Genome-wide identification and expression analysis of calmodulin and calmodulin-like genes in passion fruit (Passiflora edulis) and their involvement in flower and fruit development.

BACKGROUND: The calmodulin (CaM) and calmodulin-like (CML) proteins play regulatory roles in plant growth and development, responses to biotic and abiotic stresses, and other biological processes. As a popular fruit and ornamental crop, it is important to explore the regulatory mechanism of flower and fruit development of passion fruit. RESULTS: In this study, 32 PeCaM/PeCML genes were identified from passion fruit genome and were divided into 9 groups based on phylogenetic analysis. The structural analysis, including conserved motifs, gene structure and homologous modeling, illustrates that the PeCaM/PeCML in the same subgroup have relative conserved structural features. Collinearity analysis suggested that the expansion of the CaM/CML gene family likely took place mainly by segmental duplication, and the whole genome replication events were closely related with the rapid expansion of the gene group. PeCaM/PeCMLs were potentially required for different floral tissues development. Significantly, PeCML26 had extremely high expression levels during ovule and fruit development compared with other PeCML genes, suggesting that PeCML26 had potential functions involved in the development of passion fruit flowers and fruits. The co-presence of various cis-elements associated with growth and development, hormone responsiveness, and stress responsiveness in the promoter regions of these PeCaM/PeCMLs might contribute to their diverse regulatory roles. Furthermore, PeCaM/PeCMLs were also induced by various abiotic stresses. This work provides a comprehensive understanding of the CaM/CML gene family and valuable clues for future studies on the function and evolution of CaM/CML genes in passion fruit. CONCLUSION: A total of 32 PeCaM/PeCML genes were divided into 9 groups. The PeCaM/PeCML genes showed differential expression patterns in floral tissues at different development stages. It is worth noting that PeCML26, which is highly homologous to AtCaM2, not only interacts with multiple BBR-BPC TFs, but also has high expression levels during ovule and fruit development, suggesting that PeCML26 had potential functions involved in the development of passion fruit flowers and fruits. This research lays the foundation for future investigations and validation of the potential function of PeCaM/PeCML genes in the growth and development of passion fruit.

A New Species of the Anastrepha pseudoparallela Group (Diptera: Tephritidae) with a Synopsis of the Group in Brazil.

The genus Anastrepha contains some of the most important fruit pests in the Americas. It comprises more than 300 species, of which 129 occur in Brazil. The genus is divided into 26 species groups, including the pseudoparallela group with 31 species, whose known host plants are primarily fruits of the genus Passiflora (Passifloraceae). Fourteen species are recorded in Brazil. Here, a new species of Anastrepha reared from fruits of Passiflora actinia Hook. and Passiflora elegans Mast. from southern Brazil is described and illustrated. In addition, a synopsis of the Brazilian species of the pseudoparallela group is provided.

Mutating the arginine residue within the FRNK motif of telosma mosaic virus (TelMV) HC-Pro protein attenuates viral infection and confers effective protection against TelMV in passion fruit (Passiflora edulis).

BACKGROUND: Telosma mosaic virus (TelMV, Potyvirus, Potyviridae) is an emerging viral pathogen that threatens passion fruit plantations worldwide. However, an efficient strategy for controlling such a virus is not yet available. Cross protection is a phenomenon in which pre-infection of a plant with one mild strain prevents or delays subsequent infection by the same or closely related virus. HC-Pro is the potyviral encoded multifunctional protein involved in several steps of viral infection, including multiplication, movement, transmission and RNA silencing suppression. In this study, we tested whether it is possible to generate attenuated viral strains capable of conferring protection against severe TelMV infection by manipulating the HC-Pro gene. RESULTS: By introducing point mutation into the conserved motif FRNK of HC-Pro that is essential for RNA silencing suppression, we have successfully obtained three attenuated mutants of TelMV (R181K, R181D, and R181E, respectively). These attenuated TelMV mutants could systemically infect passion fruit plants without noticeable symptoms. Pre-inoculation of one of these attenuated mutants confers efficient protection against subsequent infection by severe TelMV strain. Moreover, we demonstrated that the HC-Pros harbored by the attenuated mutants exhibit reduced RNA silencing suppression activity in Nicotiana benthamiana leaves. CONCLUSION: The attenuated TelMV mutants developed in this study that are suitable for cross protection offer a practical, powerful tool to fight against TelMV for sustainable passion fruit production. © 2024 Society of Chemical Industry.

