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AbstractThe bulb onion (Allium cepa) is second only to tomatoes in value of vegetable crops cultivated worldwide. Water-soaked lesions, bleaching and blight on leaves and slippery skin, sour skin, soft rot near the neck and centre rot on onion bulbs were observed in surveys of the onion fields, storage as well as fruit and vegetable markets of northwestern provinces of Iran in 2020. Thirty-four samples were collected from onion fields of East Azerbaijan, West Azerbaijan and Zanjan provinces and the central storage of Bonab city. Fifty bacterial strains were isolated from symptomatic samples. Pathogenicity of the strains was confirmed by inoculating on onion bulb cultivars Azarshahr and Ghermez Anari. Twenty-eight strains were able to induce soft rot on the inoculated sites of cut onion bulbs. Onion bulbs turned dark brown at lesion sites and became odorous over time. All pathogenic strains were Gram-negative, facultative aerobic and catalase positive. Strains mainly varied in starch and aesculin hydrolysis, potato rot and hypersensitive reaction. Pathogenic strains separated into four groups based on phenotypic assays. In the phylogenetic tree based on concatenated sequences of gyrB and infB genes, the strains were divided into four clusters containing the type strains of Enterobacter ludwigii, Klebsiella variicola, Proteus mirabilis and Pantoea agglomerans, confirming their identity as belonging to these four species. This is the first report of P. mirabilis as a plant pathogen and of K. variicola as a causal agent of onion bulb rot. Moreover, this is the first report of E. ludwigii and P. agglomerans associated with onion bulb rot in Iran. [ABSTRACT FROM AUTHOR]

This article reports on the first occurrence of leaf spot disease caused by Penicillium crocicola on Ficus maclellandii plants in Iran. The symptoms of the disease include necrotic spots on the leaves, which gradually turn brown with a yellowish border. The fungal isolates were recovered from the infected tissues and identified based on morphological and molecular characteristics. Pathogenicity tests confirmed that P. crocicola is the causal agent of the leaf spot disease. This is the first report of P. crocicola as a plant pathogen, highlighting its potential as a pathogen for F. maclellandii. [Extracted from the article]

Pythium oligandrum is known as an important biological control agent against fungal plant pathogens. The commercial formulations of this oomycete could reduce the application of the chemical fungicides and lessen the environmental impact of treatments. This study aimed to investigate the antagonistic ability of Iranian isolates of P. oligandrum to select proper and efficient candidates as native biocontrol agents using a previously characterized collection of forty-five isolates from fields of different regions of Iran. The antagonistic effects of native P. oligandrum isolates were evaluated against two soil-borne fungal pathogens, Fusarium oxysporum f. sp. lycopersici and Phytophthora parasitica, causing diseases on tomato. Pythium oligandrum isolates K29, K48, and K87 were recognized as the most effective isolates based also on previously published in vitro antagonistic assays, oligandrin production, and the ability of root colonization. The oospores of the selected candidates were formulated as seed-coating, kaolin dust mixture, and perlite-coating and compared with common fungicides in greenhouse tests. The results of greenhouse studies revealed that all selected P. oligandrum isolates and chemical fungicides significantly reduced disease severity but the efficacy of P. oligandrum isolates varied according to the type of formulation. Seed-coating formulation with oospores exhibited better performance than other formulations. The results showed that the application of formulated P. oligandrum selected isolates had the same performance (40–50% reduction in disease severity) as compared to the chemical fungicide treatments for controlling soil-borne pathogens. These results make it possible to consider in the near future the use of isolates of P. oligandrum as biocontrol agents to protect vegetable crops, in particular tomato, from soil-borne pathogens. [ABSTRACT FROM AUTHOR]

The canker disease caused by Leucostoma cinctum is one of the most destructive diseases in fruit trees in Iran. For investigation of mycelial/sexual compatibility in L. cinctum, 64 isolates from 10 different plants, and 11 provinces of Iran were used. Isolates were crossed in all possible combinations on PDA at 25 °C for mycelial compatibility, and 14 multi-merge MCGs were identified among the isolates, revealing the average genetic diversity. In vitro sexual reproduction of the fungus was assessed using 14 ascospore progeny of two different perithecia, and the isolates were crossed in all possible pairwise combinations on culture media amended by different sterilized twigs. In four crosses on oatmeal agar with 2.5% sucrose, and apricot twigs, fertile perithecia were formed after 5 months, confirming heterothallic nature of the L. cinctum. Also, this is the first report of the in vitro viable sexual reproduction of the L. cinctum in the world. [ABSTRACT FROM AUTHOR]

The family Geminiviridae with fourteen accepted genera and an increasing number of unassigned species is currently identified as the largest family of plant‐infecting viruses. Their twinned icosahedral particles contain single-stranded genomic DNAs that are naturally transmitted by Hemiptera insects including whitefly (Bemisia tabaci), several species of leafhoppers, treehoppers and one species of aphid in a wide range of host plants. Also, some geminiviruses are transmitted by seeds in certain hosts. In addition to climate changes, industrial cultivations, and the development of global trade, the genetic flexibility of geminiviruses has led to an increase in the rate of their distribution. Diseases caused by geminiviruses constitute a serious constraint to tropical and sub-tropical agroecosystems worldwide. The economic losses caused by geminivirus infections have grown especially in open fields and greenhouses in Iran during the last years. Defining two distinct genera by having unique molecular and biological characteristics, Becurtovirus and Turncurtovirus, and the presence of different species and strains of other geminiviruses introduces Iran as a putative origin of diversification for old-world monopartite geminiviruses. This review presents the occurrence and diversity of the members of Geminiviridae in Iran. Moreover, some applicable control measures have been proposed based on compatibility with the Iran agroecosystem which would also be recommended for other tropical and subtropical regions of the world. [ABSTRACT FROM AUTHOR]

