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Pseudocercospora pistacina (CBS 135840). A. Fruit tree orchard. B–c. Leaf spots. d. Disease symptoms on fruit. e. Conidia cirrhi oozing from immersed pycnidial conidiomata. F–g. Vertical section through pycnidia. h. Conidiogenous cells giving rise to conidia. I. Conidia.
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Several species of Septoria are associated with leaf and fruit spot of pistachio (Pistacia vera), though their identity has always been confused, making identification problematic. The present study elucidates the taxonomy of the Septoria spp. associated with pistachio, and distinguishes four species associated with this host genus. Partial nucleot...
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DNA barcoding is a rapid diagnostic approach in which short DNA sequences (ca. 600 bp) – the DNA barcodes – are used for species identification. Ideally, barcodes are sufficiently variable to distinguish closely related species and are flanked by conserved regions to allow the use of group-specific primers. Fungi play pivotal roles in ecosystems an...
Citations
... Septoria pistaciarum infects leaves, shoots, and nuts of pistachio trees, causing a variety of symptoms, including leaf spots, shoot blight, and nut rot (Crous et al., 2013) and can significantly reduce pistachio quality and yield (Drais et al., 2023). In leaves the symptoms of the disease appear on both sides from spring until the end of summer, where the pathogen produces conidia from pycnidial conidiomata that dispersed initiating new infections (Gusella et al., 2021). ...
... The host range of S. pistaciarum appears to be limited to pistachio trees, but the pathogen can survive in infected plant debris on the ground, in fallen leaves, or infected nursery stock (Chitzandis, 1956). Although other closely related species of the Mycosphaerellaceae also infect pistachio, S. pistaciarum is morphologically distinctive with angular leafspots confined by leafveins (Crous et al., 2013). Spread can occur by wind-blown spores which can disperse in long distances (Gusella et al., 2021), or by contact with infected plant material (Chitzandis, 1956). ...
... A previous phylogenetic study based on 5 conserved loci-which distinguished S. pistaciarum from other pistachio-infecting Mycosphaerellaceae spp. (Crous et al., 2013)-amounts to the current extent of genomic study of this organism. This study represents the first analysis of the pan-genome of a local Mediterranean population of S. pistaciarum. ...
Septoria pistaciarum, a causal agent of Septoria leaf spot disease of pistachio, is a fungal pathogen that causes substantial losses in the cultivation, worldwide. This study describes the first pan-genome-based survey of this phytopathogen—comprising a total of 27 isolates, with 9 isolates each from 3 regional units of Greece (Pieria, Larissa and Fthiotida). The reference isolate (SPF8) assembled into a total of 43.1 Mb, with 38.6% contained within AT-rich regions of approximately 37.5% G:C. The genomes of the 27 isolates exhibited on average 42% gene-coding and 20% repetitive regions. The genomes of isolates from the southern Fthiotida region appeared to more diverged from each other than the other regions based on SNP-derived trees, and also contained isolates similar to both the Pieria and Larissa regions. In contrast, isolates of the Pieria and Larissa were less diverse and distinct from one another. Asexual reproduction appeared to be typical, with no MAT1-2 locus detected in any isolate. Genome-based prediction of infection mode indicated hemibiotrophic and saprotrophic adaptations, consistent with its long latent phase. Gene prediction and orthology clustering generated a pan-genome-wide gene set of 21,174 loci. A total of 59 ortholog groups were predicted to contain candidate effector proteins, with 36 (61%) of these either having homologs to known effectors from other species or could be assigned predicted functions from matches to conserved domains. Overall, effector prediction suggests that S. pistaciarum employs a combination of defensive effectors with roles in suppression of host defenses, and offensive effectors with a range of cytotoxic activities. Some effector-like ortholog groups presented as divergent versions of the same protein, suggesting region-specific adaptations may have occurred. These findings provide insights and future research directions in uncovering the pathogenesis and population dynamics of S. pistaciarum toward the efficient management of Septoria leaf spot of pistachio.
... Septoria leaf spot is considered the most widespread leaf disease of pistachio around the world. The taxonomic re-classification conducted by Crous et al. [15] helped to elucidate the classification of this group of pathogens, now accommodated within three genera, including Cylindroseptoria, Pseudocercospora and Septoria s.str. In Sicily, the isolates recently collected and characterized by Gusella et al., [16] clustered within the group of S. pistaciarum, confirming the first description made by Caracciolo [14]. ...
