Infected Fruit Research Articles

First report of Alternaria alternata causing postharvest fruit rot of sweet orange in Anhui province, China.

As an important cash crop, sweet orange (Citrus sinensis Osbeck cv. Newhall) is globally cherished by consumers for its health-promoting properties. March 2024, orange postharvest rot was found in three markets in Anqing, Anhui Province, China, with an incidence of 15% to 20%. The initial symptom was the appearance of small, light to dark brown spots on the surface of the fruit, which later expand and cause the fruit to rot. To isolate the pathogen, ten 5 × 5 mm pieces of symptomatic tissue from the infected oranges were surface sterilized in 1% Sodium hypochlorite for 60 s, rinsed three times with sterile water, and plated onto potato dextrose agar (PDA) at 25°C for 7 days. The pure culture was obtained by transferring single-spore isolates to fresh PDA medium. Ten isolates with similar morphological characteristics were isolated, and all of the colonies were dark brown with white margins and abundant aerial mycelium and sporulation. Conidia were pale to dark brown in chains or singly and were obclavate to obpyriform, measuring 5.6 to 28.0 × 4.7 to 16.3 μm (n = 30) with 1 to 5 transverse septa and 0 to 3 longitudinal septa. Their morphological characteristics were consistent with the description of Alternaria sp. (Simmons 2007). For molecular identification, we arbitrarily selected five isolates and named them CZ-1 to 5 for further investigation. The genomic DNA of CZ-1 to 5 was extracted, and the internal transcribed spacer (ITS) region, translation elongation factor 1-alpha (TEF1) gene, and partial sequence of the β-tubulin (TUB2) gene were amplified with primers ITS1/ITS4, TEF1-F/TEF1-R (Zhang et al. 2020), and T1/T2 (O'Donnell and Cigelnik 1997), respectively. Sequences of the three loci from the representative isolate CZ-1 were deposited in GenBank (PP911430, PP928092, and PQ040398) and shared 100% nucleotide identity with Alternaria alternata sequences FJ717733, MH708309, and MN175551, respectively. A phylogenetic analysis was conducted using MEGA11 based on concatenated sequences of the three sequences, indicating that the isolates were closely clustered with reference strains of A. alternata. To evaluate pathogenicity, six surface-sterilized orange fruit with or without wounding were inoculated with a 20-μl drop of spore suspension (1 × 106 conidia/ml) of the isolates CZ-1 and -2. Another six fruit treated with sterile water with and without wounding were used as controls. All fruit were incubated in an artificial climate chamber at 25°C and 70 to 80% relative humidity for 7 days. Light to dark brown necrotic lesions at the wound sites appeared similar to those observed in the fruit markets, whereas control and nonwounded fruit remained healthy. The pathogens were re-isolated from the infected fruit, fulfilling Koch's postulates. The fungal pathogen A. alternata is widely distributed across various host plant species globally and has been documented as a causal agent of postharvest rot in kiwifruit (Li et al. 2017) and sweet cherry (Ahmad et al. 2020) in China. To our knowledge, this is the first report of A. alternata causing postharvest fruit rot of orange in Anhui province, China. The findings of this study will serve as a foundation for effectively managing the postharvest disease epidemic and prolonging the shelf life of oranges.

Caffeic acid improves biocontrol effect of Pantoea jilinensis D25 against tomato gray mold.

Gray mold in tomato caused by Botrytis cinerea is a destructive disease, which can be treated using biocontrol agents. Pretreatment of biocontrol strains with oxidative-stress-ameliorating compounds can enhance their tolerance to oxidative microenvironment in infected fruit wounds. In this study, we aimed to determine the effect of caffeic acid (CA) on the biocontrol efficacy of Pantoea jilinensis D25 in gray mold in cherry tomato. D25 strain pretreated with CA exhibited enhanced oxidative stress response in cherry tomato wounds. CA-treated D25 cells recovered from cherry tomato wounds had lower ROS level and cellular oxidative damage than D25 cells not treated with CA. The antioxidation-related genes (CAT and GPX) were upregulated and colonization ability of D25 strain was improved in cherry tomato wounds after CA application. Furthermore, the biocontrol effects of CA-treated D25 strain were improved. CA pretreatment to D25 strain could significantly improve the expression of defense-related genes (SlMYC-2, SlLoxD, SlEIN2, and SlEIN3) and activity of defense-related enzymes in cherry tomato wounds. Application of CA to D25 strain could improve its ability to combat antioxidant stress and biocontrol efficacy against postharvest tomato gray mold. © 2024 Society of Chemical Industry.

