding sequence length of the isoforms ranged from 1,000 to 4,000 base pairs (bp). Moreover, we have discovered 54 varieties of transcription factors and regulators, along with 16 classifications of genes associated with resistance. Among all types of SSRs, trimer type SSRs were the most abundant. 130 lncRNAs were predicted to be highly reliable in the isoforms of the Carrizo citrange, with alternative splicing events identified, and the most frequent being retained intron. The analysis of gene family expansion and contraction revealed a significant increase in pathogen defense-related genes within the Carrizo citrange. The results of this study will be of great value for future investigations into gene function in citrange and for expanding the genetic pool for breeding citrus varieties resistant or tolerant to HLB.

Loop-Mediated Isothermal Amplification Assay for the Detection of Citrus Canker Causing Bacterial Variant, Xanthomonas citri pv. citri Aw Strain

Citrus canker, a highly transmissible bacterial disease, has three major types, with Asiatic canker (Canker A), caused by Xanthomonas citri pv. citri (Xcc A), being the most widespread and severe, affecting most citrus varieties. Xcc A has two mild variants, Xcc A* and Aw with a limited host range, reported in Southwest Asia and Florida, respectively. Since 2015, the canker caused by Xcc Aw has been being reported in the Rio Grande Valley of South Texas where the Texas commercial citrus industry is located. In 2016, a more severe Canker A was reported in the upper Texas gulf coast region, north of the Rio Grande Valley, posing a potential threat to the Texas citrus industry. Given that existing diagnostic methods cannot reliably distinguish Xcc Aw from Xcc A, we developed a loop-mediated isothermal amplification (LAMP) assay specific to Xcc Aw (LAMP-Aw) for rapid, field-based identification of this bacterial variant. The detection limit of LAMP-Aw was ~4.52 Log10 copies of the target molecule. This study also evaluated the field applicability of the LAMP-Aw assay by coupling the LAMP-Aw assay with a lateral flow immunoassay system.

Grove-Level Analysis of the Titer and Prevalence of ‘Candidatus Liberibacter asiaticus’ and Wolbachia in Diaphorina citri, Vector of Citrus Huanglongbing

Huanglongbing (HLB, or citrus greening disease) affects all citrus varieties worldwide. In the United States, Asia, and South America, the causal agent is ‘ Candidatus Liberibacter asiaticus’ ( CLas), a phloem-limited, uncultured alphaproteobacterium. The hemipteran insect vector Diaphorina citri (Asian citrus psyllid) acquires and transmits CLas in a circulative, propagative manner. In addition to CLas, D. citri hosts multiple symbiotic bacterial species including Wolbachia (wDi). In D. citri, wDi has been sequenced and studied, but specific roles in D. citri biology are unknown. Using well-established quantitative PCR methods, we measured CLas titer in D. citri collected from four groves in central Florida with distinct HLB management strategies and tested whether CLas and wDi titer were correlated in a subset of these insects. Grove site had the largest effect on CLas titer. Sex had no effect on CLas titer, whereas a higher wDi titer was correlated with noninfected insects. Our results suggest that more directed follow-up research is necessary and important to clarify whether field management tactics influence CLas titer in D. citri and to better understand gene-by-environment interactions among D. citri, wDi, and CLas. Now that millions of trees in Florida have been treated with injectable formulations of oxytetracycline, which is likely to decrease bacterial populations in D. citri, this study may represent the last biologically meaningful snapshot of grove-level vector-pathogen ecology in the state during the HLB epidemic.

Estimation of the soluble solid content of citrus based on the fractional-order derivative and optimal band combination algorithm.