Neoscytalidium novaehollandiae is one of the most important pathogens on woody plants which has increasingly been reported as a pathogen in different hosts in recent years. The pine trees are widely cultured in many cities of Iran. In recent years, dieback symptoms were observed on Pinus eldarica trees in Tehran and Qazvin provinces. The aim of this study was to investigate the dieback causal agent on P. eldarica trees in Iran. The branches and cones of P. eldarica trees were sampled for fungal isolation. The morphological and molecular characterizations (ITS, LSU, and TEF1-α regions) identified N. novaehollandiae as a dieback causal agent. This is the first report of N. novaehollandiae disease of P. eldarica trees in Iran. Furthermore, disease severity was assayed on 19 urban forest trees under three different temperature and relative humidity (RHs) regimes. C regime (29 °C and 15% RH) displayed more disease severity on detached branches than B (24 °C and 80% RH) and A (19 °C and 35% RH) ones. This study presents the host range of this pathogen, and showed that these potential hosts are prone to this pathogen under high temperature and low humidity which urban forest trees experienced in recent decades. [ABSTRACT FROM AUTHOR]

Bacillus bacteria are a group of plant growth stimulants that increase plant growth and resistance to plant pathogens by producing various metabolites. With their large surface area and small size, nanoparticles can be used in controlled-release formulations and increase the efficiency of the desired product. Encapsulation of biological agents in combination with nanoparticles can be an essential step in increasing the performance of these agents in adverse environmental conditions. In this study, which is the result of a collaboration between scientists from Italy and Iran, Bacillus velezensis was encapsulated in alginate combined with whey protein and zedo, mastic, and tragacanth gums in the presence of silica and titania nanoparticles to obtain two-layer and multilayer assemblies acting as novel, smart micro-encapsulation systems. The results of laboratory studies showed that the B. velezensis could produce protease, lipase, siderophore, auxin, and a dissolution of mineral phosphate. Scanning electron microscopy images (SEM) showed that the studied microcapsules were almost spherical. Moisture affinity, swelling, and efficiency of each microcapsule were examined. The results showed that the highest encapsulation efficiency (94.3%) was related to the multilayer formulation of alginate-whey protein-zedo. XRD and FTIR spectroscopy showed that the alginate, whey protein, and zedo were mixed properly and no incompatible composition occurred in the reaction. This study aimed to provide a suitable formulation of biofertilizers based on biodegradable compounds as an alternative to chemical fertilizers, which is low cost and very effective without harming humans and the environment. [ABSTRACT FROM AUTHOR]

During 2017–2018, leaf spots were observed on Japanese privet plants in commercial greenhouses and ornamental nurseries in Tehran, Fars and Bushehr provinces, Iran. Due to the high severity of the symptoms, this study was conducted to identify the causal agents. Based on morphological characteristics and molecular analyses of six loci (ITS, act, tef1, gapdh, LSU, and rpb2), the strains isolated were identified as Phyllosticta capitalensis. Pathogenicity was verified with Koch's postulates. To the best of our knowledge, this is the first report of P. capitalensis causing leaf spot on Japanese privet in Iran. [ABSTRACT FROM AUTHOR]

In February 2020, stem cankers and necrotic lesions were observed on Fatsia japonica in the Khuzestan province, Iran. Four identical isolates were obtained from symptomatic tissue and identified as Botryosphaeria dothidea based on morphology and phylogenetic analysis of the ITS and tef1 gene regions. The pathogenicity of the isolates was confirmed by inoculating healthy shrubs of F. japonica. [ABSTRACT FROM AUTHOR]

Phytopythium is a globally distributed genus, species of which occur in various ecological niches. Despite their importance as plant pathogens, information on species diversity and their distribution in West Azarbaijan Province of Iran is limited. This study aimed to investigate the taxonomy and plant pathogenicity of Phytopythium isolates recovered from soils in the province. A polyphasic taxonomy based on morphological, cultural, and multilocus sequence data revealed two new species, described here as P. babaiaharii and P. longitubum. In addition, a putatively new species and five known species, P. boreale, P. carbonicum, P. mercuriale, P. ostracodes, and P. vexans, were found in the studied region. Phytopythium ostracodes, P. mercuriale, and P. boreale were the three most frequent species isolated from soil, although P. mercuriale was only found in one field. Among the studied species, P. mercuriale, P. ostracodes, and P. vexans exhibited various levels of pathogenicity on sugar beet, sunflower, and tomato, and P. boreale was documented for first time as a plant pathogen. Phytopythium ostracodes was highly aggressive on sugar beet and sunflower but lowly aggressive on tomato, whereas P. vexans exhibited high aggressiveness toward the three crop plants. Both P. boreale and P. mercuriale were found to be lowly aggressive on the host plants. The results indicated that members of Phytopythium, particularly plant-pathogenic species, are common in arable soils of West Azarbaijan Province and can pose a threat to agricultural crops in the region. [ABSTRACT FROM AUTHOR]