Assessing the Photocatalytic Degradation of Penconazole on TiO2 in Aqueous Suspensions: Mechanistic and Ecotoxicity Studies in Aerated and Degassed Systems

Penconazole (C12H15Cl2N3) is widely used to prevent fungal infection of fruits. Since this toxic fungicide is recalcitrant to biological degradation, it has harmful impacts on aquatic ecosystems. TiO2-based heterogeneous photocatalysis proved to be an efficient method for its mineralization. To monitor the processes occurring under the influence of illumination, the light absorbance, the pH, and the TOC of the samples were measured. The concentration of the model compound and the degradation products were determined by HPLC and IC. Penconazole did not decompose under UV light (λmax = 371 nm) without a catalyst. In the presence of TiO2, mineralization took place. The initial degradation rate in air (7.7 × 10−4 mM s−1) was 5 times higher than under argon. The formation rate of hydrochloric acid (1.04 × 10−3 mM s−1) in the former case significantly contributed to the acidification of the liquid phase. NH4+ also formed, at the rate of 5.9 × 10−4 mM s−1, and very slightly transformed to NO3−. Due to the intermediates identified by HPLC-MS, hydroxylation, H abstraction, and Cl elimination are involved in the degradation mechanism, in which photogenerated HO● radicals, conduction-band electrons, and (under air) superoxide radical anions (O2●−) play considerable roles. The intermediates proved to be much less toxic than penconazole.

Developmentally regulated generation of a systemic signal for long-lasting defence priming in tomato.

Tomato is a major global crop. However, its production is limited by Botrytis cinerea. Due to the toxicity of postharvest pesticide application, alternative control methods such as priming are being investigated. Plants were treated with β-aminobutyric acid (BABA) at two developmental stages and resistance against B. cinerea was tested in fruit tissue and in progenies. DNA methylation and RNA sequencing were conducted to characterise the (epi)genetic changes associated with long-lasting resistance. Grafting experiments were done to assess the systemic nature of this signal, which was further characterised by small RNA (sRNA) sequencing of scions. Only BABA-treated seedlings displayed induced resistance (IR). DNA methylation analysis revealed seedling-specific changes, which occurred in the context of lower basal methylation. BABA-IR was found to be transmissible from primed rootstock to grafted unprimed scions. In these scions, we identified a subset of mobile 24 nt sRNAs associated with genes showing primed expression during infection in fruit. Our results demonstrate the functional association of a systemic signal with long-lasting IR and priming. Through integrated omics approaches, we have identified markers of long-lasting priming in tomato fruit which could also serve as targets for durable resistance in other crops.

Phenylpropanoid pathway mediated the defense response of ‘Korla’ fragrant pear against Alternaria alternata infection

Alternaria alternata has been found to be the dominating pathogenic fungus of harvested ‘Korla’ fragrant pear, and the resulting blackhead disease is a significant factor affecting the storage quality of pears. The present study explored the specific mechanisms by which the phenylpropanoid pathway mediates the defense response to A. alternata infection in pear fruit. In the A. alternata-inoculated group, the fruit exhibited increased activity and gene expression levels of key enzymes (PAL, C4H, and 4CL) as well as higher content of phenolic acids (trans-cinnamic acid, ferulic acid, caffeic acid, p-coumaric acid, and sinapic acid) and total phenol in the general phenylpropanoid pathway. In the mid-to-late storage period, the activity and gene expression levels of key enzymes in the lignin biosynthetic pathway (CCR and CAD) were suppressed, and the content of lignin monomers (sinapyl alcohol, coniferyl alcohol, and p-coumaryl alcohol) and lignin was reduced. Notably, the activity and gene expression levels of flavonoid biosynthetic pathway-related enzymes (CHS and CHI) as well as the content of various flavonoids (naringenin, apigenin, rutin, quercetin, and epicatechin) and total flavonoids continuously increased in response to A. alternata infection in the early to middle stages of storage but declined in the late storage period. In summary, the initial infection of A. alternata infection activated the stress response of pear fruit, particularly the phenylpropanoid–flavonoid branch pathway, to enhance the fruit’s defense against pathogens, but with the prolongation of the infestation time, the fruit could not continuously resist the invasion of pathogens, ultimately leading to the outbreak of disease. The present findings furnish a theoretical foundation further elucidating the interaction between ‘Korla’ fragrant pear and A. alternata and for developing an effective strategy to control the blackhead disease.

Dynamic spatial network simulation accounting for multiple ecological factors provides practical recommendations for biosecurity early detection and rapid response (EDRR) strategies.