The soluble solid content (SSC) is a primary characteristic index for evaluating the internal quality of citrus fruits. The development of rapid and nondestructive SSC detection techniques can help address the current issues of postharvest quality grading in China's citrus industry. In this study, a total of 261 experimental samples, including 70 Murcott, 91 Clementine, and 100 Navel orange, were divided into prediction and validation sets in a 7:3 ratio. After obtaining the reflection spectra and SSCs, SNV-FOD (Standard Normal Variate-Fractional-Order Derivative) was used to process the spectra, and the optimal band combination algorithm was introduced to select SSC-sensitive bands. Then, the obtained optimal dual-band combination was input into eight regression models for comparison, and the best performing models stacked ensemble models was selected. Finally, the H-ELR (HyperOpt-optimized ensemble learning regression) model, optimized using a Bayesian function, was applied for the effective estimation of SSC for three common citrus varieties in Guangxi, Murcott, Clementine, and Navel oranges. The results show that (1) the SNV-FOD preprocessing method proposed in this study improved the correlation coefficient with the SSC from 0.546 to 0.836 compared to that of the original spectrum, (2) the optimal dual-band combination (969 and 1069nm) constructed by integrating the differential index and 1.2-order derivative yielded the most accurate results (RPD=2.13), and (3) the H-ELR model, based on HyperOpt optimization, achieved good estimated performance (RPD=2.46). PRACTICAL APPLICATION: This research contributes to the development of practical SSC prediction instruments with excellent universality and ease of application.

Agribusiness Prospects of Kachai Lemon Produced in Ukhrul District of Manipur, India: Status, Issues and Way Forward

Kachai lemon (Citrus jambhiri Lush.) is a variety of citrus, known for its rich nutritional and medicinal benefits due to its high flavonoid content and ascorbic acid. It has played a significant role in enhancing the socio-economic development of the tribal communities by generating income and employment opportunities. The Geographical Indication (GI) tag awarded to Kachai lemon has increased its commercial cultivation and market value. This recognition and growing attention have led to the emergence of agripreneurs and farmer producer organizations (FPOs) for production, value addition and marketing of Kachai lemon in an organized manner. The present study is aimed to compile the success stories, challenges of farmers and explore various Kachai lemon brands available on online platforms. A SWOT (Strength, Weakness, Opportunities and Threats) analysis on production and marketing of kachai lemon was performed. For the study, descriptive analysis was carried out to assess its potential, current status and challenges. The study suggests that in order to compete globally, it is crucial to develop strong post-harvest processing and marketing systems with support from agencies and institutions to provide valuable resources and market linkages to enhance efficiency and gain economic benefits.

Therapeutics Effects of the Genus Citrus in Anxiety Disorder

Background Anxiety and mood disorders are among the mental health diseases that have exponentially increased in prevalence owing to the hectic and stressful lifestyle. In addition to negatively impacting people’s physical health, this has resulted in a major psychological, social, and financial burden. A lot of emphasis has been placed on dietary and lifestyle modifications in the ongoing search for medication-free treatments. Investigating the connection between the consumption of specific fruits and vegetables and mental health issues such as depression has produced some intriguing and occasionally encouraging results. The genus Citrus with over 1300 species of plants is enriched with a plethora of polyphenolic compounds on the one hand and multicomponent volatile oil content on the other hand. Purpose The current work is centered on examining the range of phytoconstituents found in various citrus species—both underutilized and utilized—as promising avenues for future anxiolytic research. The work also details the proposed pharmacological mechanisms of isolated components and clinical trial advancements of selected citrus species. Methodology Various databases, including PubMed and ScienceDirect, were used to search and collect relevant literature published in the past 10 years (2014–2024). The Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) criteria recommended for drafting methodical reviews were followed. Results Initially, 1791 articles were collected through an electronic database search, irrelevant titles/abstracts (1449) and other types of articles (05) were excluded. Out of 342 assessed reports, 187 duplicate articles were excluded. Finally, list of 67 articles was included in this narrative review. Conclusion Although research and development, as well as the commercial use of several citrus varieties, have attracted some interest recently, analyzing neglected citrus species closely can help to improve their processing into well-known anxiolytic leads by revealing their untapped potential. The work emphasizes the extensive exploration of underutilized citrus species, which have a rich bioactive pro file and enormous potential in pharmaceutical research and development.

