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Stilbocrea banihashemiana is a recently described species of ascomycete fungi (Bionectriaceae) that causes canker and dieback diseases on fig and barberry, and dieback on loquat trees. Previous studies suggested this pathogen might affect other trees including economically important fruit crops, such as almonds, apples, and olives. This study assessed the susceptibility of 40 tree species belonging to 20 plant families, including fruit-bearing, ornamental, and edible landscape plants, to S. banihashemiana. The assessment was conducted by wound-inoculating detached shoots and one-year-old saplings with the pathogen. Based on five parameters of induced lesions, we clustered the inoculated tree species using the principal component analysis approach. The results of the approach revealed four distinct groups of tree species based on their susceptibility traits. Almond, apricot, eucalyptus, poplar, and red mulberry clustered in one group as susceptible hosts. The majority of the species examined, which included both tropical and temperate trees, were categorized as moderately susceptible. Platanus and sweet orange were identified as non-host-resistant species, while Arizona cypress, garden privet, and olive were classified as low susceptible. Moreover, our findings suggest a correlation between temperature and the aggressiveness of S. banihashemiana. This study revealed that the emerging pathogen, S. banihashemiana, could have a broader host range than currently recognized. The accidental introduction of this pathogen through the global trade of live host plants may pose a significant threat to economically important trees in temperate and subtropical regions. [ABSTRACT FROM AUTHOR]

Fungi of the Ceratocystis fimbriata complex are important pathogens in woody species, associated with symptoms of wilt, stem lesions and death of infected plants. In Eucalyptus plantations, these pathogens can reduce productivity and cause high mortality in the first years of planting. The objective of this work was to evaluate the symptoms and characterize isolates of Ceratocystis associated with Eucalyptus plantations in southern Bahia, Brazil. In this study, we observed that external symptoms manifested mainly in trees with up to 36 months of planting; however, asymptomatic diseased trees were found until the end of the cycle (7 years). Symptoms of wilt, wood discoloration, formation of adventitious shoots and bark lesions, and drying of branches and death have been observed in diseased trees. The discoloration of the wood began in the root system, which is probably the point of penetration of the causal agent. Symptoms of heartwood rot, along with the characteristic wood discoloration of Ceratocystis wilt, were observed in some of the diseased trees. Based on the sequencing of the rpbII, ms204 and bt1 gene regions, the Ceratocystis isolates obtained from diseased trees were identified as belonging to the species C. manginecans. The morphological characteristics and optimal development temperature of the studied isolates are consistent with those described in the literature for this pathogen. Although collected from geographically close locations, the Ceratocystis isolates studied exhibited different levels of aggressiveness against Eucalyptus clones. This result illustrates the difficulty in selecting materials resistant to Ceratocystis wilt. The present work improves the understanding of Ceratocystis wilt in Eucalyptus and its causal agent. [ABSTRACT FROM AUTHOR]

Abstract Bacterial canker disease caused by Clavibacter michiganensis is a substantial threat to the cultivation of tomatoes, leading to considerable economic losses and global food insecurity. Infection is characterized by white raised lesions on leaves, stem, and fruits with yellow to tan patches between veins, and marginal necrosis. Several agrochemical substances have been reported in previous studies to manage this disease but these were not ecofriendly. Thus present study was designed to control the bacterial canker disease in tomato using green fabricated silver nanoparticles (AgNps). Nanosilver particles (AgNPs) were synthesized utilizing Moringa oleifera leaf extract as a reducing and stabilizing agent. Synthesized AgNPs were characterized using UV–visible spectroscopy, scanning electron microscopy (SEM), X-ray diffraction (XRD), energy-dispersive X-ray (EDX), and Fourier transform infrared spectrometry (FTIR). FTIR showed presence of bioactive compounds in green fabricated AgNPs and UV-visible spectroscopy confirmed the surface plasmon resonance (SPR) band in the range of 350 nm to 355 nm. SEM showed the rectangular segments fused together, and XRD confirmed the crystalline nature of the synthesized AgNPs. The presence of metallic silver ions was confirmed by an EDX detector. Different concentrations (10, 20, 30, and 40 ppm) of the green fabricated AgNPs were exogenously applied on tomato before applying an inoculum of Clavibacter michigensis to record the bacterial canker disease incidence at different day intervals. The optimal concentration of AgNPs was found to be 30 µg/mg that exhibited the most favorable impact on morphological (shoot length, root length, plant fresh and dry weights, root fresh and dry weights) and physiological parameters (chlorophyll contents, membrane stability index, and relative water content) as well as biochemical parameters (proline, total soluble sugar and catalase activity). These findings indicated a noteworthy reduction in biotic stress through the increase of both enzymatic and non-enzymatic activities by the green fabricated AgNPs. This study marks a first biocompatible approach in assessing the potential of green fabricated AgNPs in enhancing the well-being of tomato plants that affected with bacterial canker and establishing an effective management strategy against Clavibacter michiganensis. This is the first study suggests that low concentration of green fabricated nanosilvers (AgNPs) from leaf extract of Moringa oleifera against Clavibacter michiganensis is a promisingly efficient and eco-friendly alternative approach for management of bacterial canker disease in tomato crop.

Bacterial canker disease caused by Clavibacter michiganensis is a substantial threat to the cultivation of tomatoes, leading to considerable economic losses and global food insecurity. Infection is characterized by white raised lesions on leaves, stem, and fruits with yellow to tan patches between veins, and marginal necrosis. Several agrochemical substances have been reported in previous studies to manage this disease but these were not ecofriendly. Thus present study was designed to control the bacterial canker disease in tomato using green fabricated silver nanoparticles (AgNps). Nanosilver particles (AgNPs) were synthesized utilizing Moringa oleifera leaf extract as a reducing and stabilizing agent. Synthesized AgNPs were characterized using UV–visible spectroscopy, scanning electron microscopy (SEM), X-ray diffraction (XRD), energy-dispersive X-ray (EDX), and Fourier transform infrared spectrometry (FTIR). FTIR showed presence of bioactive compounds in green fabricated AgNPs and UV-visible spectroscopy confirmed the surface plasmon resonance (SPR) band in the range of 350 nm to 355 nm. SEM showed the rectangular segments fused together, and XRD confirmed the crystalline nature of the synthesized AgNPs. The presence of metallic silver ions was confirmed by an EDX detector. Different concentrations (10, 20, 30, and 40 ppm) of the green fabricated AgNPs were exogenously applied on tomato before applying an inoculum of Clavibacter michigensis to record the bacterial canker disease incidence at different day intervals. The optimal concentration of AgNPs was found to be 30 µg/mg that exhibited the most favorable impact on morphological (shoot length, root length, plant fresh and dry weights, root fresh and dry weights) and physiological parameters (chlorophyll contents, membrane stability index, and relative water content) as well as biochemical parameters (proline, total soluble sugar and catalase activity). These findings indicated a noteworthy reduction in biotic stress through the increase of both enzymatic and non-enzymatic activities by the green fabricated AgNPs. This study marks a first biocompatible approach in assessing the potential of green fabricated AgNPs in enhancing the well-being of tomato plants that affected with bacterial canker and establishing an effective management strategy against Clavibacter michiganensis. This is the first study suggests that low concentration of green fabricated nanosilvers (AgNPs) from leaf extract of Moringa oleifera against Clavibacter michiganensis is a promisingly efficient and eco-friendly alternative approach for management of bacterial canker disease in tomato crop. [ABSTRACT FROM AUTHOR]