Globally the spread of invasive pests is being facilitated by increased human mobility and climate change. Simulation modelling can help assess biosecurity strategies for early detection and rapid response (EDRR), but has struggled to account for important factors in the invasion process, such as spatial and temporal variability in habitat suitability and connectivity; population dynamics; and multiple dispersal pathways. We developed a novel dynamic spatial network simulation approach based on spatial network theory that enables integration of a wider range of spatio-temporal factors than previous studies, calibrated it against extensive historical trapping data, and applied it to comprehensively analyse the EDRR strategy for Oriental fruit fly (Bactrocera dorsalis; OFF) in northern Australia. Simulations indicated that the chance of OFF reaching the mainland in the next 20 years could be up to 20% under the current EDRR strategy, depending on how optimistic or pessimistic model assumptions are, and highlighted possible improvements to the EDRR strategy for further consideration. Simulations under optimistic assumptions indicate that transport via wind is most important in OFF reaching the mainland, but under pessimistic assumptions transport via people carrying infected fruit becomes more important. Our new dynamic spatial network simulation approach can account for a wide range of spatio-temporal ecological factors to provide practical real-world recommendations. At a minimum, this approach only requires weather and population data, both of which are available globally from a variety of free and open sources, making it broadly applicable to assessing the EDRR strategies in place for different species in other locations. © 2024 Society of Chemical Industry.

Antifungal Properties of Sargassum cinereum and Padina boergesenii Extracts Against Fungi Associated with Strawberry Fruits Concerning Mycotoxin Production.

Strawberries are susceptible to decay and destruction while being harvested and stored. This study had the following objectives: (1) the documentation of fungi and mycotoxin production associated with infected strawberry fruits; (2) the evaluation of the primary phytochemicals of Sargassum cinereum and Padina boergesenii by gas chromatography-mass spectrometry (GC-MS) and Fourier transform infrared (FT-IR) analysis to identify the active chemical composition of the seaweed extracts; and (3) the assessment of the antifungal activity of five extracts from brown seaweeds both in vitro and in vivo against fungal infections on fresh fruit under post-harvest conditions. The most common fungi were Aspergillus niger 14.36%, Botrytis cinerea 38.29%, and Mucor irregularis 16.88%. Padina boergesenii acetone extract had the highest in vitro antifungal activity. The methanol extracts of both S. cinereum and P. boergesenii were effective against the pathogenicity and aggressiveness (in vivo) on post-harvest strawberry fruits. B. cinerea could produce botrydial and dihydrobotrydial toxins with concentrations of 8.14 µg/mL and 4.26 µg/mL, respectively. A. niger could produce ochratoxin A with a concentration of 10.05 µg/mL. The present study demonstrates that the extracts of macroalgae S. cinereum and P. boergesenii contain secondary metabolites and antioxidants, indicating their potential utilization in antifungal applications.

The role of linalool in managing Alternaria alternata infection and delaying black mold rot in goji berry

Alternaria alternata, a common fungal pathogen causes black mold in postharvest goji fruit. To explore the in vitro and in vivo impacts of linalool on the fungal infection, we treated A. alternata and infected goji fruit with varying linalool concentrations (0, 0.15, 0.45, and 1.35 mL L−1). Linalool repressed hypha growth, spore yield and germination, and germ tube length of A. alternata. Furthermore, we observed abnormal spore and mycelium morphology in the treated samples using optical, scanning electron, and transmission electron microscopy. Linalool reduced lesion diameter and disease incidence in goji fruit. Moreover, transcriptomic analysis of pathogen revealed that linalool inhibited nitrogen metabolism, altered chitin and β-1,3-glucan metabolisms, downregulated the key gene expression related to ergosterol synthesis and sulfur and glutathione metabolisms, regulated the enzymatic antioxidant system, and impacted the proportion of unsaturated fatty acids. Furthermore, linalool damaged the fungal cell wall integrity by inducing alkaline phosphatase and chitinase activities and β-1,3-glucan content and repressing β-1,3-glucanase and chitin synthase activities and chitin levels. Linalool elevated superoxide dismutase and catalase activities and declined peroxidase and glutathione reductase activities and glutathione content in A. alternata, leading to increased H2O2 levels and ROS stress. Our data exhibited the promising antifungal effects of linalool with a future application in management of the postharvest rot of goji fruit.