Background: Root-knot nematodes (Meloidogyne spp.) are among the most important plant pathogens. Biological control is one of the safety and effective methods for control of these nematodes. The aim of the present study was the isolation and identification of endophytic bacteria from tomato fields in some areas of Iran in order to evaluate their biocontrol potential against root-knot nematode. In the present study, the population of Meloidogyne was collected from infected cucumber roots of a greenhouse, and the bacteria were isolated from tomato samples collected from the fields in West-Azarbaijan province of Iran. The effects of the bacterial isolates on hatching and mortality of nematode second-stage juveniles were evaluated, and the effects of six selected isolates on infection of a susceptible cultivar of tomato with nematode were evaluated under greenhouse conditions. Results: The root-knot nematode was identified as Meloidogyne incognita. Results showed that the all isolates exhibited considerable inhibitory effects on nematode hatching. The bacterial isolates also caused the mortality of juveniles. Six bacterial isolates with notable biocontrol potential were selected, and supplementary experiments and molecular identification of selected bacterial isolates were performed. Isolates 1, 2, 5, 7, 10, and 11 were identified as follows: Bacillus wiedmannii (MW405861), Pseudoxantomonas mexicana (MW405860), Pseudomonas thivervalensis (MW405862), Serratia liquefaciens (MW405864), Pseudomonas chlororaphis (MW405863), and P. fluorescens (MW405825), respectively. Based on the results of the greenhouse experiment, the selected isolates exhibited good results in terms of reduction of galls and egg masses of nematode. However, B. wiedmannii and S. liquefaciens had the best results in reduction of all investigated factors compared to other isolates. P. mexicana, P. chlororaphis, and P. fluorescens resulted moderate effects. P. thivervalensis was less effective than the others and in some cases had no effect on nematode reduction. Conclusions: The results showed that endophytic bacteria are good candidates for management of root-knot nematodes. The use of such agents instead of chemicals will be very valuable to the control of nematodes. [ABSTRACT FROM AUTHOR]

Lawson cypress (Chamaecyparis lawsoniana), an important landscape tree, is widely planted in gardens and parks throughout Iran. Crown gall disease on Lawson cypress trees was observed in Sari and Juybar Counties, Mazandaran province, northern Iran, in 2017. Isolation from galls on potato dextrose agar (PDA) containing CaCO3 yielded bacterial colonies, the predominant types of which were purified and selected for characterization. The isolates were Gram‐negative, oxidase positive, able to grow in 2% NaCl and produced 3‐ketolactose. They hydrolysed esculin, casein and arbutin but not starch, gelatin or Tween 80. Two representative isolates were selected for PCR amplification and sequencing of DNA gyrase subunit B (gyrB) gene. In the phylogenetic tree based on the partial sequence of the gyrB gene, isolates KH1 and KH2 clustered with Agrobacterium pusense. The pathogenicity of all isolates was confirmed by inoculation on Jimsonweed (Datura stramonium) and carrot discs (Daucus carota). Confirmation of the presence of genes involved in pathogenicity was made by performing PCR with the virD2A/virD2C and VCF/VCR primer pairs which resulted in amplification of the expected 224 and 730 bp fragments in all studied isolates, respectively. A. pusense was therefore identified as the causal agent of crown and stem gall of Lawson cypress. This appears to be the first report on the natural occurrence of crown gall disease on Lawson cypress and the first record of a plant disease caused by A. pusense. [ABSTRACT FROM AUTHOR]

Introduction: Colletotrichum species are well-known plant pathogens, which have been increasingly reported as the cause of keratitis or subcutaneous lesions in humans. In this study we reported a rare case of fungal keratitis from Iran and reviewed the literature. Case Presentation: A 69-year-old man whose right eye was injured by herbal material was examined by slit-lamp biomicroscopy and mycology investigation of corneal scrapings was done. The grown filamentous fungal was identified as Colletotrichum gloeosporioides based on morphological characteristics and DNA sequence of the internal transcribed spacer region. The isolated strain was sensitive to amphotericin B, caspofungin, anidolafungin, micafungin, voriconazole, and relatively resistant to fluconazole, and itraconazole. Patient was successfully treated with voriconazole. Conclusions: This report highlights that the early and accurate identification and therapy can helpful to management keratitis caused by C. gloeosporioides. [ABSTRACT FROM AUTHOR]