Diversity and Evolution of NLR Genes in Citrus Species.

NLR genes are crucial components of the effector-triggered immunity (ETI) system, responsible for recognizing pathogens and initiating immune responses. Although NLR genes in many plant species have been extensively studied, the diversity of NLR genes in citrus remains largely unknown. Our analysis revealed significant variations in the copy numbers of NLR genes among these species. Gene duplication and recombination were identified as the major driving forces behind this diversity. Additionally, horizontal gene transfer (HGT) emerged as the principal mechanism responsible for the increase in NLR gene copy number in A. buxifolia. The citrus NLR genes were classified into four categories: TIR-NBS-LRR (TNL), CC-NBS-LRR (CNL), RPW8-NBS-LRR (RNL), and NL. Our findings indicate that TNL, RNL, and CNL genes originated from NL genes through the acquisition of TIR and RPW8 domains, along with CC motifs, followed by the random loss of corresponding domains. Phylogenetic analysis suggested that citrus NLR genes originated alongside the species and underwent adaptive evolution, potentially playing crucial roles in the global colonization of citrus. This study provides important insights into the diversity of citrus NLR genes and serves as a foundational dataset for future research aimed at breeding disease-resistant citrus varieties.

Citrus yellow vein clearing virus infection triggers phloem remobilization of iron- and zinc-nicotianamine in citrus.

Citrus yellow vein clearing virus (CYVCV) is a worldwide and highly destructive disease of citrus, but the mechanisms involved in CYVCV-inhibited plant growth are not well understood. This study examined nutrient levels and their cellular distribution in different organs of healthy and CYVCV-affected citrus (Citrus reticulata 'Kanpei') plants. We found that CYVCV-infected plants exhibit characteristic symptoms, including a significant reduction in iron (Fe) and other elemental nutrients in the shoots. Our data suggest that CYVCV-induced chlorosis in citrus leaf veins is primarily due to iron deficiency, leading to reduced chlorophyll synthesis. Further analysis revealed a marked decrease in iron concentration within the pith and xylem of citrus petioles post-CYVCV infection, contrasting with increased Fe and zinc (Zn) concentrations in the phloem. Moreover, a substantial accumulation of starch granules was observed in the pith, xylem, and phloem vessels of infected plants, with vessel blockage due to starch accumulation reaching up to 81%, thus significantly obstructing Fe transport in the xylem. Additionally, our study detected an upregulation of genes associated with nicotinamide metabolism and Fe and Zn transport following CYVCV infection, leading to increased levels of nicotinamide metabolites. This suggests that CYVCV-infected citrus plants may induce nicotinamide synthesis in response to Fe deficiency stress, facilitating the transport of Fe and Zn in the phloem as nicotinamide-bound complexes. Overall, our findings provide insight into the mechanisms of long-distance Fe and Zn transport in citrus plants in response to CYVCV infection and highlight the role of nutritional management in mitigating the adverse effects of CYVCV, offering potential strategies for cultivating CYVCV-resistant citrus varieties.

Morphological Characterization, Polyphenolic Profile, and Bioactive Properties of Limoncella, an Ancient Mediterranean Variety of Sweet Citrus.

Limoncella of Mattinata, a rare and ancient Mediterranean citrus fruit, was investigated by sequence analysis of the ribosomal internal transcribed spacer regions, which assigns it as a variety of Citrus medica L. Morphological, chemical, and biomolecular approaches, including light and electron microscopy, HPLC-ESI-MS/MS, and antioxidant and anti-inflammatory assays, were used to characterize the flavedo and albedo parts, usually rich in bioactive compounds. The morphological findings showed albedo and flavedo cellular structures as "reservoirs" of nutritional components. Both albedo and flavedo hydroalcoholic extracts were rich in polyphenols, but they were different in compounds and quantity. The flavedo is rich in p-coumaric acid and rutin, whereas the albedo contains high levels of hesperidin and quercitrin. Antioxidant, anti-inflammatory, and genoprotective effects for albedo and flavedo were found. The results confirmed the health properties of flavedo and highlighted that albedo is also a rich source of antioxidants. Moreover, this study valorizes Limoncella of Mattinata's nutritional properties, cueing its crops' repopulation.