Ethyl Formate Fumigation for Controlling Two Major Aphid Pests, Aphis spiraecola and Aphis gossypii, on Passion Fruit, from Cultivation to Post-Harvest Storage.

Tropical and subtropical crops are being increasingly cultivated in South Korea, leading to an increase in damage by exotic insect pests. Consequently, ethyl formate (EF) is currently being considered for quarantine and pre-shipment fumigation. In this study, we evaluated the effectiveness of EF fumigation for controlling Aphis spiraecola Patch and Aphis gossypii Glover, two representative quarantine pests on passion fruit ("Pink Bourbon") during greenhouse cultivation and post-harvest storage. The efficacy of EF against both aphids in terms of the lethal concentration causing 50% mortality (LCt50%) and LCt99% was 1.36-2.61 g h/m3 and 3.73-7.55 g h/m3 under greenhouse conditions (23 °C), and 1.37-2.02 g h/m3 and 3.80-14.59 g h/m3 post-harvest (5 °C), respectively. EF at 4 g/m3 for 4 h resulted in 100% mortality of A. spiraecola, which was more resistant to EF, without causing phytotoxic damage to the trees in a 340 m3 greenhouse. Post-harvest fruit fumigation at 10 g/m3 for 4 h in a mid-size (0.8 m3) fumigation chamber resulted in complete disinfection. Moreover, the EF level decreased below the EF threshold within 10 min after natural ventilation in the greenhouse. Therefore, our results suggest EF fumigation as an effective method for controlling A. spiraecola and A. gossypii.

Aloe vera and tea polyphenols composite coating delays passion fruit senescence by promoting phenolic and flavonoid accumulation.

Passion fruits are highly perishable during postharvest storage and transportation, prompting the exploration of natural preservatives. This study investigates the synergistic effects of Aloe vera (ALV) and tea polyphenols (TP) coatings on quality retention, ripening modulation, and associated regulatory mechanisms in stored "golden" passion fruit (Passiflora spp.) at 10 °C. The application of a composite coating comprising 40 % ALV and 0.1 g/L TP led to notable improvements in fruit preservation over a 28-day storage period. At the day of 28, quantitatively, the ALV + TP treatment reduced weight loss by 41.60 %, shrinkage index by 28.13 %, and decay index by 50 %, significantly outperforming the control and individual treatments; the treated fruits exhibited enhanced firmness, reduced ethylene production, and the respiration peak was delayed about 6 days. Metabolomic analysis revealed pronounced alterations in key metabolic pathways, notably phenylpropanoid and flavonoid biosynthesis. Specifically, significant increases in metabolites such as phenolic acids (Feruloylmalic acid and Acropyrone) and flavonoids (Okanin-4'-O-glucoside, Apigenin-8-C-Arabinoside, Quercetin-3-O- (2'-O-galloyl) galactoside, and Catechin callate) were observed. Concurrently, transcript levels of key biosynthetic genes including cinnamate 4-hydroxylase (PeC4H), 4-coumarate-coenzyme a ligase (PeC4L), hydroxycinnamoyl transferase (PeHCT) and flavonol synthase (PeFLS) were significantly up-regulated by ALV + TP coating, indicating a robust activation of these pathways. The findings underscore the effectiveness of the ALV + TP composite coating as an environmentally friendly strategy for enhancing postharvest quality by promoting the accumulation of beneficial phenolic acids and flavonoids in passion fruits.

First Report of Alternaria gossypina Causing Stem Base Rot on Passilora edulis in Guangxi, China.