Brenneria species are bacterial plant pathogens mainly affecting woody plants. Association of all members with devastating disorders (e.g., acute oak decline in Iran and United Kingdom) are due to adaptation and propathogenic behavior in response to host and environmental factors. Some species, including 8. goodwinii, 8. salicis. and B. nignfluens, also show endophytic residence. Here we show that all species including novel Brenneria sp. are closely related. Gene-based and genome/pangenome - based phylogeny divide the genus into two distinct lineages, Brenneria clades A and B. The two clades were functionally distinct and were consistent with their common and special potential activities as determined via annotation of' functional domains. Pangenome analysis demonstrated that the core pathogenicity factors were highly conserved, an hrp gene cluster encoding a type III secretion system was found in all species except 8. corticis. An extensive repertoire of candidate vii-ulence factors was identified. Comparative genomics indicated a repertoire of plant cell wall degrading enzymes, metabolites/antibiotics, and numerous propathogenic phages providing new insights into Brenneria-host interactions and appropriate targets for further characterization. This work not only documented the genetic differentiation of Brenneria species but also delineates a more functionally driven understanding of Bre mieria by comparison with relevant Pectobacteriaceae thereby substantially enriching the extent of information available for functional genomic investigations. [ABSTRACT FROM AUTHOR]

Pythium oligandrum is an important potential biological control agent of plant pathogens. The objective of this study was to evaluate the genetic diversity and population structure of 45 isolates from various provinces in Iran. Genetic diversity was characterized based on inter-simple sequence repeat (ISSR) markers. Cluster analysis of ISSR data categorized the isolates into three main clusters. A high level of variability was revealed within P. oligandrum isolates, however, no significant diversity among geographical regions was observed and isolates from different regions were grouped into the same cluster. Genetic diversity was moderate within populations (i.e. Bushehr, Fars and Kermanshah) with high average gene flow and low genetic distances between populations. The observed and effective numbers of alleles were higher in the Fars population than in other studied populations. This is the first report on the genetic diversity of P. oligandrum using ISSR markers. This study paves the way for the selection of isolates to be assessed for their antagonistic efficacy. [ABSTRACT FROM AUTHOR]

Trichoderma fungus species are highly populations of fungi in world that they can colonize roots as plant symbiosis. Various types of Trichoderma are free-living fungi that are, generally, saprophytic on the remains of soil. In addition to its role in biological control, this fungus increases plant yield and growth. So far, many studies have been conducted to examine the ability of this agent to reduce biological tensions and biological control of plant pathogens. Thus, this study was conducted to isolate and identify species of Trichoderma fungus from rapeseed fields in Golestan and Qazvin province from Iran, and also to study isolated species on germination percentage and growth parameters of rapeseed seedlings in a randomized complete block design with three replications in vitro. Based on the results, three species of T. harzianum, T. virens, and T. atroviride were identified, which the isolate of T. harzianum Ta19 showed a significant effect on the control group and other treatments in increasing germination percentage, root length and stem; whereas, the seeds treated with the isolate T. atroviride Ta11 showed no significant difference with the control group in spite of the increase in seed germination rate in comparison with the control and other treatments. According to the results, the use of Trichoderma fungus as a seed treatment like other researches on different products is recommended for increasing the growth of rapeseed. [ABSTRACT FROM AUTHOR]

Net blotch caused by Pyrenophora teres is an important pathogen of barley plants worldwide. There are two biotypes of the fungus. Pyrenophora teres f. teres (Ptt) causes the net form of the disease and Pyrenophora teres f. maculata (Ptm) causes the spot form of the disease. Barley landraces are good sources of disease resistance. In this study, seedling response of 25 barley landraces obtained from different regions of northwest Iran to 3 single spore isolates of Ptt and 3 single spore isolates of Ptm were determined under greenhouse conditions. Differences in virulence among the isolates were evident. Some landraces showed different responses to different isolates. Landraces # 9 and # 16 showed moderately resistant reactions to one isolate of Ptt and showed moderately resistant-moderately susceptible reactions to 2 isolates of Ptt. Landraces # 7, # 11, # 15, # 17, # 21, # 22, # 23 and # 25 showed moderately resistant-moderately susceptible reactions to all 3 isolates of Ptt. Landrace # 23 showed resistant-moderately resistant reaction to one isolate of Ptm and showed moderately resistant reactions to 2 isolates of Ptm. Landrace # 16 showed moderately resistant reactions to all isolates of Ptm. Landraces # 11, # 15, # 21 and # 25 showed moderately resistant reaction to one isolate of Ptm and showed moderately resistant-moderately susceptible reactions to 2 isolates of Ptm. Landraces that exhibited reactions between resistant and moderately resistant-moderately susceptible range could be used as a direct seeding material to the field or could be used as breeding materials. [ABSTRACT FROM AUTHOR]