Pestalotioid fungi were isolated in pure culture from symptomatic plants of Callistemon laevis, C. viminalis, Luma apiculata (marketed as "Myrtus luma"), Myrtus communis subsp. tarentina, and M. communis var. microphylla (M. communis 'Microphylla'), showing twig canker, dieback and defoliation. The isolates were identified to species by ITS, tef1 and tub2 sequences, which revealed the presence of six species of Neopestalotiopsis (N. camelliae-oleiferae, N. hispanica, N. iberica, N. rosae, N. rosicola, and N. zakeelii) and one species of Pestalotiopsis (P. biciliata). While most species were isolated only once or twice, the majority of isolates belonged to N. rosae (13) and N. hispanica (8). Pathogenicity was investigated by pathogenicity tests on all hosts, which confirmed the pathogenicity of all Neopestalotiopsis species on at least some of the hosts tested, while P. biciliata did not cause any disease symptoms. Neopestalotiopsis hispanica and N. rosae caused symptoms in all hosts of the present study, while the other Neopestalotiopsis species tested showed no symptoms on Luma apiculata. [ABSTRACT FROM AUTHOR]

This publication is intended to guide citrus growers in distinguishing the difference between citrus canker and citrus leprosis.

Highly virulent Pseudomonas syringae pv. actinidiae biovar 3 (Psa3) causes kiwifruit bacterial canker, which seriously damages kiwifruits worldwide. We previously screened Psa3-transposon-inserted mutants and obtained reduced-virulence mutants with genes encoding the flagellar protein. Flagella are involved in the motility of bacteria and contribute to P. syringae invasion of plant leaves. However, whether flagella are required for the ability to enter stomata and then multiply in the plant apoplast is not known. Here, we sprayed kiwifruit leaves with Psa3-flagellar-defective mutants and found that their virulence was reduced compared to that of the Psa3 wild type, but their virulence was not reduced when the leaves were infiltrated with Psa3-flagellar-defective mutants using a syringe. Motility and bacterial entry into apoplastic space of the flagellar-defective mutants were also significantly reduced. These results indicate that flagella contribute to Psa3 motility and stomata-mediated entry, leading to disease development, but not multiplication in apoplast space after Psa3 entry. This study provides new insight into bacterial motility in host plants. [ABSTRACT FROM AUTHOR]

Species in the Melastomataceae (Myrtales) include trees and woody shrubs that are amongst the most common hosts of Chrysoporthe and related fungi. These fungi cause stem cankers, branch death and in extreme cases, kill their hosts. Chrysoporthe -like fungi were observed on Miconia spp. and Rhynchanthera grandiflora (Melastomataceae) plants during tree disease surveys in south-eastern Brazil including the states of Minas Gerais and Rio de Janeiro. The aims of this study were to isolate and identify the fungi utilising morphological characteristics and phylogenetic analyses. This led to the identification of a new species of Chrysoporthe described here as Chrysoporthe brasilensis sp.nov. Inoculations were conducted on R. grandiflora and M. theaezans , showing that C. brasiliensis is an aggressive pathogen. This study adds to a growing number of reports of new and pathogenic species of Chrysoporthe that potentially threaten native Myrtales globally, including important trees such as Eucalyptus , both in natural ecosystems and in planted forests. • The new species Chrysoporthe brasiliensis is pathogenic to Melastomataceae in Brazil. • Melastomataceae species are important for forest restoration. • New Chrysoporthe species are an imminent threat to eucalyptus forests. [ABSTRACT FROM AUTHOR]

Avian trichomonosis, caused by Trichomonas gallinae, a single-celled, pear-shaped protozoan, is often known as canker in doves and pigeons, and as frounce in raptors. A two-year-old Australian white pigeon presented to University Veterinary Hospital, Kokkala with a history of open mouth breathing, watery eyes, difficulty in maintaining balance for past one week. The case was diagnosed as trichomonosis based on the history, clinical signs, lesions, and identification of the organism on wetmount preparation and stained smears of samples. The bird was successfully treated with metronidazole at the dose rate of 50 mg per kg body weight orally, twice daily for seven days. [ABSTRACT FROM AUTHOR]

Field surveys were conducted in British Columbia fruit tree growing regions to determine the incidence of dieback and to identify the main fungal species causing cankers. Fruit trees showing cankers and dieback symptoms were recorded from 94% of orchards and 5.5% of trees surveyed. Overall, higher dieback incidence was observed in cherry than apple with 33% of cherry blocks showing between 5% and 26% of trees affected. Morphological studies along with DNA sequencing of the internal transcribed spacer (ITS) including the 5.8S rDNA, and parts of the translation elongation factor 1-α (TEF1), beta-tubulin (TUB2), and actin (ACT1) genes, identified seven fungi for the first time in fruit trees in Canada, including Calosphaeria pulchella, Cytospora parasitica, Cytospora populicola, Cytospora sorbicola, Ilyonectria robusta, Nectria dematiosa, and Phaeoacremonium minimum. In addition, this study reports for the first time Diplodia mutila and Diplodia seriata from cankers in sweet cherry in Canada. The already known fungal pathogens Neofabraea perennans and Neonectria ditissima were also identified. Pathogenicity studies showed N. ditissima and C. sorbicola to cause the largest vascular lesions in apple and cherry, respectively. This study identified the main fungal pathogens causing tree fruit cankers and dieback in British Columbia providing important information for the development of effective control strategies. [ABSTRACT FROM AUTHOR]

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Abstract Objectives Lasiodiplodia pseudotheobromae is an important fungal pathogen associated with die-back, canker and shoot blight in many plant hosts with a wide geographic distribution. The aim of our study was to provide high-quality genome assemblies and sequence annotation resources of L. pseudotheobromae, to facilitate future studies on the systematics, population genetics and genomics of the fungal pathogen L. pseudotheobromae. Data description High-quality genomes of five L. pseudotheobromae isolates were sequenced based on Oxford Nanopore technology (ONT) and Illumina HiSeq sequencing platform. The total size of each assembly ranged from 43 Mb to 43.86 Mb and over 11,000 protein-coding genes were predicted from each genome. The proteins of predicted genes were annotated using multiple public databases, among the annotated protein-coding genes, more than 4,300 genes were predicted as potential virulence genes by the Pathogen Host Interactions (PHI) database. Moreover, the genome comparative analysis among L. pseudotheobromae and other closely related species revealed that 7,408 gene clusters were shared among them and 152 gene clusters unique to L. pseudotheobromae. This genome and associated datasets provided here will serve as a useful resource for further analyses of this fungal pathogen species.