Passion fruit (Passilora edulis), known as the "king of fruit juices", is popular in southern China (Yuan et al. 2019). Stem base rot is a devastating disease of passion fruit commonly caused by several Fusarium spp. (Zakaria, 2022). In July 2022, typical symptoms of stem base rot were observed in a poorly managed "Qinmi No. 9" Golden passion fruit orchard in Jingxi (23°13'10"N, 106°5'23"E). The disease incidence had reached 40% (n=200) in the survey. Symptoms included ulceration and mutilation at the stem base, making the plants prone to breakage when pulled, wilting and drooping leaves above ground, and severe cases leading to the entire plant withering and dying. Fourteen plants with obvious symptoms were collected. Thin sections of plant tissue were cut from junction of sickness and health of stem, sterilized with ethanol and sodium hypochlorite, and placed on PDA medium at 28°C. Sixty fungal strains were obtained, 90% of which was identified as Fusarium based on morphology. 80% of Fusarium were F. oxysporum species complex (FOSC), but pathogenicity experiment showed all FOSC were weakly pathogenic. However, two severely pathogenic fungi with similar morphology but distinct from Fusarium were identified from the same plant. The representative strain C11 was selected for further study. C11 demonstrated a rapid growth rate, reaching a 90 mm diameter colony on PDA cultured at 25°C for 7 days. The colony displaced a round, flat shape with an overall light brown front, and cottony gray or light brown mycelium, while the reverse side was dark brown. Conidia production was observed as typically occurred in multiple chains after 14 days culture on OA medium, with round, oval or straight rod-like brown conidia ranging in size from 5.74-23.42×14.67-67.22, featuring 1-8 transverse septa and 0-3 mediastinum (Figure S1). For molecular identification, the internal transcribed spacer (ITS, OR616614), translation elongation factor 1-alpha (TEF, OR633298), alternaria major allergen (Alt a1, OR633294) gene, glyceraldehyde 3-phosphate dehydrogenase (GAPDH, OR633295), RNA polymerase subunit II gene (RPB2, OR633297), 18S Small subunit rDNA (SSU, OR616608) , 28S Large Subunit rDNA (LSU, OR616615), the KOG1058 gene regions (OR633296) and an approximately segment of the anonymous noncoding region (OPA10-2, OR633299) were amplified from C11 (Liu et al. 1999, Li et al. 2023, Andrew et al. 2009), and deposited in GenBank with accession number shown in the brackets. Phylogenetic trees were constructed in MEGA11 after splicing by BioEdit (Figure S3). Combining morphology and molecular analyses, C11 was identified as Alternaria gossypina (Woudenberg et al. 2015). To test the pathogenicity, the base of the seedling stem (20cm in height) of 50 healthy "Tainong No. 1" variety of purple passion fruit, which was more susceptible to stem-base rot, was puncture wound with needles, inoculated with 6 mm diameter colonies of fungi, and then wrapped in wet cotton (Ángel et al. 2018). Ten healthy seedlings inoculated with PDA were used as controls. These plants were cultured in an artificial greenhouse at 30±5℃with 80±5% humidity. After 15 days, the plants inoculated with C11 exhibited symptoms similar to those in the field, whereas the controls remained healthy. A. gossypina was reisolated from the diseased plant stems, with the morphology and GAPDH sequence consistent with the inoculated (Figure S1, S2). This is the first report of passion fruit stem rot caused by A. gossypina. This finding will aid in the prevention and control of stem rot in passion fruit.

Passion fruit by-products (Passiflora edulis f. flavicarpa) as a potential fat replacer in ice cream.

In recent years, people have become interested in consuming low-fat foods as this reduces the risk of obesity and cardiovascular disease. For this reason, this study optimized the incorporation of passion fruit epicarp (PFE) as a partial fat substitute in dairy ice cream. For this purpose, a central composite rotational design 22 was performed and 5 response variables were optimized, of which 4 variables were maximized (percentage overrun, hardness, adhesiveness, and color coordinates L*, a*, b*), while the melting rate was minimized as a function of two factors (% PFE and % fat). The stability of three types of ice cream was then evaluated: experimental ice cream (3% milk fat and 0.97% PFE), commercial ice cream (4% milk fat and 2% vegetable fat) and control ice cream (3% milk fat without PFE added), according to their physicochemical and sensory properties during 57 days of storage (-22 °C, 85% relative humidity). The results showed that it was possible to reduce the milk fat by up to 25% by adding PFE (0.97%), which significantly reduced the melting rate and resulted in higher hardness (N), adhesiveness and increased yellowness compared to the commercial samples. The optical microscopy analysis also showed that PFE keeps the air bubbles immobile due to the increased viscosity in the serum phase during the 57-day storage.

Physicochemical and Nutritional Properties of Vegetable Oils from Brazil Diversity and Their Applications in the Food Industry.