Phytolasmas are important phloem-restricted plant pathogens which are classified into prokaryotes kingdom and mollicutes class and annually cause considerable loss to crops, ornamentals and trees (Bertaccini et al. 2014). During 2017-18, cowpea fields of Bavi county in Khuzestan province were inspected and cowpea phyllody disease was observed. The clear symptoms of the disease included phyllody, leaf size reduction and stem fasciation (Fig. 1-A). Total DNA was extracted from 34 symptomatic plant samples and 12 healthy plants. In order to detect phytoplasma in DNA samples, direct PCR using P1/P7 primer pair (Deng & Hiruki 1991) and nested PCR using R16F2n/R16FR2 primer pair (Gundersen & Lee 1996) were used and expected fragments of 1830 and 1240 bp were amplified, respectively (Fig. 1-B). The large fragment belonging to the sample collected from Bavi county was isolated, purified and sequenced. Nucleotide analysis of the obtained sequence in NCBI using BLAST software showed the highest (99%) identity to the phytoplasma associated with cowpea phyllody in West Azarbaijan province (KC633094), Vinca virescence (AY500817), Columbia Basin potato purple top (AY692279) and Candidatus Phytoplasma trifolii (KX773529). Additionally, 99% identity to 14 phytoplasmas reported from Iran such as Cucurbita pepo (KP119494), cucumber phyllody (JF508516) and tomato big bud (JF508512) was observed. The nearly complete sequence of 16SrRNA of cowpea phyllody phytoplasma was deposited in GenBank under the accession number of MK088178. This is the first report on the association of a phytoplasma with cowpea phyllody disease in Khuzestan province. Recently, a phytoplasma has been detected among cowpea plants with symptoms including phyllody, leaf size reduction and stem fasciation in West Azarbaijan province which showed highest similarity to clover proliferation group (16SrVI) (Gharouni Kardani & Jamshidi 2018). It seems that the presence of phytoplasma in this province is a real threat to cultivated crops. Symptoms of phyllody, leaf size reduction and stem fasciation were also found in cowpea fields of Ahvaz and Dezful counties and identification of the phytoplasma associated with these symptoms is under investigation. [ABSTRACT FROM AUTHOR]

• The endophytic Bacillus subtilis CB2 was isolated from wheat seeds in Iran. • The enzymes produced by the Bacillus subtilis CB2 and effects of this bacterium on plant growth were evaluated. • This strain partially protected wheat against BLS and FCR. • The isolate increased plant growth and yields. • Surfactins and iturins are responsible for antibacterial and antifungal activity. Fusarium graminearum and Xanthomonas translucens are the causal agents of important diseases in wheat plants worldwide. Seeds carry beneficial microbes known as endophytes that could increase plant growth and have biocontrol activity against pathogens. Therefore, using endophytes could be useful for plant production and they are good alternatives for hazardous synthetic fertilizers or pesticides. In this study, 10 endophytic bacteria were isolated from eight cultivars of wheat surface-sterilized seeds. One isolate based on the result of dual culture assay and its biocontrol activity against mentioned plant pathogens was selected for further evaluation. The isolate was identified as Bacillus subtilis CB2 according to the 16S rRNA and gyrB gene sequencing. Microscopic analysis showed alterations in the fungal hyphal structures. The B. subtilis CB2 could produce protease, amylase, pectinase, cellulase, IAA, ammonia, catalase, and ACC deaminase and could solubilize phosphate. Nevertheless, lipase and chitinase were not produced by the isolate. Spore germination and DON production were reduced when the fungus grew on wheat seeds treated with the B. subtilis CB2. Reduction in percentages of Fusarium head blight infection, Fusarium crown rot severity, and protection rate against bacterial leaf streak were 80.33%, 78.19%, and 64.23%, respectively. Greenhouse trials revealed that the biomass and 1000-grain weight of the treated plants with the Bacillus subtilis CB2 were increased. The crude lipopeptide extract of the isolate inhibited growth of both plant pathogens. LC-MS analyzes showed that the B. subtilis CB2 could produce surfactins and iturins, which are known as antibacterial and antifungal lipopeptides. This is the first report that revealed activity of the seed endophytic B. subtilis in biocontrol of the X. translucens and F. graminearum (crown rot). Formulation of this beneficial bacterium and its application in the field conditions could be an environmentally safe strategy for management of plant diseases. [ABSTRACT FROM AUTHOR]

Root-knot nematodes (RKN), Meloidogyne spp. with the dominant species, Meloidogyne javanicaare is considered as the important plant pathogens of agricultural products globally. In this study, chemical management was carried out RKN, M. javanica to investigate the efficacy of Iranian Abamectin insecticide product [acaricideabamectin (Vermectin® 1.8% EC, Gyah Corp., Iran)] verses normal Abamectin available in the market each at the rate of 8 L.ha, on cucumber "Viola" and the controls (infested to RKN and without any chemical pesticides treatments) at the two highly infested-RKN farmer greenhouses in Isfahan, Iran. The results indicated a highly significant reduction in RKN population and increase in biomass parameters at 1% level of significance, respectively. Parameters of RKN in the soil and plant root revealed that the number of nematode larvae, second instar larvae (J2) in the soil was reduced by 95% by the normal Abamectin and 93% by the Iranian Abamectin product in comparison to the initial population, respectively. The number of J2 and eggs in the root was also reduced by 89% in the normal Abamectin followed by 91% in the Iranian Abamectin; gall-index reduction was 56% and 58%; and egg-mass index with 79% and 74% reduction in the roots; and the lowest percentage of reproduction rate was 5.4% and 8.3% in the respective treatments accordingly. The same trend was almost followed for the growth factors parameters (biomass), BGPs. The highest stem fresh and dry weight was recorded in the normal Abamectin followed by Iranian Abamectin. The longest stem and root length and root fresh and dry weight was recorded in the Iranian Abamectin followed by normal Abamectin. In total, the results showed that Iranian Abamectin insecticide is competitive as a nematicide for the management of cucumber RKN compared to normal Abamectin, and is a suitable alternative in RKN management, and could be extended to other agricultural crops accordingly. [ABSTRACT FROM AUTHOR]