Exogenous deferoxamine mesylate suppresses iron-dependent ferroptosis in postharvest fruit rot of blueberry caused by Alternaria alternata and Fusarium fujikuroi

Plant development relies heavily on regulated cell death, which is crucial for specific plant responses to biological stresses. Ferroptosis, an iron-dependent, oxidative, and non-apoptotic cell death form, has been recently discovered in animal cells. In this study, we investigated whether a ferroptosis-like process could be relevant to cell death in postharvest fruit rot of blueberry caused by Alternaria alternata and Fusarium fujikuroi. The results showed that deferoxamine mesylate and glutathione (GSH) treated fruit showed enhanced disease resistance with lower lesion areas, whereas an opposite result was observed in hydrogen peroxide (H2O2) treatment, indicating that intracellular ferroptosis might exist in the fungal infected blueberry fruit. Compared to control, deferoxamine mesylate or GSH treatment improved chlorophyll fluorescence parameters, which contributed to the stability of photosynthesis. In terms of ferroptosis pathway in the adjacent area of infected fruit, deferoxamine mesylate suppressed an iron-dependent cell death pathway that was characterized by depletion of H2O2 and MDA and accumulation of GSH, as well as the reduction of ferrous ions and total iron ions. Meanwhile, deferoxamine mesylate could effectively delay the decrease rate of unsaturation value and key phospholipids of fungi infected fruit during storage, which possibly maintained the integrity of cell membrane. Due to the serious rot of the lesion area, the peroxidation of membrane lipids was severe, accompanied by metabolic disorders. These combined results demonstrated that deferoxamine mesylate treatment could reduce Fenton reaction by chelating Fe2+ and avoid excessive accumulation of reactive oxygen species (ROS), suppress iron-dependent ferroptosis, thereby maintaining fruit quality and reducing postharvest diseases.

Effects of chitosan hydrolysate on control of postharvest infection caused by Botrytis cinerea and physiological responses of wounded tomato fruit

Chitosan is considered an eco-friendly plant protection agent. Chitosan hydrolysate (CH) with an average molecular weight (MW) of the main fraction of 135 × 103 Da, with a deacetylation degree (DD) of 93 % is an unfractionated product of nitric acid hydrolysis of high molecular weight chitosan. The effect of the CH on gray mold caused by Botrytis cinerea in tomato fruit stored at 25 °C was investigated. Chitosan provided effective control of B. cinerea on tomato fruit. The CH treatment of wounded tomato fruit had a protective effect, reducing the percentage of infected fruit on the 7 d after treatment to 50 %, compared with untreated wounded fruit (69 %) and water-treated fruit (88 %). The protective effect of the CH in tomato fruit may be due to a direct fungitoxic action against the pathogen. It was found that the CH induced an immune response in tomato fruit via the accumulation of phenolic compounds. The level of phenolic compounds in the CH group was higher than in the untreated wound group from day 1 to 5, with a maximum reached on day 3 (113 mg-eq GA kg-1). No significant differences were found in the activities of peroxidase, phenylalanine ammonia lyase, polyphenol oxidase, β-1,3-glucanase and chitinase. Thus, the CH affects the processes occurring during fruit damage and contributes to the preservation of the consumer qualities of fruit.

First report of Neopestalotiopsis clavispora Causing guava scab in China.

Psidium guajava L. is widely cultivated in southern China. In May 2021, guava scab on cv. Zhenzhu was observed in Zhanjiang (21.18° N, 110.21° E), Guangdong province, China. Guavascab was corky with ovoid or round lesions on the surfaces of green fruits. Gradually the lesions sunk. Disease incidence was estimated as 85% in 500 investigated plants in about 50 ha. Twenty diseased fruits were collected from twenty trees in the field. From each fruit the margin of the diseased tissues was cut into 2 mm × 2 mm pieces; surface disinfected with 75% ethanol and 2% sodium hypochlorite for 30 and 60 s, successively; and rinsed thrice with sterile water. The tissues were plated onto potato dextrose agar (PDA) medium and incubated at 28 ℃. Thirty-four isolates were obtained. Single-spore isolation method (Liu et al. 2021) was used to recover pure cultures of three isolates (PGNC-1, PGNC-2, and PGNC-3) . The colonies were initially white with cottony aerial mycelium at 7 days on PDA. Then, these colonies form black acervular conidiomata at 10 days. Conidia were clavate to fusiform, four-septate, straight or slightly curved, and measured 15.8 to 21.2 µm × 4.5 to 6.5 µm (n = 40). The three median cells were versicolored, whereas the basal and apical cells were hyaline. Conidia had a single basal appendage (4.5 to 5.5 µm long; n = 40) and three apical appendages (19.2 to 24.5 µm long; n = 40). The morphological characteristics of the isolates were consistent with the description of Neopestalotiopsisclavispora (Maharachchikumbura et al. 2012). Molecular identification was performed using PCR method with MightyAmp DNA Polymerase (Takara-Bio, Dalian, China) (Lu et al. 2012). Sequences were generated from the isolates using primers for the rDNA ITS (ITS1/ITS4), TEF1-α (EF1-728F/EF1-986R), and β-tubulin (T1/βt2b) loci (Maharachchikumbura et al. 2012). The sequences of the isolates were submitted to GenBank (ITS, OQ996557 to OQ996559; TEF, OR101037 to OR101039; β-tubulin, OR100971 to OR100973). The sequences of the isolates were 100% identical to the type strain MFLUCC12-0281 (accession nos. JX398979, JX399014, and JX399045) through BLAST analysis. The isolates clustered with N. clavispora (MFLUCC12-0280 and MFLUCC12-0281). N. clavispora and Pestalotiopsis clavispora are synonyms. The pathogenicity was tested in vivo. Plants (cv. Zhenzhu) were grown ( 3 years old) in a quarantine orchard at 25℃ to 32℃ with 60 to 80% relative humidity in May 2022. Disease-free green fruits were inoculated. Sterile cotton balls were immersed in the spore suspension (1 × 105 per mL) and sterile distilled water (control) for about 15 s before they were fixed on the wounded fruits with transparent tape. Five fruits on one plant per isolate were inoculated. Five fruits on one plant severed as control. The test was performed thrice. Disease symptoms were found on the inoculated fruits after 20 days, whereas the controls remained healthy. The pathogen was re-isolated from infected fruits and was phenotypically identical to the original isolates thus fulfilling Koch's postulates. Neopestalotiopsis or Pestalotiopsis spp. were reported to be the causal agents of guava scab in Colombia and in Hawaii (Keith et al. 2006; Solarte et al. 2018). N. clavispora has been reported to cause disease in a broad range of hosts (Ge et al. 2009; Chen et al. 2018), but not in guava. This is the first report of N. clavispora causing guava scab in China. There would be no harvest if this disease is left unmanaged.