In this study, the oils of açaí, passion fruit, pequi, and guava were submitted to physicochemical analysis to investigate their potential application in the food industry. Gas chromatography associated with mass spectroscopy showed that oleic and linoleic acids are mainly responsible for the nutritional quality of açaí, passion fruit, pequi, and guava oils, which exhibited 46.71%, 38.11%, 43.78%, and 35.69% of the former fatty acid, and 18.93%, 47.64%, 20.90%, and 44.72% of the latter, respectively. The atherogenicity index of the oils varied from 0.11 to 0.65, while the thrombogenicity index was 0.93 for açaí, 0.35 for guava, and 0.3 for passion fruit oils, but 1.39 for pequi oil, suggesting that the use of the first three oils may lead to a low incidence of coronary heart disease. Thermogravimetry showed that all tested oils were thermally stable above 180 °C; therefore, they can be considered resistant to cooking and frying temperatures. In general, the results of this study highlight possible applications of these oils in the food industry, either in natura or in typical food production processes.

Piceatannol Upregulates SIRT1 Expression in Skeletal Muscle Cells and in Human Whole Blood: In Vitro Assay and a Randomized, Double-Blind, Placebo-Controlled, Parallel-Group Comparison Trial.

Piceatannol (PIC), a polyphenol abundant in passion fruit seeds, is reported to promote fat metabolism. This study investigated whether PIC affects sirtuin 1 (SIRT1) expression and metabolic factors in C2C12 skeletal muscle cells. C2C12 myotubes were stimulated with PIC, and alterations in gene expression, protein levels, mitochondrial DNA content, and fatty acid levels were assessed using real-time PCR, Western blotting, and Nile red staining. Furthermore, we examined changes in SIRT1 expression following the consumption of a test food containing 100 mg PIC for 2 weeks among adults with varying age and body mass index ranges. Both PIC and passion fruit seed extract induced SIRT1 expression in C2C12 myotubes to a greater extent than resveratrol. PIC also increased the expression of genes associated with mitochondrial biogenesis and fatty acid utilization, increased mitochondrial DNA content, and suppressed oleic acid-induced fat accumulation. Moreover, participants who consumed PIC exhibited significantly higher SIRT1 mRNA expression in whole blood compared to those in the placebo group. These findings suggest that PIC induces SIRT1 expression both in vitro and in the human body, which may promote mitochondrial biosynthesis and fat metabolism.

In vitro simulated digestion and fermentation characteristics of pectic polysaccharides from fresh passion fruit (Passiflora edulis f. flavicarpa L.) peel.

In this study, two pectic polysaccharides (PFP-T and PFP-UM) were extracted from fresh passion fruit peels using three-phase partitioning (TPP) and sequential ultrasound-microwave-assisted TPP methods, respectively, and their effects on the in vitro gastrointestinal digestion and fecal fermentation characteristics were examined. The results indicate that gastrointestinal digestion has a minimal effect on the physicochemical and structural characteristics of PFP-T and PFP-UM. However, during in vitro fecal fermentation, both undigested PFP-T and PFP-UM are significantly degraded and utilized by intestinal microorganisms, showing increased the total relative abundance of Firmicutes and Bacteroidota in the intestinal flora. Notably, compared with PFP-UM, PFP-T better promoted the reproduction of beneficial bacteria such as Prevotella, Megasphaera and Dialister, while suppressed the growth of harmful genera including Escherichia-Shigella, producing higher content of short-chain fatty acids. Therefore, our findings suggest that PFP-T derived from passion fruit peel has potential as a dietary supplement for promoting intestinal health.

Assessing high-temperature and pressure extraction of bioactive water-soluble polysaccharides from passion fruit mesocarp.

The mesocarp (albedo) of passion fruit is considered a waste product but rich in soluble fibers, especially pectins. Biological activity and health benefits of pectins have recently emerged, especially in colorectal cancer and attenuating inflammation. Pectin conventional extraction often uses mineral acids, which can be hazardous to the environment, and alternatives can be costly. Here, we assessed a high-temperature and pressure method to extract pectin from the passion fruit albedo and evaluated the differences from the water-soluble fractions extracted. HPSEC, HPAEC, FTIR-ATR, and HSQC-NMR were performed to identify and confirm the highly methylated homogalacturonan structures. The heat-modified samples showed a decreased molecular size compared to the untreated sample. Colorectal cancer cell lines showed reduced viability after being treated with different doses of modified samples, with two of them, LW-MP3 and 4, showing the most potent effects. All samples were detected inside cells by immunofluorescence assay. It was observed that LW-MP3 and 4 upregulated the p53 protein, indicating cell-cycle arrest and the cleaved caspase-9 in one of the cell lines, with LW-MP4 enhancing cell death by apoptosis. Since the modified samples were composed of hydrolyzed homogalacturonans, those probably were the responsible structures for these anti-cancer effects.