During 2012–2014 surveys for the presence of phytoplasma diseases in Fars province (Iran), pomegranate little leaf symptoms were observed in several orchards in Khafr and Neyriz areas. Samples collected from symptomatic plants positively reacted in nested PCR assays using P1/P7 followed by R16F2n/R16R2 primer pairs producing the expected 1,250 bp DNA fragments. Real and virtual RFLP analysis showed that the sequences of phytoplasma strains from Khafr and Neyriz (KPLL and NPLL strains, respectively) were identical to each other and belong to 16SrII phytoplasma group, subgroup D. Phylogenetic analysis of the R16F2n⁄R16R2 DNA region confirmed that KPLL and NPLL phytoplasmas were enclosed in the same clade as other 16SrII-D subgroup phytoplasmas. This is the first reported occurrence of a 16SrII phytoplasma infecting pomegranate trees. [ABSTRACT FROM AUTHOR]

The genus Colletotrichum comprises a number of plant pathogens of major importance which cause anthracnose diseases on a wide range of woody and herbaceous plants worldwide. With the advent of molecular studies, it has been shown that most of the previously known species e.g. C. boninense, C. acutatum, and C. gloeosporioides have been split into several species. In the present study, the identity of Colletotrichum isolates from the northern and northwestern zone of Iran were determined based on multi-gene phylogenetic analyses. Phylogenetic analysis based on a combination of internal transcribed spacer (ITS), beta tubulin (TUB), histone H3 (HIS), calmodulin (CAL), and actin (ACT) loci, clustered our isolates into three clades, including C. salicis on Salix sp., Colletotrichum sp. (C. fuscum sensu lato) within the C. destructivum species complex on Viola sp., and C. fructicola on Citrus sinensis, Malus domestica, Gleditsia caspica, and Sambucus ebulus. These three species are new for mycobiota of Iran. According to these results, Viola sp. from West Azerbaijan (Khoy-Firouragh) is a new host for Colletotrichum sp. in the C. destructivum species complex. Furthermore, C. sinensis from Mazandaran (Behshahr), and G. caspica, and S. ebulus from Guilan (Talesh), are new host records for C. fructicola. [ABSTRACT FROM AUTHOR]

In 2011 and 2012, several cucurbit-growing regions of Iran were surveyed and samples with symptoms similar to those induced by Cucurbit chlorotic yellows virus ( CCYV) were collected. The pathogen was transmitted to cucumber and melon under greenhouse conditions by whiteflies ( Bemisia tabaci). RT- PCR using designed CCYV-specific primer pair ( CCYV-F/ CCYV-R) resulted in amplification of the predicted size DNA fragment (870 bp) for the coat protein ( CP) gene in samples collected from Boushehr, Eyvanakay and Varamin. Nucleotide sequences of the CP of the three Iranian CCYV isolates were compared with five CCYV isolates obtained from GenBank and analysed. Phylogenetically, all CCYV isolates clustered in two groups; Group I is composed of five non-Iranian isolates from China, Lebanon, Japan, Sudan and Taiwan, and the three Iranian isolates formed Group 2. Among Iranian isolates, the Eyvanakay isolate clustered in a distinct clade with the Boushehr and Varamin isolates. A phylogenetic tree based on amino acid identity of CP showed that CCYV was closely related to Lettuce chlorosis virus ( LCV), Bean yellow disorder virus (Bn YDV) and Cucurbit yellow stunting disorder virus ( CYSDV). This is the first report of CCYV in Iran. [ABSTRACT FROM AUTHOR]

Trunk diseases are a potential threat for the almond industry in Northern Iran. In a survey on fungal agents associated with almond die back and decline in East Azerbaijan province, located in Northwest of Iran, acremonium-like hyphomycete isolates with hyaline and simple conidiophores and hyaline cylindrical phialides with a finely pigmented apical region and deep, flaring collarettes were repeatedly recovered from symptomatic tissues. Fungal isolates were identified asCalosphaeria pulchellabased on cultural and morphological characteristics. The identity of the species was further confirmed based on the sequence data from LSU and ITS rDNA regions. A phylogeny inferred using ITS sequence data, clustered theCalosphaeriaisolates together withCalosphaeria pulchellaisolates in GenBank known fromPrunus persicaandPrunus avium. The results of pathogenicity assay using an excised shoot method showed thatCalosphaeria pulchellais highly pathogenic on almond. The distribution and host range of this new pathogen on almond and the impact of the disease on almond industry in this region remain to be studied. [ABSTRACT FROM AUTHOR]