A new brown rot disease of plum caused by Mucor xinjiangensis sp. nov. and screening of its chemical control.

A novel species of Mucor was identified as the causal agent of a brown rot of Prunus domestica (European plum), widely grown in the south of Xinjiang, China. This disease first appears as red spots after the onset of the fruits. With favorable environmental conditions, fruit with infected spots turn brown, sag, expand, wrinkle, and harden, resulting in fruit falling. Fungal species were isolated from infected fruits. A phylogenetic analysis based on internal transcribed spacer (ITS) regions and the large subunit (LSU) of the nuclear ribosomal RNA (rRNA) gene regions strongly supported that these isolates made a distinct evolutionary lineage in Mucor (Mucoromycetes, Mucoraceae) that represents a new taxonomic species, herein named as Mucor xinjiangensis. Microscopic characters confirmed that these strains were morphologically distinct from known Mucor species. The pathogenicity of M. xinjiangensis was confirmed by attaching an agar disk containing mycelium on fruits and re-isolation of the pathogen from symptomatic tissues. Later, fourteen fungicides were selected to determine the inhibitory effect on the pathogen. Further, results showed that difenoconazole had the best effect on the pathogen and the strongest toxicity with the smallest half maximal effective concentration (EC50) value, followed by a compound fungicide composed of difenoconazole with azoxystrobin, mancozeb, prochloraz with iprodione, pyraclostrobin with tebuconazole, and trifloxystrobin with tebuconazole and ethhylicin. Present study provides the basis for the prevention and control of the novel plum disease and its pathogen.

Isolation and Identification of Postharvest Rot Pathogens in Citrus × tangelo and Their Potential Inhibition with Acidic Electrolyzed Water.

This study focused on the identification of rot-causing fungi in Citrus × tangelo (tangelo) with a particular emphasis on investigating the inhibitory effects of acidic electrolyzed water on the identified pathogens. The dominant strains responsible for postharvest decay were isolated from infected tangelo fruits and characterized through morphological observation, molecular identification, and pathogenicity detection. Two strains were isolated from postharvest diseased tangelo fruits, cultured and morphologically characterized, and had their gene fragments amplified using primers ITS1 and ITS4. The results revealed the rDNA-ITS sequence of two dominant pathogens were 100% homologous with those of Penicillium citrinum and Aspergillus sydowii. These isolated fungi were confirmed to induce tangelo disease, and subsequent re-isolation validated their consistency with the inoculum. Antifungal tests demonstrated that acidic electrolyzed water (AEW) exhibited a potent inhibitory effect on P. citrinum and A. sydowii, with EC50 values of 85.4μg/mL and 60.12μg/mL, respectively. The inhibition zones of 150μg/mL AEW to 2 kinds of pathogenic fungi were over 75mm in diameter. Furthermore, treatment with AEW resulted in morphological changes such as bending and shrinking of the fungal hyphae surface. In addition, extracellular pH, conductivity, and absorbance at 260nm of the fungi hypha significantly increased post-treatment with AEW. Pathogenic morphology and IST sequencing analysis confirmed P. citrinum and A. sydowii as the primary pathogenic fungi, with their growth effectively inhibited by AEW.