Septoria leaf spot is one of the most widespread diseases affecting pistachio (Pistacia vera) in countries of the Mediterranean region. Septoria pistaciarum was recently confirmed as the causal agent of this disease in Italy. Currently, the detection of S. pistaciarum relies on isolation techniques. These require significant amounts of labor, and time for completion. Also, a reliable identification requires the sequencing of at least two housekeeping genes, in addition to the morphological observations. To accurately detect the presence and quantify S. pistaciarum in pistachio tissues, a molecular tool was necessary. We designed applicable primers that allow reliable amplification of the β-tubulin gene. The amplification of target DNA was highly efficient, with a 100% success rate, and the assay was able to detect as little as 100 fg/rxn of pure fungal DNA. When tested in artificial mixtures of plant and pathogen DNAs, the assay was able to detect the pathogen consistently at a limit of detection of 1 pg/rxn. The assay was also effective in identifying the pathogen in naturally infected samples, providing rapid detection in all symptomatic specimens. The resulting qPCR assay is an improved detection tool for accurate diagnosis of S. pistaciarum that can also contribute to better understand the population dynamics of the pathogen in the orchard.
... At the same time, measures to combat certain diseases of the pistachio plant were also recommended. Studies on the taxonomy of 4 species of the fungus Septoria spp., which causes septoria pistaciae were also conducted in Spain [8]. During the research, S. pistaciarum and S. pistachina species belonging to the Septoria family were isolated from the genes of fungal isolates that cause leaf spot disease in different areas where the pistachio plant grows. ...
This article introduces the results of research on the harmful effects of septoria, a fungal plant pathogen infecting pistachio, on pistachio fruit weight and yield. In recent years, there has been an increase in the negative effects of various diseases on the pistachio crop. Therefore, maintaining their yield and developing modern disease control measures remains one of our main goals. The measures to combat this disease and the effectiveness of the most suitable chemical preparations are presented below.
... Several fungal pathogens have been reported from pistachio cultivation that caused blossom/panicle and shoot blight, late blight, powdery mildew, fruit and leaf spot and other disease symptoms (Dinc, 1983;Michailides et al., 1995;Crous et al., 2013). Moreover, numerous diseases including Root rots, Phytophthora foot rot, Verticillium wilt, Eutypa dieback, Wood decay, Rust, Camarosporium blight, Stigmatomycosis, and Septoria leaf spot were reported on pistachio in Greece (Chitzanidis, 1995). ...
... -138 -morphologic features and the pathogen is distinguished by conidia size. In the previous studies, the pathogen was identified incorrectly therefore a recent study conducted by Crous et al. (2013) shows that Septoria-like pathogens along with pistachio are classified into molecularly three genera including, Cylindseptoria, Septoria and Pseudocercospora. The aim of the current study is to explain the Septoria species causing leaf and fruit spot diseases in pistachio (Pistacia. ...
... The lesion sizes are coalescing to form larger spots and scatter on the infected tissue in the advanced stages. Later, numerous pycnidia develop within these lesions surrounded by a distinct margin (Crous et al., 2013). Morphologic characters of the pathogen are given in Table 2. ...
... Several countries reported the presence of these species associated with pistachio, in particular, S. pistaciarum in Arizona, New Mexico (US), Greece, India, Italy, Spain, and in East-Mediterranean and Southeast Anatolian regions (Ahmad et al., 2011;Caracciolo, 1934;Eskalen et al., 2001;French et al., 2009;L opez-Moral et al., 2021;Sarejanni, 1935;Young and Michailides, 1989), S. pistaciae in the United States (California), Italy, Greece, Ukraine and Egypt (Dudka et al., 2004;Haggag et al., 2006;Michailides, 1991;Montemartini, 1931;Pantidou 1973;Pupillo and Di Caro, 1952); and S. pistacina in Greece, Syria and Iran (Aghajani et al., 2009;Chitzanidis, 1956;Spaulding, 1961). Recently, Crous et al. (2013) elucidated the taxonomy of Septoria-like pathogens associated with pistachio, revealing three genera associated with this host, specifically Cylindroseptoria, Pseudocercospora and Septoria s. str. Until now, no molecular data from Italy confirmed the identity of Septoria spp. ...