A 224-bp Indel in the Promoter of PeMYB114 Accounts for Anthocyanin Accumulation of Skin in Passion Fruit (Passiflora spp.).

Passion fruit (Passiflora spp.) is an important fruit tree in the family Passifloraceae. The color of the fruit skin, a significant agricultural trait, is determined by the content of anthocyanin in passion fruit. However, the regulatory mechanisms behind the accumulation of anthocyanin in different passion fruit skin colors remain unclear. In the study, we identified and characterized a R2R3-MYB transcription factor, PeMYB114, which functions as a transcriptional activator in anthocyanin biosynthesis. Yeast one-hybrid system and dual-luciferase analysis showed that PeMYB114 could directly activate the expression of anthocyanin structural genes (PeCHS and PeDFR). Furthermore, a natural variation in the promoter region of PeMYB114 alters its expression. PeMYB114purple accessions with the 224-bp insertion have a higher anthocyanin level than PeMYB114yellow accessions with the 224-bp deletion. The findings enhance our understanding of anthocyanin accumulation in fruits and provide genetic resources for genome design for improving passion fruit quality.

Potency of Dimethyl Dicarbonate on the Microbial Inhibition Growth Kinetics, and Quality of Passion Fruit (Passiflora edulis) Juice during Refrigerated Storage.

This study aimed to investigate the effectiveness of dimethyl dicarbonate (DMDC) at various concentrations (0-250 ppm) in inhibiting the growth of Escherichia coli TISTR 117 and spoilage microbes in passion fruit juice (PFJ) and its impact on the physicochemical and antioxidant quality of the juice during refrigerated storage. The highest log reduction in the total viable count, yeast/molds and E. coli was attained in PFJ samples with 250 ppm of DMDC (p ≤ 0.05) added. Microbial growth inhibition by DMDC followed the first-order kinetic model with a coefficient of determination (R2) and inhibition constants (k) ranging from 0.98 to 0.99 and 0.022 to 0.042, respectively. DMDC at 0-250 ppm showed an insignificant effect on pH, °Brix, color (L*, a*, b*), ascorbic acid, total phenolic compound (TPC), total flavonoid content, and antioxidant activity (DPPH, FRAP) (p > 0.05). Control (untreated PFJ), DMDC-250 ppm, and pasteurized (15 s at 72 °C) samples were subjected to 27 days of cold storage at 4 °C. A decreasing trend in pH, total soluble solid, ascorbic acid content, DPPH and FRAP values were observed in all the samples during refrigerated storage. However, the DMDC-250 ppm sample showed a better prospect in physicochemical quality changes compared to the pasteurized and untreated control PFJ samples. ΔE values showed marked changes in the control sample than the DMDC-250 ppm and pasteurized samples at 27 days of storage. Additionally, the total viable count and yeast/mold count were augmented during storage, and an estimated shelf-life of the control, DMDC-250 ppm, and pasteurized samples was approximately 3, 24 and 18 days, respectively. In conclusion, DMDC at 250 ppm could ensure microbial safety without affecting the quality attributes of PFJ during 24 days of storage at 4 °C.

Nondestructive Determination of Epicarp Hardness of Passion Fruit Using Near-Infrared Spectroscopy during Storage.

The hardness of passion fruit is a critical feature to consider when determining maturity during post-harvest storage. The capacity of near-infrared diffuse reflectance spectroscopy (NIRS) for non-destructive detection of outer and inner hardness of passion fruit epicarp was investigated in this work. The passion fruits' spectra were obtained using a near-infrared spectrometer with a wavelength range of 10,000-4000 cm-1. The hardness of passion fruit's outer epicarp (F1) and inner epicarp (F2) was then measured using a texture analyzer. Moving average (MA) and mean-centering (MC) techniques were used to preprocess the collected spectral data. Competitive adaptive reweighted sampling (CARS), successive projection algorithm (SPA), and uninformative variable elimination (UVE) were used to pick feature wavelengths. Grid-search-optimized random forest (Grids-RF) models and genetic-algorithm-optimized support vector regression (GA-SVR) models were created as part of the modeling process. After MC preprocessing and CARS selection, MC-CARS-Grids-RF model with 7 feature wavelengths had the greatest prediction ability for F1. The mean square error of prediction set (RMSEP) was 0.166 gN. Similarly, following MA preprocessing, the MA-Grids-RF model displayed the greatest predictive performance for F2, with an RMSEP of 0.101 gN. When compared to models produced using the original spectra, the R2P for models formed after preprocessing and wavelength selection improved. The findings showed that near-infrared spectroscopy may predict the hardness of passion fruit epicarp, which can be used to identify quality during post-harvest storage.