Objectives: Lasiodiplodia pseudotheobromae is an important fungal pathogen associated with die-back, canker and shoot blight in many plant hosts with a wide geographic distribution. The aim of our study was to provide high-quality genome assemblies and sequence annotation resources of L. pseudotheobromae, to facilitate future studies on the systematics, population genetics and genomics of the fungal pathogen L. pseudotheobromae. Data description: High-quality genomes of five L. pseudotheobromae isolates were sequenced based on Oxford Nanopore technology (ONT) and Illumina HiSeq sequencing platform. The total size of each assembly ranged from 43 Mb to 43.86 Mb and over 11,000 protein-coding genes were predicted from each genome. The proteins of predicted genes were annotated using multiple public databases, among the annotated protein-coding genes, more than 4,300 genes were predicted as potential virulence genes by the Pathogen Host Interactions (PHI) database. Moreover, the genome comparative analysis among L. pseudotheobromae and other closely related species revealed that 7,408 gene clusters were shared among them and 152 gene clusters unique to L. pseudotheobromae. This genome and associated datasets provided here will serve as a useful resource for further analyses of this fungal pathogen species. [ABSTRACT FROM AUTHOR]

In 2016, canker and severe dieback symptoms were observed on barberry (Berberis vulgaris) trees in some regions of Fars Province (Iran). Some of the affected trees were planted in vineyards, where grapevine trunk diseases had previously been studied. Therefore, to determine the potential of barberry trees to serve as inoculum reservoirs of grapevine fungal trunk pathogens, wood samples were cut and collected from infected barberry trees, and the isolation of the possible fungi were made from necrotic wood tissues on potato dextrose- agar (PDA). Fifteen fungal species, Biscogniauxia rosacearum, Botryosphaeria dothidea, Diplodia seriata, D. mutila, Dothiorella viticola, Exophiala pisciphila, Lasiodiplodia theobromae, Phaeoacremonium parasiticum, P. iranianum, P. italicum, P. cinereum, P. rubrigenum, Neoscytalidium dimidiatum, Seimatosporium vitis, and Stilbocrea banihashemiana were isolated from diseased barberry trees and identified based on morphological features and molecular data analyses. Pathogenicity tests on barberry and grapevine shoots confirmed L. theobromae to be the most aggressive species. Our study showed that barberry trees can serve as alternative tree hosts for many grapevine fungal trunk pathogens and this must be considered in the management programs of grapevine trunk diseases. [ABSTRACT FROM AUTHOR]

The angiosperm Melastomataceae family is one of the most abundant plant families worldwide and in the Brazilian cerrado, with significant environmental importance in regenerating degraded areas, especially those previously occupied by pastures. Recently, Chrysoporthe Gryzenhout & M. J. Wingf. species were reported in Brazil, causing canker, branch dieback, and mortality in native Melastomataceae. This leads to the demand for further investigation and understanding of these pathosystems. During field surveys, typical signs and symptoms associated with Chrysoporthe infection were found in Rhynchanthera grandiflora (Aubl.) D C. and Miconia theaezans (Bonpl.) Cogn. in southern Minas Gerais. Through phylogenetic analysis of the BT1 and BT2 fragments of the β‐tubulin gene and morphological characterization of the isolates obtained, it was possible to identify C. doradensis Gryzenh. & M. J. Wingf. occurring in R. grandiflora and C. puriensis M. E. S. Oliv., T. P. F. Soar. & M. A. Ferr. occurring in R. grandiflora and M. theaezans. Furthermore, pathogenicity assays confirmed the pathogenicity of both species to their hosts. [ABSTRACT FROM AUTHOR]

Plant disease is an important factor that affects the plant microbiome. However, for many plant–pathogen–microbiome interactions, the influences are unknown. Citrus, comprising abundant varieties of mandarin, sweet orange, pomelo, and lemon, is widely cultivated in different production areas in China. Most of these varieties are vulnerable to citrus canker, which is caused by Xanthomonas spp. In this study, asymptomatic and cankered leaves from asymptomatic and canker-infected trees, respectively, were collected from 17 orchards in six citrus production areas and their endophytic microbiomes were compared. The effects of canker on the microbial community richness and diversity were dependent on whether the interaction type was intrakingdom (for bacteria, positive) and interkingdom (for fungi, negative), respectively. The negative effects of canker on the fungal communities might be affected by the strong correlation between Xanthomonas and Fusarium/Gibberella species. The occurrence of canker significantly affected the composition and structure of both the endophytic fungal and bacterial communities, and altered the dominant genera of each community. In addition, canker occurrence intensified the cross-kingdom microbial interaction network, in which species of Enterobacter, Xanthomonas, Pseudomonas, and Pantoea were detected with increased roles in the network and responsible for the predominant functional genes involved in nutritional metabolism, the bacterial secretion system, and biotin metabolism. The results provide insights into the responses of the endophytic microbiome to citrus canker disease.