... Conidia were hyaline, curved to falcate, showing 1 to 5 septa ( Fig. 4d and e). Measurements results, summarized in Table 2, were compared to the taxonomic key provided by Crous et al. (2013). ...
... Although other authors reported S. pistaciarum worldwide (Ahmad et al., 2011;Eskalen et al., 2001;Mass et al., 1971;Young and Michailides, 1989) no molecular data were provided, but identification was done based on only morphological observations and conidia size measurements. For the first time, a study conducted by Crous et al. (2013) elucidated the taxonomic status of septoria-like pathogens associated with pistachio, revealing new taxa classification on the basis of a multi-locus phylogenetic analysis. Results from the study of Crous et al. (2013) led to distinguish Cylindroseptoria pistaciae, Pseudocercospora pistacina (ex S. pistacina), Septoria pistaciae and S. pistaciarum. ...
Septoria leaf spot is one the most widespread disease affecting pistachio (Pistacia vera) in countries of the Mediterranean region. Traditionally, three species have been associated with pistachio, including Septoria pistaciae, Septoria pistaciarum and S. pistacina. However, recent taxonomic studies have reordered and clarified the status of Septoria and septoria-like pathogens affecting pistachio. In our study, field surveys conducted in the traditional Sicilian pistachio production area of Bronte revealed the presence of trees showing characteristic septoria-like leaf spot. Collected isolates were morphologically and molecularly characterized. Morphological characterization was based on conidia measurements and evaluation of mycelial growth on different artificial media. Tested media included CMA, MEA, OA, PDA, and SNA. Phylogenetic analysis was conducted on a multi-locus approach (ITS + tef1 + tub2) based on Maximum Parsimony and Maximum Likelihood. Results showed that our isolates clustered with S. pistaciarum. Pathogenicity test was conducted in the field using conidia suspensions in order to fulfill Koch's postulates. Presence of characteristic rounded spots and pycnidia was evaluated on the inoculated leaves 9 and 23 days after inoculation. This study represents the first update on S. pistaciarum in Italy since its first identification in 1934.
... Acacia auriculiformis ITS [197] Ophioceras chiangdaoense Dracaena loureiroi LSU [199] Oxydothis cyrtostachicola Cyrtostachys renda ITS, LSU [200] Oxydothis daemonoropsicola Wallichia siamensis ITS, LSU [200] Oxydothis inaequalis Wallichia siamensis ITS, LSU [200] Oxydothis wallichianensis Wallichia siamensis ITS, LSU [200] Pallidocercospora heimii Eucalyptus camaldulensis ITS, LSU, SSU [31] Acacia auriculiformis ITS, LSU, ACT, CAL, RPB2, TEF, TUB [32] Pallidocercospora konae Eucalyptus camaldulensis ITS [31] Eucalyptus camaldulensis ITS, LSU, ACT, TEF [202] Pallidocercospora sp. Ventilago denticulata ITS, LSU, RPB2 [201] Pantospora chromolaenae Chromolaena odorata ITS, LSU, ACT, HIS, RPB2 [205] Paraconiothyrium magnoliae Magnolia liliifera ITS, LSU, SSU, TUB [128] Paraconiothyrium thysanolaenae Thysanolaena maxima ITS, LSU, SSU [53] Paradictyoarthrinium diffractum Tectona grandis ITS, LSU, SSU [35] Dracaena loureiroi ITS, LSU [203] Rhapis sp. ITS, LSU [203] Acacia mangium ITS, LSU, ACT, CAL, RPB2, TEF, TUB [32] Acacia mangium ITS, LSU, ACT, CAL, HIS, RPB2 [32,75] Eucalyptus camaldulensis ITS, LSU, RPB2 [32] Pararamichloridium caricicola Carex sp. ...