In planta evaluation of different bacterial consortia for the protection of tomato plants against Alternaria spp. infection and Alternaria toxins presence in fruits

In planta evaluation of different bacterial consortia for the protection of tomato plants against Alternaria spp. infection and Alternaria toxins presence in fruits

First Report of Colletotrichum fioriniae Causing Anthracnose on Persimmon in China.

Persimmons (Diospyros kaki Thunb.) have a longstanding history of cultivation in China. Both aesthetically pleasing and edible, they often symbolize a sweet and fulfilling life. During the summer of 2022, a severe outbreak of anthracnose was observed on the lower leaves of persimmon trees in the National Field Genebank for Persimmon (NFGP), located in Yangling, Shaanxi, China (34°17'42.80″ N, 108°04'08.21″ E). The estimated incidence rate of this disease within the NFGP was approximately 30%. The typical symptoms of the disease included the presence of irregular lesions on leaves, and oval sunken lesions on infected fruit. Under high humidity conditions, pink sticky substances appeared in the affected areas. The presence of numerous lesions led to softening and detachment of persimmon fruit. To identify the causal pathogen, 5 × 5mm samples of the diseased leaves were collected from the interface between the infected and healthy leaves. The leaves were disinfected with 70% alcohol for 20 s, followed by rinsing with sterile water. Subsequently, the leaves were immersed in 1% NaClO for 2 to 3 minutes, rinsed with sterile water three times, dried using sterile absorbent paper, and the leaf samples were then transferred onto potato dextrose agar (PDA) medium, and cultured in 25°C incubators. Once the colony reached a certain size, small pieces of hyphae were extracted from edge and transferred for purification and repeated three times. After being cultured on PDA for 7 days, the colony showed a white spongy surface with a pink-orange center. The conidia displayed a fusiform shape and were transparent, measuring 4.58 to 6.53 μm × 9.27 to 13.11 μm (n=50). The isolates share morphological similarities with Colletotrichum fioriniae. The representative isolate HY-7 was selected for molecular identification. The internal transcribed spacers (ITS) region, chitin synthase (CHS-1), actin (ACT), beta-tubulin 2 (TUB2), and glyceraldehyde 3-phosphate dehydrogenase (GAPDH) gene were amplified using ITS1/4 (White et al. 1990), CHS-79F/CHS-345R (Carbone & Kohn, 1999), ACT512F/ACT (Carbone & Kohn, 1999), T1/BT2B (Glass & Donaldson 1995, O'Donnell et al., 1997), and GDF/GDR (Templeton et al. 1992), respectively. The generated sequences were deposited at GenBank under accession numbers OR878056 (ITS), OR766019 (CHS-1), OR766021(TUB2), OR766018 (ACT) and OR766020 (GAPDH). BLAST analysis revealed the sequences were 100% identical to C. fioriniae (MH865005 for ITS, JQ948953 for CHS-1, JQ949613 for ACT, JQ949943 for TUB2 and JQ948622 for GAPDH). The morphological characteristics and molecular analyses of the isolate matched the description of C. fioriniae. To fulfill Koch's postulates, the twigs and leaves of 'Fupingjianshi' in four different directions were inoculated without wounding in the field, and 10 healthy fruits were selected for wound inoculation. The concentration of conidia used for inoculation was about 1 × 106 conidia/ml, and sterilized water was used as control. The experiment was replicated three times under the same conditions. One week after inoculation, characteristic symptoms resembling those observed on the leaves of primary diseased persimmon trees appeared on the leaves and fruits. No symptoms were observed on the leaves, twigs and fruits in the control treatment. The pathogen from the artificially infected leaves and fruits were reisolated and identified as C. fiorinae based on morphological and molecular characteristics. Persimmon anthracnose is a common disease in regions where the fruit is grown, to the best of our knowledge, this is the first documented occurrence of C. fioriniae-induced anthracnose on persimmons in China, which should be paid more attentions. This report will help identify disease symptoms in the field and provides a basis for determining the occurrence, distribution, and control of C. fioriniae on persimmon leaves and fruits.

Cucurbit Leaf Crumple Virus (CuLCrV) is Seed Transmitted in Yellow Squash (Cucurbita pepo L.).