Nectria dematiosa exhibiting orange red colour perithecia on stems and branches of young and old apple trees were reported under field conditions during 2020 and 2021. Reddish discoloration followed by papery appearance of stem and branches were the characteristic symptoms observed. Ascomata were non‐papillate, surface irregular comprising numerous cylindrical to narrowly clavate asci. Ascospores were ellipsoidal to fusiform, straight or slightly curved, hyaline with 0 to 1‐septa. Richard and Royal Delicious variety of apple were more susceptible with moderate to high severity of the European canker. Based on nucleotide homology and phylogenetic analysis, the pathogen was confirmed as N. dematiosa (accession no. OQ152022). To the best of our knowledge, this is the first report of N. dematiosa causing European canker of apple in India. [ABSTRACT FROM AUTHOR]

Summary: During the winter of 2022, camphor trees (Cinnamomum camphora L.) showing symptoms of canker, wood discoloration and twig dieback were detected in a nursery located in Catania province of eastern Sicily, Italy. Samples were brought to the laboratory, and isolations revealed the presence of Botryosphaeriaceae spp. in symptomatic wood tissues. Representative isolates were sub-cultured and identified by sequencing. Specifically, the three loci (ITS, tef-1α, and tub2) were amplified by conventional PCR and sequenced. Phylogenetic analysis using the Maximum parsimony approach revealed that nine isolates were strongly clustered within the clade of Neofusicoccum parvum and one isolate within the clade of N. luteum. Pathogenicity tests were conducted by inoculating stems of 1-year-old camphor trees with mycelial plugs of three representative isolates of N. luteum and N. parvum. Nine days after the inoculation, the camphor trees showed the same symptoms as those observed in the nursery. To the best of our knowledge, this is the first report worldwide of N. luteum and N. parvum causing disease in camphor tree. [ABSTRACT FROM AUTHOR]

Surveys of canker diseases in 26 walnut orchards were conducted in the southeastern Turkish provinces of Batman, Diyarbakır, and Şanlıurfa in 2020. Decline symptoms on trees were most severe in the trunks of grafted trees grown on unproductive local rootstocks with Chandler and Franquette scions throughout the surveyed areas, and samples were taken from those trees. Lasiodiplodia theobromae was identified from the cankers on the trees of the seven orchards, while Neoscytalidium dimidiatum was identified from the other 19 orchards based on morphological characteristics. DNA sequencing analysis of 10 representative isolates using the ITS1-5.8S-ITS2 (ITS), the large subunit (LSU), and the translation elongation factor 1-alpha (EF-1α) genes confirmed the identification of the causal fungi. Pathogenicity tests on 2 year-old Chandler seedlings revealed that L. theobromae and N. dimidiatum produced lesion length averages of 7–8 cm and 15–25 cm after 3 weeks of stem-inoculation, respectively. Koch's postulates were confirmed by successfully reisolating the fungi only from plants inoculated. This is the first study to document L. theobromae as the causal agent of walnut tree decline and cankers in Turkey. [ABSTRACT FROM AUTHOR]

A recent survey conducted in the historical botanical garden Villa Caronia, Sicily, identified the causal organisms of branch cankers and dieback on a mature Meryta denhamii. Laboratory isolations and sequencing of three loci, namely ITS, tef1-α, and tub2, showed the presence of two species belonging to Botryosphaeriaceae, including Neofusicoccum parvum and Neoscytalidium dimidiatum. Pathogenicity tests confirmed that these species are able to induce canker symptoms on this host. To our knowledge, this is the first report, worldwide, of N. parvum and Ne. dimidiatum causing branch canker and dieback on M. denhamii. [ABSTRACT FROM AUTHOR]

Bacterial canker of stone fruit trees caused by Pseudomonas syringae pv. syringae (Pss) interacts with several factors such as ring nematodes. The effect of infection of Mesocriconema xenoplax (Mx) and Pss and co-infection in pot conditions in the greenhouse on peach bacterial canker was investigated on GN and GF677 rootstocks, tolerant and susceptible to Mx, respectively. One-year peach seedlings (cv. Zaafarani), susceptible to Pss, grafted on these rootstocks were used. Infection treatments included nematode inoculation, bacterial inoculation, and inoculation with both pathogens. The experiment was conducted as a factorial in a completely randomized design with five replications. The results were evaluated and compared statistically based on disease severity, bud death, seedling height, root weight, total plant weight, and population of Mx in soil. The results showed a significant difference between GN and GF677 in terms of response to pathogen inoculation (s) based on evaluation indexes. In both vegetative rootstocks, canker severity and dead bud in seedlings co-inoculated with Mx and Pss were more than those only inoculated with Pss alone. In seedlings with GF677 rootstock, in infection with both pathogens, the rate of canker progression up to about 30 cm was measured and dieback was observed. In inoculation with only Mx and Pss, there was a significant difference in plant growth indexes (in both treatments) and nematode population and disease severity between the two rootstocks for inoculation with nematode and bacteria. Therefore, it can be concluded that Mx is a synergistic factor for peach trees (especially at a susceptible rootstock) to aggravate bacterial canker disease caused by Pss. [ABSTRACT FROM AUTHOR]

American sycamores (Platanus occidentalis L.) are found in many ecosystems and planted in urban landscapes worldwide. The trees are highly susceptible to anthracnose and canker pathogens, causing leaf blight and branch dieback. On The Ohio State University campus in Columbus, Ohio, an American sycamore was observed to thrive among many symptomatic sycamores. The healthy tree, subsequently protected as cultivar 'Davis,' was vegetatively propagated and tested for field resistance to natural infection of canker pathogens compared to the wildtype. Incidence and severity of leaf necrosis, incidence of dieback, and tree death were evaluated for 2 consecutive seasons. The incidence of leaf necrosis was disconnected from the incidence of dieback and tree mortality, as little to no leaves were produced on the wildtype trees. By the end of the second season, 7 out of 12 wildtype trees were dead, while all 12 'Davis' trees were alive. Several canker pathogens were recovered from both 'Davis' and the wildtype, including Apiognomonia platani and Diaporthe eres. The latter had not been previously reported on American sycamore. Pathogenicity tests confirmed that D. eres is indeed pathogenic on sycamores and also that 'Davis' is significantly more resistant than wildtype to canker development and should be preferred over the wildtype in the urban landscape. [ABSTRACT FROM AUTHOR]

Canker and dieback are serious fungal diseases of woody plants that can cause huge economic losses to orchards. The purpose of this study was to classify and assess the pathogenicity of fungal species associated with canker and dieback on fruit trees growing in Henan Province, China. In total, 150 isolates of Botryosphaeriaceae were obtained from six different fruit trees exhibiting typical symptoms of stem canker, branch dieback, and gummosis. Morphological examinations and phylogenetic analysis of ITS, tefl, tub2, and rpb2 revealed two Botryosphaeriaceae species, which are Botryosphaeria dothidea and a novel species, Lasiodiplodia regiae, respectively. Using Koch's postulates, we confirmed that the different isolates of L. regiae can cause disease in their original hosts. The pathogenicity tests showed that L. regiae can cause canker, dieback, and gummosis symptoms in four different hosts, indicating a relatively wider host range. Moreover, IOC regiae isolates exhibited similar symptoms but different levels of virulence on shoots of peach trees under field conditions. This study demonstrated that L. regiae was a new causal agent of canker and dieback of six fruit tree species, which could be a serious risk to the orchard industry in China. Furthermore, the findings provide a foundation for further epidemiological studies and the development of management strategies. [ABSTRACT FROM AUTHOR]