Comparative genomics and bioinformatics approaches revealed the role of CC-NBS-LRR genes under multiple stresses in passion fruit.

Passion fruit is widely cultivated in tropical, subtropical regions of the world. The attack of bacterial and fungal diseases, and environmental factors heavily affect the yield and productivity of the passion fruit. The CC-NBS-LRR (CNL) gene family being a subclass of R-genes protects the plant against the attack of pathogens and plays a major role in effector-triggered immunity (ETI). However, no information is available regarding this gene family in passion fruit. To address the underlying problem a total of 25 and 21 CNL genes have been identified in the genome of purple (Passiflora edulis Sims.) and yellow (Passiflora edulis f. flavicarpa) passion fruit respectively. Phylogenetic tree was divided into four groups with PeCNLs present in 3 groups only. Gene structure analysis revealed that number of exons ranged from 1 to 9 with 1 being most common. Most of the PeCNL genes were clustered at the chromosome 3 and underwent strong purifying selection, expanded through segmental (17 gene pairs) and tandem duplications (17 gene pairs). PeCNL genes contained cis-elements involved in plant growth, hormones, and stress response. Transcriptome data indicated that PeCNL3, PeCNL13, and PeCNL14 were found to be differentially expressed under Cucumber mosaic virus and cold stress. Three genes were validated to be multi-stress responsive by applying Random Forest model of machine learning. To comprehend the biological functions of PeCNL proteins, their 3D structure and gene ontology (GO) enrichment analysis were done. Our research analyzed the CNL gene family in passion fruit to understand stress regulation and improve resilience. This study lays the groundwork for future investigations aimed at enhancing the genetic composition of passion fruit to ensure robust growth and productivity in challenging environments.

Immediate effects of passion fruit juice supplementation on working ability and attention in healthy participants.

This study investigated the effects of a single consumption of passion fruit juice (PFJ) on working ability and attention. It included 14 healthy participants aged 20-30 years. Participants randomly consumed either placebo or 50% PFJ at 3.5 mL/kg body mass. Each intervention was divided into two phases (before and after consumption). Before consumption, the participants underwent blood glucose, blood pressure, and heart rate examinations. Then, working ability and attention were evaluated. Thereafter, the blood glucose, blood pressure, and heart rate were repeatedly examined. Next, the participants completed consumption. After consumption, the participants underwent the same experiments performed before consumption. The total working ability scores after consumption were significantly high in both interventions (P < 0.05). However, PFJ intervention had a significantly higher working ability at 1, 2, 3, 4, and 5 min than placebo intervention (P < 0.05). Moreover, PFJ intervention had greater increases in attention than placebo intervention. There were no significant differences in attention between two interventions. The blood glucose levels were significantly lower in PFJ intervention than in placebo intervention both before the working ability test and after the attention test (P < 0.05). A single consumption of PFJ improved working ability in healthy participants. This may be enhanced by improving attentional focus and maintaining postprandial blood glucose.

Volatile aroma compounds of passion fruit seed Oils: HS-GC-IMS analysis and interpretation.

The physicochemical properties, fatty acid composition and volatile aroma compounds of cold-pressed passion fruit seed oils were analyzed. The oils were rich in linoleic acid, oleic acid and volatile compounds. A total of 108 volatile compounds including 17 aldehydes, 23 alcohols, 21 esters, 19 ketones, 6 acids, 9 alkenes, 5 pyrazines and 8 others were identified using HS-GC-IMS. The significant differences of volatile compounds in the purple and yellow passion fruit seed oils were observed via the GalleryPlot graph and distinguished by principal component analysis. The results showed that acids, alcohols, esters and ketones were major aromatic compounds in purple passion fruit seed oils, which contribute to flavors such as flowery, fruity, creamy, yogurt. Whereas the contents of aldehydes, pyrazines, alkenes were higher in yellow passion fruit seed oils, which contributes to fatty and nutty odors. The findings filled in our understanding of volatilization characteristics in passion fruit seed oils.

First report of Rhizopus stolonifer causing flower rot of yellow passion fruit (Passiflora edulis f. flavicarpa Deg.) in China.