Thailand is rich in fungal diversity and new taxa are continuously introduced. In the last decade there has been a vast improvement on the taxonomy, phylogeny and classification of fungi, including in Thailand. Earlier studies were solely based on morphology while modern research uses morphology and molecular phylogeny. There is a huge gap between currently accepted species numbers and previously described species based on morphology. Hence, clarification of previously introduced species using molecular data and providing missing molecular data for those species, is as important as introducing novel taxa. Correct identification of fungi is important in plant pathology and for quarantine purposes. Some introduced fungal species have been discovered to be species complexes based on modern molecular phylogeny. The adoption of "one fungus one name" has necessitated the updating of previous classifications. There are also many taxa yet to be discovered from Thailand. Thus it is important to recollect, sequence, re-describe and resolve the taxonomic ambiguities. It is important to document all fungal taxa as well as provide information on their life modes and to update plant quarantine checklists. In this review we discuss the status of phytopathogenic fungal identification, evolution of the fungal studies through some well-known examples, modern technologies that can be used, and prospects. Most importantly we provide a checklist of plant associated fungi of Thailand, for which there is molecular data available.
... Leaves with typical symptoms of Septoria leaf spot were collected from a commercial pistachio orchard on Aegina Island, Greece in 2016. Identification of the pathogen as S. pistaciarum was based on the description of Crous et al. (2013). To enhance sporulation, infected leaves were placed in damp chambers for 2 d. ...
Septoria leaf spot is an important disease of pistachio trees in Greece. This study aimed to determine effects of temperature and the incubation period on germination of conidia of Septoria pistaciarum, and to evaluate a generic model to forecast pistachio leaf spot under the field conditions of Aegina Island, Greece. The optimum temperature for conidium germination was 23°C, and germination was inhibited at 35 and 4°C. At constant temperature of 23°C, conidia commenced germination after 9 h. The predictive model indexed disease risk close to 100 at 10 May at two locations (Rachi Moschona and Vigla) in 2017, and first leaf spot symptoms were observed on 17 May. Moderate to high disease severity (>25% leaves infected) were observed in unsprayed trees at the end of May. In 2018, the model indexed risk close to 100 on 9 May at Rachi Moschona, and first symptoms were observed on 18 May. Moderate to high disease severity (>25% leaves infected) were observed in unsprayed trees on 25th of May. This study has shown that the forecasting model can be used in Aegina Island, Greece, to predict the severity of Septoria leaf spot of pistachio.
... The PCR amplification of Actin and β-tubulin zone was followed by 1 cycle for 5 minutes at 94 ºC, 35 cycles of each amplification cycle denaturation (94 ºC, 30 seconds), annealing (coupling), (59 °C actin, 55 °C βtubulin, 30 minutes) and elongation (72 ºC, 1 minute). Finally, 1 cycle was given for 10 minutes at 72 ºC (White et al., 1990;Crous et al., 2013). ...
... Also Davidson et al. (2006) stated that the β-tubulin gene is the most conserved genes in fungi and can be used to control DNA quality for PCR reactions. Studies have reported that introns in the βtubulin genes in fungi may provide some evidence for evolutionary relationships between species (Crous et al., 2013). β-tubulin gene has also been used to maintain the quality of fungal gDNA and PCR reaction conditions (Dao et al., 2005). ...
Pistachio (Pistacia vera L.) is a strategic crop plant and Turkey is one of the major pistachio producing county together with Iran, Syria and the United States of America. Pistachio trees are affected by many fungal diseases. The Aspergillus spp. are one of the most important agent that produce mycotoxins and also known as human and animal pathogens. This study was conducted to determine the genomic DNA polymorphisms from Aspergillus spp. which were isolated from pistachio fruits collected from different climatic zones in Turkey. Total of 27 Aspergillus spp. isolates were used and specific primers for ITS, Actin and β-tubulin genes were subjected to RFLP analysis by using Hind III, Pst I, Taq I and Eco RI restriction enzymes. Three different groups were defined with the enzyme Taq I in the β-tubulin region. The results revealed low polymorphism and genetic diversity in Aspergillus spp. with PCR-RFLP of the ITS and actin regions.
(PDF) PCR-RFLP Analyses of Aspergillus spp. Isolated from Pistachio in Turkey. Available from: https://www.researchgate.net/publication/348843928_PCR-RFLP_Analyses_of_Aspergillus_spp_Isolated_from_Pistachio_in_Turkey [accessed Jan 28 2021].