Olive (Olea europaea L.) is a very important crop grown in the Mediterranean part of Croatia. Olive branch and fruit dieback symptoms were observed in two olive orchards in Istria, Croatia. The samples from symptomatic trees were collected and brought to the laboratory for analysis. Based on their morphological characterization, isolated fungi were identified as Cytospora sp. Two representative isolates (one per orchard) were taken for molecular analysis, and based on DNA sequence data of the ITS and TUB gene regions, and phylogenetic analysis of the sequences, the isolates were identified as Cytospora pruinosa Défago. To determine pathogenicity, pathogenicity tests were conducted on detached olive branches and two-year-old olive trees in the greenhouse. This is the first report of C. pruinosa causing olive branch and fruit dieback in Croatia. [ABSTRACT FROM AUTHOR]

Pomegranate is an economically important horticultural crop tree in tropical and subtropical countries. In 2016 and 2017, a survey of pomegranate fungal trunk pathogens was conducted in 20 orchards in Kerman and Fars provinces in Iran. Branch samples were collected from affected trees exhibiting yellowing, canker, sparse foliage, dieback, and decline. Fungal isolations were made from the margin between healthy and necrotic wood tissues on potato dextrose agar (PDA). All fungal isolates were identified based on morphological and cultural characteristics. Morphological identifications of the representative isolates were confirmed by sequence analysis of the internal transcribed spacer (ITS) nrDNA, partial β-tubulin gene (tub2), actin (act) and a partial sequence of the translation elongation factor 1α (tef-1α). In total, 285 fungal isolates were obtained from infected tissues, and the species Phaeoacremonium (P.) parasiticum, P. alvesii, P. rubrigenum, P. italicum, P. fraxinopennsylvanicum, P. inflatipes, Neoscytalidium (N.) dimidiatum, Lasiodiplodia (L.) theobromae, Diatrype (D.) whitmanensis, Kalmusia variispora, Neomicrosphaeropsis italica and Stilbocrea walteri were identified. Pathogenicity tests were conducted on pomegranate shoots, and the length, width and depth of the wood lesions caused by inoculated isolates were assessed 40 days after inoculation. The lesions caused by L. theobromae were significantly longer (F = 4.29, P < 0.0012) than those caused by other species while, N. dimidiatum caused wider (F = 6.27, P < 0.0001) and deeper (F = 5.18, P < 0.0003) wood lesions compared to other tested species. This study represents the first record of P. alvesii, P. rubrigenum, P. fraxinopennsylvanicum, P. inflatipes, D. whitmanensis, K. variispora, N. italica and S. walteri on pomegranate trees worldwide and the first report of N. italica in Iran. [ABSTRACT FROM AUTHOR]

Cytospora is a genus of fungi belonging to the Cytosporaceae family (Sordariomycetes, Ascomycota) considered as a prolific source of specialized metabolites due to their ability to produce diverse secondary metabolites with a broad range of biological activities. Since the first chemical investigation of this genus in the 1980s, further studies have led to the isolation and structural elucidation of several bioactive compounds including cytosporones, nonanolides, macrocyclic dilactones, and terpenoids. This review summarizes, for the first time, the chemical diversity of bioactive secondary metabolites from the genus Cytospora and highlights its potential as an alternative source of secondary metabolites for pharmacological studies. Moreover, this review will serve as a basis for future investigations of compounds of this genus. [ABSTRACT FROM AUTHOR]

For about a decade, olive groves in Apulia (Southern Italy) have been progressively destroyed by Olive Quick Decline Syndrome (OQDS), a disease caused by the bacterium Xylella fastidiosa subsp. pauca (Xfp). Recently, we described an additional wilting syndrome affecting olive trees in that area. The botryosphaeriaceous fungus Neofusicoccum mediterraneum was found associated with the diseased trees, and its high virulence toward olive trees was demonstrated. Given the common features with Branch and Twig Dieback (BTD) of olive tree, occurring in Spain and California, we suggested that the observed syndrome was BTD. During our first survey, we also found a botryosphaeriaceous species other than N. mediterraneum. In the present article, we report the morphological and molecular characterization of this fungal species which we identified as Neofusicoccum stellenboschiana. In the study, we also included for comparison additional N. stellenboschiana isolates obtained from olive trees in Latium and Tuscany region (Central Italy). The occurrence of N. stellenboschiana in olive trees is reported here for the first time in the northern hemisphere. The pathogenicity and virulence were tested in nine inoculation trials, where the Apulian N. stellenboschiana isolate was compared with the isolate from Latium and with the Apulian isolate of N. mediterraneum. Both isolates of N. stellenboschiana proved pathogenic to olive trees. They caused evident bark canker and wood discolouration when inoculated at the base of the stem of two/three-year-old trees and on one-year-old twigs. However, virulence of N. stellenboschiana was significantly lower, though still remarkable, compared with N. mediterraneum in term of necrosis progression in the bark and the wood and capacity of wilting the twigs. Virulence of N. stellenboschiana and N. mediterraneum did not substantially change when inoculations were performed in spring/summer and in autumn, suggesting that these fungal species have the potential to infect and damage olive trees in all seasons. The high thermotolerance of N. stellenboschiana was also revealed with in vitro growth and survival tests. The high virulence of these Botryosphaeriaceae species highlights their contribution in BTD aetiology and the necessity to investigate right away their diffusion and, possibly, the role of additional factors other than Xfp in the general decline of olive groves in Apulia. Hence the importance of assessing the degree of overlap of BTD/Botryosphariaceae with OQDS/Xfp is discussed. [ABSTRACT FROM AUTHOR]

Fungi of the family Botryosphaeriaceae are considered responsible for various symptoms in avocado such as dieback, external necrosis of branches and inflorescences, cankers on branches and trunks, or stem-end rot of fruits. In recent years, these problems are becoming more frequent in avocado orchards in the Canary Islands (Spain). This work includes the characterization of fungal species involved in these diseases, which were isolated from avocado crops in Tenerife Island between 2018 and 2022. A total of 158 vegetal samples were collected, from which 297 fungal isolates were culture-isolated. Fifty-two of them were selected according to their morphological features as representative isolates of Botryosphaeriaceae, and their molecular characterization was carried out, sequencing the ITS1-2 region as well as the β-tubulin and the elongation factor 1-alpha genes. Five species of Botryosphaeriaceae were isolated, including Neofusicoccum australe, N. cryptoaustrale/stellenboschiana, N. luteum, N. parvum, and Lasiodiplodia brasiliensis. This is the first time that L. brasiliensis has been associated with avocado dieback and that N. cryptoaustrale/stellenboschiana has been cited in avocado causing symptoms of dieback and stem-end rot. However, it was not possible to assign our isolates unequivocally to N. cryptoaustrale or N. stellenboschiana even additionally using the rpb2 marker for their molecular characterization. Botryosphaeriaceae family seem to be involved in avocado dieback, in the premature fall of fruits during their development in the field and in post-harvest damage in Tenerife, but further studies are needed to clarify the fungal pathogens associated with symptoms in relation to phenological plant growth stages or less frequently observed. [ABSTRACT FROM AUTHOR]