The genus Passiflora, commonly known as passion fruit, originated in South America, is an economically important horticulture crop and widely distributed in the tropics and subtropics. Yellow passion fruit (Passiflora edulis f. flavicarpa) and purple passion fruit (Passiflora edulis f. edulis) are the two most planted species (Santos-Jiménez et al., 2022), which have been largely cultivated in southern China. The average annual production reaches 600,000 tons, of which yellow fruit accounts for more than 70% (Zhou et al., 2022). In 2022 to 2023, a disease caused flower rot severely in passion fruit plantations. The incidence rate was generally 10% in purple passion fruit, with an incidence up to 60% in yellow passion fruit 'Qinmi No. 9'. Flower rot occurs mainly in the rainy season, especially during periods of prolonged rain. Infected flowers had black patches that were water-soaked on the interior of the flower bud. The patches covered the entire flower bud, and fluffy mycelium and sporangia developed, which caused the flower bud rotten and abscised easily. Five symptomatic flowers from Wuhua, Guangdong (23°23'N, 115°18'E) and 8 symptomatic flowers from Shangsi, Guangxi (21°15'N, 107°98'E) of 'Qinmi No. 9' were collected during flowering period in 2022 and 2023. Diseased flower pieces were surface-sterilized with 70% ethanol for 2 to 3 min, rinsed with sterile distilled water 3 times, and placed on PDA medium at 25℃ in darkness. Four and 6 fungal isolates with similar morphology were isolated from the infected samples of Wuhua and Shangsi, respectively. Two isolates, PRFJ01 from Wuhua and PRGX02 from Shangsi, were randomly selected for further study. Purified fungal colonies at the age of 3 days accompany with diffuse cottony mycelia, turned white to gray later. The mycelia were hyaline and aseptate. Sporangiophores with 0.56 (0.22~1.10) mm in length and 6.1 (3.18~10.87) µm in width (n=100) were erect, light brown, and had rhizoids and stolons at their bases. Sporangia with 48.0 (23.45~92.85) µm in diameter (n=100) were dark-colored, near spherical and having dark ovoid sporangiospores with 3.56 (2.34~6.39) µm × 2.82 (1.73~4.70) µm (n=100). The morphology of the fungus were identical to Rhizopus stolonifer (Ehrenb.) Vuill (Haque et al. 2023). The two isolates were molecularly identified using genomic regions of 28S large ribosomal subunit (LSU) with NL1 and LR3 primers (Cruz-Lachica et al., 2018). The phylogenetic trees revealed the sequences of PRFJ01 (OR801560.1) and PRGX02 (OR801561.1) were 100% and 99% identical to R. stolonifer (MK705761.1 and KC412868.1), respectively. Pathogenicity tests were conducted on healthy flowers and leaves of 5-month-old grafted 'Qinmi No. 9' plants. Mycelial plugs with 5-mm diameter were placed on the flowers and leaves. Three plants were performed for each of the isolates, and the test was repeated twice. The inoculated plants were moisturized with plastic bags. Healthy flowers and leaves inoculated with sterile PDA plugs were used as control. Typical symptoms were observed on inoculated plants after 2 days. The dark grey mycelia and sporangia covered the entire flower after 4 days inoculation. The flower bud became putrid and the flower stalk split off. Lesions on leaves expanded accompany with numerous aerial mycelium. However, the controls were symptomless. R. stolonifer was reisolated from inoculated tissues. Previously, flower rot on passion fruit caused by R. stolonifer has only been recorded in Brazil (Ploetz, 2003). To our knowledge, this is the first report of R. stolonifer causing flower rot on passion fruit in China.

First Report of Root-knot Nematode, Meloidogyne enterolobii on Passiflora edulis in Yulin, China.