The traditional understanding of begomovirus transmission exclusively through the whitefly Bemisia tabaci (Gennadius) has shifted with findings of seed transmission in some begomoviruses over the last decade. We investigated the seed transmissibility of cucurbit leaf crumple virus (CuLCrV), a bipartite begomovirus that has recently emerged as a severe constraint for yellow squash (Cucurbita pepo L.) production in the southeastern United States. We found high concentration of CuLCrV in male and female flower tissues of infected squash, including pollen and ovules. The virus infiltrated the fruit tissues including the endocarp and funiculus, which are anatomically positioned adjacent to the seeds. In seeds, CuLCrV was detected in the endosperm and embryo where there are no vascular connections, in addition to the seed coat. The virus was detected in the radicle, plumule, cotyledonary leaves, and true leaves of seedlings grown from seeds collected from infected fruits. In the grow-out test conducted, CuLCrV infections ranged from 17-56% of the progeny plants. To ensure that partial viral genome fragments were not being mistaken for replicative forms of the virus, we performed RCA ̶ PCR and amplified complete DNA-A and DNA-B of CuLCrV from seed tissues, seedlings, progeny plants of CuLCrV infected squash. Near complete DNA-A and DNA-B sequences of CuLCrV were recovered from a progeny plant, further validating our findings. Our results demonstrate that CuLCrV can translocate from vegetative to reproductive tissues of yellow squash, persist within the seeds, and subsequently induce infection in progeny plants, confirming its capacity for seed transmission.

Characterization and Management of Post-harvest Fungal Diseases in Banana (Musa paradisiaca)

Banana (Musa spp.) is a vital crop globally, contributing significantly to food security and income generation, particularly in tropical regions like India. However, post-harvest fungal diseases pose a considerable threat to banana production, affecting both fruit quality and marketability. The current study investigated the isolation, characterization, and management of post-harvest fungal diseases in banana (Musa paradisiaca). Infected banana fruits were collected from the Dharashiv fruit market (Maharashtra, India), and pathogenic fungi were isolated and identified. Fusarium napiforme, Talaromyces atroroseus, Cladosporium cladosporioides, Fusarium sp., and Fusarium equiseti were the primary pathogens identified. DNA extraction and sequencing were employed for accurate identification, and sequences were submitted to GenBank. The antifungal activity of essential oils and plant extracts was evaluated using the Poisoned Food Technique. Essential oils from Syzygium aromaticum, Mentha piperita, and Punica granatum showed significant inhibition (P<0.05) of fungal growth, with clove and peppermint oils achieving 100% inhibition at higher concentrations. Plant extracts of Ocimum sanctum, Eucalyptus globulus, Mentha piperita, Zingiber officinale, Curcuma longa, Azadirachta indica, Piper betel, and Cymbopogon citratus were also tested, revealing notable efficacy, particularly with neem and peppermint extracts. The study that the efficacy of essential oils was more compared to aqueous plant extracts. The results suggested sustainable strategies for managing post-harvest fungal diseases in bananas and explained the importance of conducting field trials to validate laboratory results.

First Report of Fusarium fujikuroi Causing Postharvest Rot of Kiwifruit (Actinidia chinensis) in Jiangxi Province, China.