In June, 2021, laurel willow (Salix pentandra) near Slave Lake, Alberta, was found to be infected by a Melampsora sp. that produced bright yellow urediniospores in uredia that were present on catkins, leaves, and stems. All Melampsora species previously reported in Canada are recorded as infecting leaves; therefore, further investigation was undertaken to ascertain the identity of this pathogen. To assess the relationship between this specimen and other Melampsora spp. previously collected from Canada, samples of willow leaves infected by Melampsora spp. were sourced from mycological herbariums located at the Laurentian Forestry Centre (QFB) and the Northern Forestry Centre (CFB, WINF(M)). DNA sequence data from the internal transcribed spacer (ITS) ribosomal RNA region of the fresh specimen, herbarium specimens, and DNA sequence data deposited within GenBank, were used to conduct a phylogenetic analysis. Sequencing and BLAST analysis of the material from the sample resulted in a 99.3% sequence identity match to Melampsora epitea “Mel J” collected from Larix laricina in New York State. The ITS sequence from the herbarium sample WINF(M)7356 (described as M. abieti-capraearum from Manitoba) had 100.0% identity with the Alberta sample. Additionally, specimens WINF(M)11892 (Melampsora sp. from Manitoba) and CFB8931 (Melampsora sp. from the Yukon) had 99.0% sequence identity with the Alberta sample. From these results we applied the identity of M. epitea to the rust discovered in Slave Lake, AB. With the current emphasis on willows for bioenergy production in Canada, growers must remain vigilant for this pathogen and the damages it could cause to willow plantations.

During 2020–2021, cultivated red-fleshed dragon fruit (Hylocereus polyrhizus) in Phatthalung province, southern Thailand, was infected with canker disease in all stages of growth. Small, circular, sunken, orange cankers first developed on the cladodes of H. polyrhizus and later expanded and became gray scabs with masses of pycnidia. The fungi were isolated using the tissue transplanting method and identified based on the growth of the fungal colony, and the dimensions of the conidia were measured. Their species level was confirmed with the molecular study of multiple DNA sequences, and their pathogenicity was tested using the agar plug method. Morphological characterization and molecular identification of the internal transcribed spacer (ITS), translation elongation factor 1-α (tef1-α) and β-tubulin (tub) sequences revealed the fungal pathogen to be a new species. It was named Neoscytalidium hylocereum sp. nov. The biota of the new species, N. hylocereum, was deposited in Mycobank, and the species was assigned accession number 838004. The pathogenicity test was performed to fulfil Koch's postulates. N. hylocereum showed sunken orange cankers with a mass of conidia similar to those observed in the field. To our knowledge, this is the first report of H. polyrhizus as a host of the new species N. hylocereum causing stem cankers in Thailand. [ABSTRACT FROM AUTHOR]

Gnomoniopsis castaneae is an important, destructive pathogen of Castanea species, initially identified as the primary agent of nut rot in Europe and Oceania. Although a decade of research has focused almost exclusively on its association with and activity in chestnuts, it has been identified as a mild pathogen or endophyte in multiple other hardwood species, whose roles as potential reservoirs and hosts have remained unexplored. Although the origin of the disease is unknown, it is thought to be a ubiquitous endophyte that has potentially shifted to pathogenic activity as a result of global climate change. Yet there is evidence of the expansion of the range of the pathogen as it continues to be identified in new regions, suggesting some degree of introduction is occurring. Its recent discovery in the United States brings a new urgency to the need to understand the full range and epidemiology of G. castaneae and to examine potential methods of detection and mitigation. [ABSTRACT FROM AUTHOR]

Cinnamon is a tree introduced to the lowlands of Mexico in the mid-16th century, but it spread to other places at the beginning of the 20th century due to its important commercial value as an aromatic spice. In the state of Veracruz, symptoms of dieback have been observed in 12-year-old cinnamon plantations cultivated in an agroforestry system, causing concern among producers. For this reason, the present investigation was carried out to determine the causal agent of these symptoms observed in cinnamon trees. Fifty symptomatic plants were recovered from established plantations. One hundred cinnamon root fragments showing dieback were selected and separated; isolates were made from tissue showing crown and root rot on clarified juice V-8 agar medium. After eight days, the growth of whitish coralloid mycelium with characteristics similar to the Phytophthora oomycete was consistently observed. Subsequently, the identity corresponding to P. cinnamomi was confirmed by morphological, taxonomic studies and Bayesian inference of the rDNA internal transcribed spacer. The pathogenicity test was performed on 20 6-month-old cinnamon plants grown in pots by inoculating 2.5 × 104/mL of zoospores around the roots. Control plants were inoculated with sterile distilled water and kept in a greenhouse under conditions controlled. After five weeks, symptoms of root rot were observed in the inoculated plants; however, the control group plants remained healthy. The results showed that P. cinnamomi subclade 7c was responsible for the symptoms observed in lowland cinnamon plantations in Mexico. Our findings suggest that this phytopathogen is a new threat for cinnamon growers; likewise, it is recommended that growers implement management strategies to avoid its introduction into nurseries or new plantations that could be susceptible to this pathogen. [ABSTRACT FROM AUTHOR]

Canker symptoms were observed on almond trees in the Fez-Meknes region, Morocco. Isolations were conducted from the infected branch and trunk showing internal and external brown lesions. Four representative fungal isolates were screened, and their identities were confirmed by cultural traits and sequence analysis of DNA using two genes, the ITS region (internal transcribed spacer) and calmodulin (cmdA). The identified fungi were Curvularia hawaiiensis, Fusarium ambrosium, Lasiodiplodia theobromae, and Chondrestereum purpureum. The pathogenicity test on almond twigs revealed that these species were pathogenic to their host with different degrees of virulence, with Lasiodiplodia theobromae as the most virulent causing the longest necrotic lesion (285.17 mm) and the death of twigs. Physiological traits analysis of the above-mentioned fungi showed that the optimum mycelium growth response at different temperatures varies from 10 to 35 °C, while the pH ranges between 3.0 and 8.0. This study confirms the presence of canker pathogens on almond trees, which will contribute valuable information to improve the understanding of the contemporary status of almond trees, thus helping the improvement of the management of almond orchards. To our knowledge, all these fungi represent new records in Morocco and some of them are confirmed on the almond trees for the first time in the world. [ABSTRACT FROM AUTHOR]