Alfalfa witches' broom (AWB) is a serious disease of alfalfa in Bushehr province. For characterization of Bushehr AWB phytoplasma, alfalfa plants with typical symptoms of AWB were selected in different regions of Busher province including Bondarooz (1 isolate), Sarkoreh (2 isolates), Poshtpar (1 isolate) and Tange- Eram (1 isolate), transferred to greenhouse and used as the source of the disease agent for transmission and molecular studies. Agent of AWB was transmitted from each isolate to periwinkle via dodder inoculation. Agents of all isolates caused little leaf, internode shortening, yellowing, virescence, phyllody and witches' broom symptoms in periwinkle plants. DNA fragments of approximately 1800 bp of ribosomal operon were amplified with primer pair PI/P7 by direct PCR from total DNA samples extracted from naturally alfalfa infected plants and periwinkle plants inoculated with agents of AWB isolates. P1/P7 primedPCR products (1800 bp) were analyzed by digestion with AluI, HpaII, Cfol, HaeIII and RsaI enzymes. RFLP patterns analyzed with these enzymes were similar to each other and those of AWB phytoplama from Fars (Mobarak Abad and Juyom I) and yazd, 16SrII group Related phytoplasmas but distinguishable from a Fars isolate of AWB(Juyom2) by a CfoI site. Phylogenetic analyses of full length 16S rRNA gene sequence also clustered agent of Bondarooz AWB phytoplasma with phytoplasmas of 16SrII group. Based on the results of the present study, a phytoplasma relatede to peanut witches' broom (16srII) is associated with AWB disease in Bushehr province. This is the first report of AWB in Bushehr province [ABSTRACT FROM AUTHOR]

The oil rose, Rosa damascena Mill. (Rosaceae) is an agricultural crop cultivated in various countries of the northern hemisphere, such as Turkey, Bulgaria, Morocco, Iran, Egypt, France, China and India. Iran, presently, is the largest producer of rose water in world. The major production areas in Iran are Kashan, Fars, Kerman and Azerbaijan. Kerman province with 2297 hectares ha of rose gardens and 6198 tons of flower production is one of the important rose production regions. The productions of this region are organic and do not use anychemical compounds such as pesticides and fertilisers. The major fungal pathogens were studied during 2008–2010 in oil rose production areas in Kerman province, Iran. Verticillium dahlias, Rosellinia necatrix, Alternaria alternata, Seimatosporium fusisporum and Podosphaera pannosa have been detected in the oil rose from different regions in Kerman province. A. alternata has the most isolates and infected plants per cent in the oil rose. This is the first report fromVerticillium dahliae, R. necatrix, A. alternata, S. fusisporum on oil roses (R.damascena) in the world. [ABSTRACT FROM PUBLISHER]

Sugar beet roots and the attached soil are transferred to Bardsir factory for processing, and the roots are washed by water pressure. Muddy water flows as waste into canals and are used for irrigation of sugar beet farms. The possibility of occurrence and fluctuations of the pathogenic organisms in irrigation was studied during 2006 and 2007. The samples were collected from the wastewater once a week. Isolation of pathogens was done by four methods: (a) Citrus leaf baiting method and on PARPH selective medium, and common culture media such as: PDA, CMA, MA, NA and WA; (b) Irrigation of sugar beet seedling with wastewater; (c) Bioassay with healthy sugarbeet roots; (d) Cysts of nematode were extracted from waste by sieves. Many different pathogens were isolated from wastewater such as: Fusarium oxysporum, Fusarium solani, Rhizopus stolonifer, Penicillium digitatum, Aspergillus niger, Pythium aphanidermatum, Pythium akanoganese, Phytophthora cryptogea, Phytophthora drechsleri, Mucor sp., Rhizoctonia solani, Geotrichum sp., Erwinia carotovora and cysts of Heterodera schachtii. Pathogencity tests were done for each pathogen. During the first period of processing, the recovery of pythiaceae and Erwinia carotovora was in high level, and in the last period of processing the recovery of Penicillium digitatum, Aspergillus niger, Mucor sp. and Geotrichum sp. showed high levels. The recovery of Alternaria alternata, Rhizoctonia solani and Fusarium solani were stable but the cysts of H. schachtii were variable during the processing period. These pathogens were isolated from sugar beet farms irrigated with wastewater. [ABSTRACT FROM AUTHOR]

There are two major soilborne pathogens that cause diseases in pistachio and olive orchards in Iran. These pathogens are Phytophthora spp. and Verticillium dahliae, which cause gummosis and wilting of trees and seedlings resulting in yield reduction. The population densities of Verticillium dahliae are high in new orchards that have been previously cropped to susceptible cultivars. Propagules of V. dahliae and Phytophthora spp. (P. pistaciae and P. dreschleri) were found at 900 to 1,600 CFU g-1/soil in newly established orchards. Soil solarization was carried out in the studied areas to control these pathogens. After six weeks of solarization, the population density of V. dahliae was reduced from 1,600 CFU g-1/soil to 300 in the orchard soils. This method decreased the incidence of disease up to 70% in the orchards. [ABSTRACT FROM AUTHOR]

Efficacy of commercial detergent and disinfectants to eliminate microorganisms associated with fresh vegetables eaten raw in Iran, including radish, parsley, basil, coriander (cilantro), Allium porrum (leek), and peppermint were studied. The raw vegetables were subjected to a triple wash treatment of washing in tap water for mud removal, washing in water containing a detergent (dishwashing liquid) or disinfectant individually, and rinsing in tap water. The population of total mesophilic microbes on the surface of untreated vegetables ranged from 105 to 106 CFU/g. Washing in tap water or treatment with detergent (333 ppm for 10 min) or benzalkonium chloride (92 ppm for 15 min) reduced the total microbial count, most probable number (MPN) of coliforms, MPN of fecal coliforms, and MPN of fecal streptococci by about 1.2 to 2.3 log. No significant differences in microbial populations were found on vegetables after decontamination with tap water, detergent, or benzalkonium chloride (P > 0.05). Treatments with peracetic acid (100 ppm for 15 min) and hydrogen peroxide (133 ppm for 30 min) reduced the total mesophilic microbial counts by about 2.8 log. The microbial reductions with calcium hypochlorite (300 ppm for 15 min) and combined hydrogen peroxide and silver ion (133 ppm for 30 min) were significantly higher than those obtained after rinsing in tap water or after detergent or benzalkonium chloride wash (P < 0.05). Pretreatment with detergent slightly enhanced the efficacy of all decontamination treatments, but results were not significantly different from those obtained after individual application of disinfectants. [ABSTRACT FROM AUTHOR]