Kiwifruits (Actinidia chinensis) are among the most widely planted fruit in Jiangxi Province, China. Infected kiwifruits of the cultivars 'Hongyang' and 'Jinyan' were obtained from a commercial orchard in Fengxin county, Jiangxi Province (28°67' N; 115°42' E) from September to November 2022. The 1200 kiwifruits were collected from cold storage (cold stored for 3 months at 2°C), and moved to room temperatures (15 to 20°C), approximately 20% had symptoms of postharvest soft rot 7 days later. The infected fruits had brown or dark gray spots on the peel. Most were round or oval, with a diameter of approximately 1~3 cm. The pulp was milky white, and there was a waterlogged ring at the junction of decay. The pathogen was isolated by removing several small pieces (3×3 mm) of infected tissue from the diseased kiwifruits, which were sterilized with 75% ethanol for 30 s, dipped in 1% NaClO for 1 min, and rinsed three times with sterile distilled water. These pieces were transferred onto potato dextrose agar (PDA) and incubated for 5 days at 28°C, 75% relative humidity (RH), separated, and repurified. Eight unidentified isolates with similar morphology were obtained on PDA (D3-1 to D3-8). These isolates had abundant aerial fluffy mycelia. The colonies were white during the early stage of culture and turned light purple in the later stage. The mycelia grew 5.8 mm day-1 (n=5) on average and produced abundant conidia 10 days later. The microconidia were solitary, transparent, ovoid, with 0 to 1 septa, and 3.6 to 11.2 × 1.6 to 3.5 µm (average 6.5 × 2.9 µm, n = 50). The macroconidia were sickle-shaped, slender and slightly curved, with 3 to 5 septa, and 22.3 to 53.9 × 2.6 to 5.4 µm (average 39.5 × 4.3 µm, n = 50). Chlamydospores were absent. The morphological characteristics enabled the identification of the pathogen as Fusarium spp. (Leslie and Summerell, 2006). Isolate D3-2 was further confirmed, and the primers ITS1/ITS4 (White et al. 1990), 5F2/7CR and EF1/EF2 (O'Donnell et al. 2022) were used to amplify the internal transcribed spacer (ITS) region, RNA polymerase II largest subunit (RPB2) gene and translation elongation factor-1 alpha regions (TEF-1α). The ITS (accession no. PP077075), RPB2 (PP566653) and TEF-1α (PP566654) sequences shared 99.62 to 100% identities with ITS (ON564593.1), RPB2 (ON734380.1) and TEF-1α (ON697186.1) of F. fujikuroi from NCBI, respectively. Thus, the pathogen was identified as F. fujikuroi based on morphological and molecular characteristics. Each of the three isolates was inoculated on surface-disinfected (75% ethanol, 5 min) disease-free kiwifruits of cv. 'Jinyan' and 'Hongyang'. The six kiwifruits were pierced by a sterile inoculation needle and inoculated with 20 μl spore suspension (1×106 spores/ml), and six kiwifruits were treated with spore suspension without any wounds, four control fruits were inoculated with sterile distilled water. All the fruits were sealed in a storage box, kept at an RH of 90%-95%, and incubated at a constant temperature of 28°C for 5 days. After 3 days, the fruit rotted at the inoculation site, and after 5 days, the lesions gradually increased, and the symptoms were the same as those of the original sample. The control fruits remained disease-free. The pathogenicity tests were repeated three times. Koch's postulates were completed by reisolating the fungus from infected kiwifruits, which was identified as F. fujikuroi by sequencing. Although F. solani (Yang et al. 2018) and F. acuminatum (Wang et al. 2015) have been previously reported to rot kiwifruits in China, this is the first report of F. fujikuroi causing postharvest rot on kiwifruits in China. This discovery can alert agronomists to prevent and control this pathogen.

Effect of storage temperature on viral RNA accumulation in Plum pox virus-infected Red Lyon plum fruit from the Central Valley of Chile

Plum pox virus (PPV), the causative agent of Sharka disease, causes serious economic losses to the stone fruit industry. As PPV is not transmitted by seed, fruit from countries with Sharka present are considered low-risk for spreading the disease. However, there have been cases raising concerns about the safety of exporting fruit from countries with Sharka disease. Due to this, the generation of new scientific evidence becomes important to address these concerns. This study aimed to compare the relative accumulation of PPV viral titer between freshly harvested infected fruit with fruit subjected to cold storage, simulating transit conditions to export markets. During two consecutive seasons, the fruit was collected from a PPV-infected ’Red Lyon’ plum orchard, and divided into three treatments (T): freshly harvested fruit (T1); fruit exposed to cold (0 °C) for seven days (T2), and fruit exposed to cold (0 °C) for 15 days (T3). Semi-quantitative RT-PCR was used to estimate the viral titer; band density values obtained for products of amplification of a PPV genome fragment were normalized with the density values obtained from the constitutive gene nad5 and plotted relative to treatment T1, which served as a control for this purpose. The results showed a significant difference (p < 0.05) between T1 and other treatments. For the first season, the viral RNA reduction was of 50% in T2 and 61% in T3, compared to T1. For the second season, the corresponding RNA viral reductions were 45% in T2 and 56% in T3, compared to T1.

Quercetin alleviates difenoconazole-induced growth inhibition in carp through intestinal-brain axis

Difenoconazole (DIF) is frequently used for the management of fungal infections in fruit and vegetables and excessive residues in the aquatic environment can have adverse effects on fish such as growth inhibition. A treatment based on the dietary additive quercetin (QUE) is a promising approach to positively regulate the state of fish growth. This study focused on whether and how QUE alleviated DIF-induced growth inhibition in fish. In this study, carp were exposed to DIF (0.3906 mg/L) for consecutive 30 d, which showed growth inhibition. Disruption of the intestinal barrier led to elevated levels of intestinal lipopolysaccharide (LPS) and an inflammatory response. Through the intestinal-brain axis, LPS entered the brain where it disrupted the blood-brain barrier, triggered neuroinflammation, caused brain cell apoptosis, and damaged nerves in addition to other things. The dietary supplementation of QUE (400 mg/kg) reduced the levels of LPS in the intestinal and brain, while reducing inflammation and increasing the expression of appetite factors, thereby reducing growth inhibition in carp. This work provided evidence for QUE from the intestinal-brain axis perspective as a potential candidate for alleviating growth inhibition in fish.