Genomic and metabolomic insights into the selection and differentiation of bioactive compounds in citrus

Bioactive compounds are playing an increasingly prominent role in breeding functional and nutritive fruit crops such as citrus. However, the genomic and metabolic basis for the selection and differentiation underlying bioactive compounds variations in citrus remain poorly understood. Here, we constructed a species-level variation atlas of genomes and metabolomes using 299 citrus accessions. A total of 19,829 significant SNPs were targeted to 653 annotated metabolites, among which multiple significant signals were identified for secondary metabolites, especially flavonoids. Significantly differential accumulation of bioactive compounds in phenylpropane pathway, mainly flavonoids and coumarins, were unveiled across ancestral citrus species during differentiation, which is likely associated with the divergent haplotype distribution and/or expression profiles of relevant genes, including p-coumaroyl coenzyme A 2'-hydroxylases, flavone synthases, cytochrome P450 enzymes, prenyltransferases and UDP-glycosyltransferases. Moreover, we elucidated the citrus varieties with excellent antioxidant and anticancer capacities, clarifying the robust associations between distinct bioactivities and specific metabolites. Thus, these findings provide citrus breeding options for enrichment of beneficial flavonoids and avoidance of the potential risk of coumarins. This study will illuminate the application of genomic and metabolic engineering strategies in developing modern healthy citrus cultivars.

Genome-wide investigation of glycoside hydrolase 9 (GH9) gene family unveils implications in orchestrating the mastication trait of Citrus sinensis fruits

Mastication trait of citrus significantly influences the fruit’s overall quality and consumer preference. The accumulation of cellulose in fruits significantly impacts the mastication trait of citrus fruits, and the glycoside hydrolase 9 (GH9) family plays a crucial role in cellulose metabolism. In this study, we successfully identified 32 GH9 genes from the Citrus sinensis genome and subsequently conducted detailed bioinformatics analyses of the GH9 family. Additionally, we profiled the spatiotemporal expression patterns of CsGH9 genes across four distinct fruit tissue types and six crucial developmental stages of citrus fruits, leveraging transcriptome data. Parallel to this, we undertook a comparative analysis of transcriptome profiles and cellulose content among diverse fruit tissues spanning six developmental stages. Furthermore, to identify the pivotal genes involved in cellulose metabolism within the GH9 family during fruit maturity, we employed correlation analysis between cellulose content and gene expression in varying tissues across diverse citrus varieties. This analysis highlighted key genes such as CsGH9A2/6 and CsGH9B12/13/14/22. Collectively, this study provides an in-depth analysis of the GH9 gene family in citrus and offers novel molecular insights into the underlying mechanisms governing the mastication trait formation in citrus fruits.

Development of Yein-Early, a Unique Fruit-Color and Leaf-Shape Mutant of Citrus unshiu, and Its Specific Selection Marker.

Citrus unshiu Marc. cv. Miyagawa-wase is one of the most widely cultivated citrus varieties on Jeju Island in Republic of Korea. Mutation breeding is a useful tool for inducing genetic diversity by causing genomic mutations in a short period of time. We previously conducted mutation breeding using gamma irradiation to develop new varieties of C. unshiu. Here, we describe one of these varieties, Yein-early, which has a redder peel, greater hardness, and higher sugar content compared with the wild type (WT). Yein-early leaves also showed a unique phenotype compared with the WT, characterized by longer longitudinal length, shorter transverse length, stronger curling, and longer petiole length. Genome resequencing of Yein-early and the WT uncovered significant single-nucleotide polymorphisms (SNPs) and insertions/deletions (InDels). These variations were crucial in identifying molecular markers unique to Yein-early. In addition, we developed an allele-specific PCR marker specifically targeting a homozygous SNP in Yein-early that distinguishes it from the WT and other citrus varieties. This study contributes to the understanding of pigment synthesis in fruits and provides a valuable tool for selection of the novel Yein-early variety in citrus breeding programs.