... Crous et al. 2013b( .5 - 1 - ﺗﻔﻜﻴﻚ ﮔﻮﻧﻪ ﻫﺎ ي Pseudocercospora ﺑﺮ اﺳﺎس ﻧﻮاﺣ ﻲ ژﻧ ﻲ ﭘﮋوﻫﺶ ﻫﺎي در ﮔﺮﻓﺘﻪ اﻧﺠﺎم ﻓﻴﻠﻮژﻧﺘﻴﻜﻲ ﮔﻮﻧﻪ ﻣﻮرد ﻫﺎي Pseudocercospora ﻧﻤـﻮده ﻣﺸـﺨﺺ ا ،ﻧـﺪ ﻛﻪ ﻧﺎﺣﻴﻪ اﻳﻨﻜﻪ وﺟﻮد ﺑﺎ ITS-rDNA ﺑﺎرﻛﺪﮔﺬاري ژن ﻋﻨﻮان ﺑﻪ DNA در ﻗﺎرﭼﻬﺎ اﺳـﺖ ﺷـﺪه ﻣﻌﺮﻓـﻲ ) Schoch et al. 2012 ﺟـﻨﺲ در ﻧﺎﺣﻴـﻪ اﻳـﻦ اﻣـﺎ ،( Pseudocercospora از ﺣﻔﺎﻇﺖ ﺷـﺪﮔ ﺑـﺎﻻﻳﻲ ﻲ ﺗﻔﻜﻴﻚ ﺑﺮاي و ﺑﻮده ﺑﺮﺧﻮردار ﮔﻮﻧﻪ ﻫﺎ ﺑـﻪ ﺟـﻨﺲ اﻳﻦ ي ﺗﻨﻬـﺎ ﻧﻴﺴـﺖ ﻛـﺎﻓﻲ ﻳﻲ ) Crous et al. 2013a, Bakhshi et al. 2014, Silva et al. 2016, ) ﻫﻤﻜـﺎران و ﻛـﺮاوس ﺗﺤﻘﻴﻘﺎت .( a 2013 ﻛـﻪ داد ﻧﺸـﺎن ( ﻧﺎﺣﻴﻪ اﻳﻦ ﺗﻨﻬﺎ ﺗﻤﺎﻳﺰ ﺑﻪ ﻗﺎدر 25 از ﮔﻮﻧﻪ 146 ) ﮔﻮﻧﻪ 17 % ) ﻫﻤﻜﺎران و ﺳﻴﻠﻮا ﻫﻤﭽﻨﻴﻦ .ﻣﻴﺒﺎﺷﺪ ( 2016 ( ﺗﻨﻬﺎ 12 از ﮔﻮﻧﻪ 82 ) ﮔﻮﻧﻪ 14 % ﺑـﻴﻦ در .ﻧﻤﻮدﻧـﺪ ...
... The cultivation is generally conducted under dry conditions in Turkey, unlike in Iran and the USA [2]. Hence, Alternaria spp., Aspergillus flavus, Pseudocercospora pistacina, and Septoria sp. are the main disease-causing fungal agents in the pistachio orchards of Turkey [4,5]. P. pistacina and Septoria sp. are foliar phytopathogens, while Alternaria spp. ...
This study examined the ecological properties, 16S rRNA definition and in vitro antagonistic effect of Bacillus spp. against Alternaria spp., Aspergillus flavus, Pseudocercospora pistacina and Septoria sp., which are destructive pathogens of pistachio nut. Bacillus spp. were isolated from rhizosphere soil samples of mined borderlines (Area I), naturally growing pistachio areas (Area II), and pistachio orchards applying standard/conventional agricultural practices (Area III). A total of 106 Bacillus spp. were isolated and 11 taxa were defined through 16S rRNA sequence analyses. Canonical correspondence analysis (CCA) was used to examine the relationship between Bacillus species and environmental variables including macro- and micro-elements, physical and chemical properties of the soil samples. The highest antagonistic activity was exhibited by B. amyloliquefaciens, B. atrophaeus, B. subtilis, B. licheniformis, and B. pumilus strains isolated from area I. Furthermore, antagonistic B. pumilus, B. mycoides, and B. amyloliquefaciens strains showed tolerance to Zn and Mn indicated by CCA. To the best of our knowledge, this is the first report on determination of alternative biological control agents and their possible use in integrated pest management strategies in pistachio orchards.