Historical results from provenance trials tended to position Sudetan larch (Larix decidua Mill. sudetica) populations among the least susceptible to larch canker (Lachnellula willkommi (R.Hartig) Dennis), in sharp contrast to Alpine populations. However, a recent large-scale outbreak of larch canker in artificial French stands planted with Sudetan larch brings into question this conclusion but also, as a consequence, the value of Sudetan larch seed orchards to mass-propagate risk-limited forest reproductive material. Clonal material from the French breeding population and seed orchards was investigated for its susceptibility to larch canker. As a first step, a genetic structure analysis of this population (220 clones) was conducted: it revealed its genetic heterogeneity, with 53.1% of the clones classified as "pure" Sudetan, 3.1% as Alpine; 1.5% as Central European and 42.3% as introgressed. Following artificial inoculation, "pure" Sudetan clones appeared generally less susceptible to canker than Alpine clones; admixed clones behaved in a similar way to the pure Sudetan material. However, the broad clonal variability observed within each population prevents the sole use of genetic origin of clones to rogue the most susceptible ones within orchards. Artificial inoculation is, so far, the only reliable way to properly assess clonal behaviour towards canker and thus support genetic roguing of orchards. [ABSTRACT FROM AUTHOR]

Trichomonas gallinae is a protozoan parasite that causes canker in pigeons. Squabs (young pigeons) are frequently infected with T. gallinae and can die because of the infection, while adult pigeons can act as carriers showing no clinical signs. In the present study, 50 squabs, up to 1-month-old, were purchased from pigeon markets in different regions of the Giza governorate, Egypt. Direct wet mount preparations of the oral excretions of the squabs (mouth wash) and Giemsa staining revealed that 64% (32/50) were positive for T. gallinae. Experimental infection of ten squabs with 103 T. gallinae trophozoites/ml resulted in oral lesions on the mouth, tongue, and soft palate, with the presence of yellowish-white nodules (cheese-like) in the oral cavity on the sixth day post-infection in all squabs. A subset of five samples were cultured in modified Diamond's media, their DNA was extracted, and a portion of the ribosomal internal transcribed spacer region (ITS1/5.8S/ITS2) was amplified by polymerase chain reaction (PCR) followed by sequencing. Phylogenetic analysis of the five isolates revealed 64–91% homology with some reference isolates circulating in Egypt and related countries. [ABSTRACT FROM AUTHOR]

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Forest trees withering is an increasingly ubiquitous phenomenon throughout the Mediterranean basin. Aleppo pine (Pinus halepensis Mill.) is one of the dominant conifer species in this region. In the northeastern pine coastal woodland of Tunisia, Pinus halepensis stands originally afforested to stabilize sand dunes are often damaged. Fungal pathogens are among the main causes of forest tree diseases. Species of the Botryosphaeriaceae family, having a worldwide distribution, are well known as plant pathogens including Pinus spp. Pinus halepensis trees are suffering from shoot dieback, branch cankers and trunk cankers in two Tunisian forests. The objective of the present work was to characterize Botryosphaeriaceae species associated with P. halepensis branch canker in Bizerte (Rimel forest). A total of 43 isolates were obtained from infected branches of P. halepensis trees. Using morphological characteristics and phylogenetic analysis, two Botryosphaeriaceae species were identified, that is Diplodia scrobiculata and Neofusicoccum luteum. Pathogenicity tests were performed on 3‐year‐old P. halepensis plants and both isolates were found to be pathogenic. Diplodia scrobiculata was the more virulent species had a greater virulence than Neofusicoccum luteum based on the length of vascular necrosis in the wood of the P. halepensis inoculated stem. To our knowledge, this is the first record of Neofusicoccum luteum and Diplodia scrobiculata associated with P. halepensis branch canker and dieback in Tunisia and worldwide. [ABSTRACT FROM AUTHOR]

Stem diseases of soybean with symptoms typical of infection by Diaporthe spp. are common in the Northern USA. Information is limited, however, on the characteristics of the associated pathogens. This study determined the identity and characteristics of Diaporthe spp. associated with symptomatic and asymptomatic soybean stems across diverse environments in Minnesota. Plants with symptoms of stem canker, pod and stem blight, and plant dieback, as well as asymptomatic plants, were sampled. Agar-based media and PCR assays were used to isolate and detect Diaporthe spp. from stems. The isolates were identified to species based on DNA sequencing and morphology. Diaporthe spp. were common in symptomatic and asymptomatic plants across all environments. Three species were detected: D. longicolla, D. caulivora, and D. cucurbitae. Diaporthe longicolla was the most widespread in distribution. Diaporthe cucurbitae was isolated from symptomatic soybean and confirmed to be a soybean pathogen for the first time. Only D. longicolla was detected in asymptomatic plants. While all isolates were pathogenic to soybean, virulence differed among isolates, and cultivars differed in susceptibility. Temperatures of 25°C and 32°C differentially influenced the growth of D. longicolla and D. caulivora. All isolates were sensitive to pyraclostrobin and tebuconazol. The results advance our understanding of the Diaporthe species associated with different soybean stem diseases, as well as their characteristics and management. [ABSTRACT FROM AUTHOR]

The importance of the citrus crops is recognized throughout the world. Despite tremendous advancements in agricultural technology, citrus fruit production is still considered a significant challenge. Various biotic factors have trampled down the production rate of Citrus in many places. Among them, canker caused by Xanthomonas axonopodis pv. citri (Xac) and Xanthomonas citri pv. citri (Xcc) is of great importance. Infection caused by Xac leads to lesion development in leaves, fruits, and stem. Defoliation and early fruit drop can occur as a result of severe infection, resulting in a loss of fruit output. Preliminary management techniques involve quarantining and sanitizing. Chemical copper-based bactericides are frequently employed in places with large-scale production. However, the continued use of chemicals, on the other hand, has led to the evolution of resistant microorganisms and increased the rate of soil pollution. Various alternative strategies have been suggested to address this issue. This review will go over the advances in biocontrol agents that have been used to combat the disease. [ABSTRACT FROM AUTHOR]