MOLECULAR CHARACTERIZATION AND PATHOGENICITY TEST ON CITRUS FRUITS BY GREEN MOLD AND BLUE MOLD

Citrus fruits are essential for preventing various health conditions, including diabetes, neurological diseases, and cancer. Among the postharvest diseases affecting citrus fruits, Penicillium digitatum and Penicillium italicum are particularly significant. This study aimed to characterize Penicillium spp. isolated from three citrus varieties: orange (Citrus sinensis), small orange, and Malta. Pathogenicity tests confirmed that these Penicillium isolates were capable of infecting the tested citrus fruits. For molecular characterization, PCR amplification of the D1/D2 domain of 26S rDNA was performed using universal primers, which target the conserved regions of the nucleotide sequence. The PCR products were inserted into the pGEM-T Easy vector and transformed into E. coli Dh5α. The presence of the D1/D2 domain was verified by endonuclease digestion with EcoR1. Sequencing was conducted using the T7 promoter primer, and the resulting DNA sequences were analyzed with the DNAMAN analysis system. Sequence analysis revealed that the D1/D2 region of 26S rDNA from the orange isolate showed 99% similarity with Penicillium sp., while the D1/D2 region from the small orange isolate had 99.84% similarity with P. digitatum strain CBS 112082. The D1/D2 region from the Malta isolate showed 100% similarity with P. digitatum. Multiple sequence alignments among the three Penicillium isolates revealed a 98.81% identity. This study highlights the use of molecular techniques for understanding the pathogenicity of Penicillium spp. in citrus fruits.

Citrus Fruits Produce Direct Defense Responses against Oviposition by Bactrocera minax (Diptera: Tephritidae).

Plants perceive and orchestrate defense responses when herbivorous insects are ovipositing. Fruits, as a crucial reproductive organ in plants, have rarely been researched on the responses to insect eggs. Here, we found that oviposition by the specialist insect Bactrocera minax in navel oranges activated the lignin synthesis pathway and cell division, causing mechanical pressure that crushed the eggs. Transcriptome and metabolome analyses revealed an enrichment of oviposition-induced genes and metabolites within the lignin synthesis pathway, which was confirmed by histochemical staining. Furthermore, hydrogen peroxide (H2O2) accumulation was observed at the oviposition sites. Plant defense-related hormones jasmonic acid (JA) and salicylic acid (SA) exhibited rapid induction after oviposition, while indole-3-acetic acid (IAA) activation occurred in the later stages of oviposition. Additionally, secondary metabolites induced by prior egg deposition were found to influence larval performance. Our studies provide molecular evidence that host fruits have evolved defense mechanisms against insect eggs and pave the way for future development of insect-resistant citrus varieties.

Management of Huanglongbing of Citrus: Lessons from São Paulo and Florida.

São Paulo, Brazil, and Florida, USA, were the two major orange production areas in the world until Huanglongbing (HLB) was discovered in São Paulo in 2004 and Florida in 2005. In the absence of resistant citrus varieties, HLB is the most destructive citrus disease known because of the lack of effective tools to reduce spread of the vector, Diaphorina citri (Asian citrus psyllid), and transmission of the associated pathogen, Candidatus Liberibacter asiaticus. In both countries, a three-pronged management approach was recommended and begun: planting only disease-free nursery trees, effective psyllid control, and removal of all symptomatic trees. In Brazil, these management procedures were continued and improved and resulted in relatively little overall loss of production. In contrast, in Florida the citrus industry has been devastated with annual production reduced by approximately 80%. This review compares and contrasts various cultural and pest management strategies that have been used to reduce infection by the pathogen and increase tolerance of HLB in the main orange-growing regions in the world.

Biocontrol of citrus fungal pathogens by lipopeptides produced by Bacillus velezensis TZ01.