Passion fruit (Passiflora edulis), a medicinal plant, was introduced into China in the early 19th century, is mainly cultivated in southern provinces (Liang et al. 2019). During March 2023, a survey was carried out and 167 samples were taken from passion fruit cultivated area in Yulin (22.6570263°E; 110.1765019°N) apart from the planting base appeared yellow leaves, stunted growth, and distinctive galls on the roots. Within the galls, Meloidogyne sp. females and egg masses were observed. From the rhizosphere soil, second-stage juveniles (J2) were extracted, and population density was 105/500 g soil. The species was determined to be Meloidogyne enterolobii based on morphological characteristics, including female perineal pattern, and genetic analyses. Female (n = 10) perineal patterns showed oval shape, with coarse and smooth striae, dorsal arch rounded to square, and lateral lines not distinct. The male head cap was high and rounded, with the head region only slightly set off from the body, knobs large, ovoid to rounded. The measurements of males (n = 10) included body length, 1,230.7 ± 244.94 (997 to 1,569) µm; a, 38.58 ± 7.8 (33.45 to 47.05) µm; c, 113.03 ± 26.22 (80.82 to 144.23) µm; stylet, 15.68 ± 1.1 (14.5 to 17.4) µm; spicules, 31.83 ± 2.84 (28.69 to 36.1) µm; tail, 11.09 ± 1.72 (8.02 to 13.38) µm; and gubernaculum length, 8.34 ± 0.28 (8.11 to 8.98) µm. Measurements of J2 (n = 20) included body length, 455.75 ± 44.94 (381 to 512) µm; a, 26.32 ± 3.89 (18.18 to 32.70) µm; c, 8.56 ± 1.2 (6.36 to 10.80) µm; stylet, 12.44 ± 0.76 (11.2 to 13.8) µm; DGO, 3.65 ± 0.54 (2.84 to 4.68) µm; tail, 53.89 ± 6.36 (39.8 to 62.2) µm; and hyaline tail terminus, 11.77 ± 2.83 (7.14 to 16.2) µm. These morphological characteristics are similar to those reported in the original description of M. enterolobii (Yang and Eisenback 1983). The sequences of the partial ITS region was amplified with V5367 (5'-TTGATTACGTCCCTGCCCTTT-3') and 26S (5'-TTTCACTCGCCGTTACTAAGG-3') primers (Vrain et al. 1992). The region between cytochrome oxidase subunit II (COII) and the 16S rRNA mitochondrial DNA (mtDNA COII) was also amplified with the primers C2F3 (5'-GGTCAATGTTCAGAAATTTGTGG-3') (Powers and Harris 1993) and MRH106 (5'-AATTTCTAAAGACTTTTCTTAGT-3') (Stanton et al. 1997). The ITS region yielded a fragment of 757 bp (OR072957) and mtDNA COII of 706 bp (OR078415). A BLAST search indicated the sequences were 100% identical to several sequences of M. enterolobii (MT406250, MH756127 and AY831967, MN269940, respectively). To confirm pathogenicity, 20 passion fruit (P. edulis Sim. f. flavicarpa) 30-day-old seedlings were transplanted into pots with an autoclaved mixture of sand and field soil (3:1) and maintained in the glasshouse at 25 ± 2°C with 65 ± 5% relative humidity. After eight weeks, fifteen plants were inoculated with 500 J2/pot (nematode culture collected from the original field), and another five uninoculated plants served as a control. Two months later, aboveground symptoms were similar to those observed in the field. Nematode reproduction occurred and root galls were observed. The reproduction factor (nematode final population density/initial population density) was 4.8. The disease caused by M. enterolobii was severe in Yulin city of Guangxi. Guangxi is an important area for passion fruit culture, with about 2000 ha, which is responsible for two-thirds of China production (Xing et al. 2020). This is the first record of P. edulis natural infection with M. enterolobii in the Yulin City of Guangxi, China.

Association of Non-host Crop Plants with Mandarin in Host Location and Survival of Diaphorina citri Kuwayama (Hemiptera: Psyllidae).

Research efforts have been made to develop novel tactics, such as those targeting behavioral control, for management of the Asian citrus psyllid Diaphorina citri Kuwayama (Hemiptera: Psyllidae), vector of the causal agent of citrus Huanglongbing. Here, we investigated whether association of "Ponkan" mandarin (Citrus reticulata) with volatiles from non-host crops: avocado, passion fruit or coffee, alters host location by the Asian citrus psyllid; and whether they can be temporary hosts for the Asian citrus psyllid. In wind tunnel assays, we found that the association of mandarin seedling with avocado plant volatiles reduced in 30% the number of psyllids sitting on host plants compared to the mandarin alone. In contrast, passion fruit plant volatiles facilitated host location by psyllids, which found mandarin seedlings faster than when exposed to mandarin alone. The association with coffee volatiles did not alter the attractiveness of mandarin to the Asian citrus psyllid. Survival and half-lethal time (LT50) of D. citri fed on non-host plants were longer than those insects with water only, but shorter than those fed on mandarin. Among the non-host plants, D. citri performed better in coffee, followed by avocado and passion fruit plants. Our results indicate that the association of mandarin with avocado plant can be beneficial for Asian citrus psyllid management.