Ceratocystis wilt disease has caused significant mortality in duku (Lansium domesticum) since 2014 and has now spread to all districts in South Sumatra, Indonesia. Recently, 16 isolates from duku representing populations from various districts in South Sumatra were isolated. Analysis for the morphological characteristic of the isolate showed that the population has a uniform morphology. Genetic analysis based on internal transcribed spacer (ITS) and β-tubulin sequences verified that the population has being dominated by the ITS5 haplotype of Ceratocystis fimbriata and a new ITS group, the ITS7b haplotype that was localized in Musi Banyuasin. Both haplotypes were highly pathogenic to duku. Inoculation tests on various forest and agroforestry plant hosts showed that both haplotypes were highly pathogenic to Acacia mangium, moderately pathogenic to Acacia carsicarpa, Eucalyptus urophylla, and Melaleuca cajuputi, but weakly pathogenic to Dyera costulata, Hevea brasiliensis, and Alstonia scholaris. Therefore, this pathogen becomes a serious threat to Indonesia’s biodiversity due to its ability to infect forest and agroforestry plants, especially the indigenous ones.

Persian walnut (Juglans regia L.), a globally significant and economically important tree, is cultivated worldwide for its valuable wood and nutritious nuts. In this study, we conducted a comprehensive survey of the trees exhibiting signs of distress, such as trunk and branch cankers, dieback, and wood discoloration, in the central region of Fars Province in Iran. Initial morphological identification indicated that the fungal isolates recovered from the canker symptoms belonged to a newly emerged ascomycete pathogen, Stilbocrea banihashemiana. The identification was further confirmed by utilizing species-specific primer pairs for S. banihashemiana. Pathogenicity assessments on detached shoots and one-year-old saplings revealed the isolates' ability to induce wood necrosis symptoms. The cross-pathogenicity test with isolates of S. banihashemiana from walnut and other reported hosts, including fig, loquat, and pomegranate was performed on detached branches. The results indicated varying levels of aggressiveness of the isolates across the different host species examined. To our knowledge, this is the first global confirmation of the isolation of S. banihashemiana from infected Persian walnut trees and the assessment of its pathogenicity on this new host. • We conducted a survey on distressed Persian walnut trees in Fars Province, Iran. • Stilbocrea banihashemiana was Identified as the canker-causing pathogen. • We demonstrated the pathogen's ability to induce wood necrosis symptoms on the host. • Cross-pathogenicity tests showed varying levels of aggressiveness on natural hosts. • This is the first report of S. banihashemiana associated with walnut canker. [ABSTRACT FROM AUTHOR]

Walnut (Juglans regia L.) is one of the main nutritional nut crops in many parts of the world. Iran is one of the most important countries in the world regarding walnut production. In recent years, dieback and decline of some of walnut trees has attracted the attention of growers and plant pathologists in Iran. Although the infestation by the Cytospora spp. was accepted as the causal agent of canker, dieback, and decline in walnut trees, the role of the other agents has yet to be well investigated. Field observations were conducted during 2016- 2020 from different provinces in Iran, and black sooty canker was noticed in most declined or declining walnut trees. To determine the causal agent of the observed symptoms, sampling was conducted, and fungal isolates were obtained from symptomatic tissues of walnut trees. The fungus consistently isolated was identified as Neoscytalidium dimidiatum based on morphological and molecular characteristics of the ITS and tef1-α regions. Neoscytalidium dimidiatum was shown to be the cause of the symptoms by pathogenicity testing. The current findings show that N. dimidiatum is a serious and devastating disease in Iran, causing walnut tree decline.

Three Botryosphaeriaceae species, not previously recorded on coast redwood, were detected from native redwood stands in Humboldt Co., CA during general surveys between 2014 and 2017. Pathogenicity experiments with three of these fungi, Diplodia scrobiculata, Diplodia mutila, and Dothiorella californica, were performed on 2‐year‐old redwood seedlings to fulfil Koch's postulates and prove pathogenicity. Only D. scrobiculata produced lesions significantly longer than control lesions, although they were generally smaller than those of more virulent Botryosphaeriaceae pathogens in previous studies. In a separate pathogenicity study of D. scrobiculata on younger seedlings without secondary growth, inoculations on wounded stems resulted in black lesions that were much more externally obvious than the wound inoculations on lignified stems after 90 days. However, no lesions developed on non‐wounded stems of younger seedlings. Lesion lengths caused by D. scrobiculata were consistent between the two studies. On one wound‐inoculated, non‐woody seedling, D. scrobiculata was recovered from asymptomatic stem tissue 2 cm below the inoculation site, indicating possible pathogen latency. These experiments indicate that there are more Botryosphaeriaceae fungi involved in coast redwood dieback than previously known and confirm the pathogenicity of D. scrobiculata on primary and secondary tissue of coast redwood. [ABSTRACT FROM AUTHOR]

Kinnow has been a high profit earning commodity throughout the whole world for many years. But the current situation is not satisfactory for export of Kinnow, as only 2.6% of Kinnow export is being done in developed countries. Most of the Pakistani production Kinnow is being exported to Middle East countries, Iran, Afghanistan, Philippines, Indonesia, Malaysia, Vietnam, Russia etc. One of major reasons for decreased export is losses occurred in result of various infections and lowered cosmetic quality during postharvest period. Kinnow is perishable in nature and easy peel-able soft fruit which require special care and management during production and postharvest period. The aim of this study was to investigate root causes of these problems during post-harvest chain and their management strategies, observing the preventive management strategies would help to avoid postharvest losses of citrus crop occurring through various defects, disorders and diseases. Postharvest management techniques and strategies are applied to Kinnow for extension of shelf life, freshness and appearance ultimately reducing postharvest fruit losses. Approximately, one third crop losses can be minimized through appropriate handling and management during harvesting, grading, sorting, packing, storage and transportation. Proper management of diseases, disorders and blemishes on the scientific basis can improve quality and value of the produce minimizing the losses. Infection causing pathogens in citrus fruit like Kinnow mandarin can be grouped as wound pathogens and latent pathogens waiting for suitable conditions to be active. Apart from the diseases, citrus is also vulnerable to various rind disorders and defects adversely affecting the cosmetic outlook and ultimately market acceptability. Preventive management strategies include maintenance of tree vigor, tree pruning, skirting, orchard sanitation, caring for fruit quality, observing fruit maturity standards, harvesting, packing and postharvest handling through best postharvest management practices. Observing the preventive management strategies would help to avoid postharvest losses of citrus crop occurring through various defects, disorders and diseases. [ABSTRACT FROM AUTHOR]