Citrus diseases caused by fungal pathogens drastically decreased the yield and quality of citrus fruits, leading to huge economic losses. Given the threats of chemical pesticides on the environment and human health, biocontrol agents have received considerable attention worldwide as ecofriendly and sustainable alternative to chemical fungicides. In the present study, we isolated a Bacillus velezensis strain TZ01 with potent antagonistic effect against three citrus pathogenic fungi: Diaporthe citri, Colletotrichum gloeosporioides and Alternaria alternata. The culture supernatant of this strain exhibited remarkable antifungal activity on potato dextrose agar plates and detached leaves of five citrus varieties. Treatment with TZ01 culture supernatant obviously affected the hyphal morphology and caused nucleic acid leakage. The crude lipopeptides (LPs) extracted from the culture supernatant were found as the major active ingredients, and could maintain the activity under a wide range of temperature and pH and ultraviolet radiation. Furthermore, the type of LPs, produced in vitro, were explored. Whole-genome sequencing of TZ01 revealed secondary metabolite gene clusters encoding synthetases for non-ribosomal peptides and polyketide production, and gene clusters responsible for the synthesis of three important LPs (surfactin, iturin, and fengycin) were identified in the genome. The liquid chromatography-mass spectrometry analysis confirmed the presence of various homologs of surfactin A, bacillomycin D, and fengycin A in the extracted LPs. Taken together, these results contribute to the possible biocontrol mechanisms of B. velezensis strain TZ01, as well as providing a promising new candidate strain as a biological control agent for controlling citrus fungal pathogens.

Polymethoxylated flavone variations and in vitro biological activities of locally cultivated Citrus varieties in China

Citrus peels are rich in polymethoxylated flavones (PMFs), which have beneficial health and pharmacological properties. In this study, the profiles, variations, and biological activities of PMFs in the peel extracts of 27 Citrus varieties (eight species) native to China were investigated. UPLC-QTOF-MS/MS analysis revealed that mandarin accumulated more diversity and higher detectable PMF contents. Wangcangzhoupigan (ZPG) possessed the highest antioxidant capacity. Gailiangcheng (GLC) and Bingtangcheng (BTC), sweet oranges showed excellent inhibitory effects against pancreatic lipase and α-glucosidase, respectively. Most citrus extracts effectively inhibited the production of ROS and pro-inflammatory cytokines, while increasing the accumulation of anti-inflammatory cytokines. In addition, Limeng (LM), Cupig-oushigan (GSG), and Yanxiwanlu (YXWL) showed anti-proliferative effects against DU145 and PC3 cancer cells. This study provides a comprehensive PMF profile and biological activities of various citrus species and will benefit future functional citrus breeding practices aimed at designing plants rich in total or specific PMFs for health benefits.

Nutritional, Bioactive, and Health Potential of Pomelo (Citrus maxima): An Exotic Underutilized Fruit

Pomelo scientifically known as Citrus maxima belongs to the family Rutaceae and is one of the largest fruits among citrus varieties. Mainly pomelo comes in different flesh colors such as red, pink, light pink, and white. The principal pomelo fruit polyphenols are phenolic acids, flavonoids, anthocyanins, and tannins. Pomelo fruit generates a large number of wastes including peel, pomace, and seeds which are comprised of bioactive compounds. The bioactive compounds carried in waste improve health functionalities. The hesperidin, narirutin, naringin, and their aglycone (naringenin), which have traditionally been acknowledged to constitute a characteristic component of pomelo, are the fruit's major constituents. Also, pomelo fruit juice is high in vitamins A and C, and the peel offers high protein, carbohydrate, and mineral content. Pomelo production and processing of different byproducts have become a perfect and long-lasting resource for agriculture and the food industry. The wastes loaded with immense essential components in pomelo have great importance in terms of human health. To have unique goods, to increase high consumer acceptability, and to have health advantages, this work gives a summary of recent advancements made to date with nutritional benefits, bioactive elements, and health benefits of pomelo fruit.