Mosaic disease of eggplant (Solanum melongena L.) is common in many fields of southern Iran. A virus isolated from diseased plants in the Boushehr Province was characterised by biological, serological, physiochemical and molecular studies. The virus was mechanically transmissible to Nicotiana tabacum cv. Turkish and several other solanaceous species and to Chenopodium amaranticolor and C. quinoa. Purified preparations of the virus contained flexuous rod-shaped particles. Two aphid species, Myzus persicae and Aphis gossypii, transmitted the virus between Turkish tobacco plants. An antiserum raised against purified virus preparation was used in the detection of the virus. Molecular weights of the virus genome and the coat protein (CP) were estimated at 3.1?3.2נ106 and 36נ103Da, respectively. The 3? region of the virus genome, including the CP and the untranslated region (UTR), was amplified using two pairs of general primers of the family Potyviridae. Sequence information identified the virus as a strain of Potato virus Y (PVY), designated eggplant strain of PVY (PVY-Eg), with the highest sequence homology to a tomato strain of PVY (PVY-LY84.2) from Spain, and a somewhat lower homology to an Indian isolate of Eggplant mottle virus belonging to the PVYO subgroup. Cluster dendrograms based on CP amino acid and 3?-UTR sequences placed PVY-Eg within the PVYNP subgroup. This is the first report on the characterisation of a PVYNP strain infecting eggplant in Iran. [ABSTRACT FROM AUTHOR]

Phytoplasmas associated with lettuce phyllody (LP) and wild lettuce phyllody (WLP) in southern Iran were partially characterized by molecular analyses and host-range studies. Agents of both diseases were transmitted by Neoaliturus fenestratus, a leafhopper colonizing lettuce and wild lettuce, to lettuce, wild lettuce, sowthistle and periwinkle, but not to safflower, sunflower, calendula and sesame. Both phytoplasmas induced bud proliferation, virescence, phyllody and witches’ broom in infected plants. Total DNA extracted from infected lettuce and wild lettuce or from vector tissues was subjected to PCR using phytoplasma-specific primer pair P1/P7 or nested PCR using P1/P7 followed by R16F2n/R16R2. PCR product of nested PCR (1·2 kbp) was subjected to restriction fragment length polymorphism (RFLP). RFLP analysis of nested PCR product identified the LP, WLP and N. fenestratus-associated phytoplasmas as members of the pigeon pea witches’ broom group, 16SrIX. Phylogenetic analysis of the 16S rRNA gene sequence also clustered LP and WLP phytoplasmas with other known members of the 16SrIX group. While no significant differences could be detected between LP and WLP phytoplasmas, both isolates differed from Lebanese wild lettuce phyllody in molecular properties. [ABSTRACT FROM AUTHOR]

Damage to agricultural crops by tospoviruses has occurred sporadically in Iran in the past; how- ever, since 2000, outbreaks of tospoviruses have been recorded every year. The most affected ornamental crops were surveyed in two main cultivation areas in provinces of Markazi (Mahal- lat) and Tehran in 2000-01 and 2001-02. A few weed species also were collected. In all, 513 samples (with or without any conspicuous virus symptoms) were collected and analyzed by double- and triple-antibody sandwich enzyme-linked immunosorbent assay (ELISA) with poly- clonal antibodies to Tomato spotted wilt virus (TSWV), impatiens necrotic spot virus (INSV), and Tomato Varainin virus (ToVV), a new Tospovirus sp. from Iran. These viruses frequently were detected in samples of many different ornamentals and often in mixed infections, whereas Iris yellow spot virus (IYSV) was detected in only four samples. ToVV also was found in weeds growing in Chrysanthemum fields and in a Cuscuta sp. Applying double-antibody sandwich ELISA, no positive reactions were found with Tomato chiorotic spot virus (TCSV). Of the total of 513 samples tested, 345 samples did not react with any Tospovirus antisera. In Tehran, INSV was identified in 21 samples (10%), IYSV in 4 samples (2%), TSWV in 16 samples (8%), and ToVV in 22 samples (11%). In Markazi province, INSV was identified in 24 samples (8%), IYSV in I sample (0.5%), TSWV in 40 samples (13%), and ToVV in 36 samples (12%). ToVV was found to prevail in Tehran province and TSWV in Markazi. Thrips spp. present at the plant sampling sites also were collected and identified. [ABSTRACT FROM AUTHOR]

Physicochemical, biological, and cytopathological properties of johnsongrass chlorotic stripe mosaic virus (JCSMV) found in Iran were investigated. Virus particles were polyhedral, showed a knobbed surface structure, were c. 30 nm in diameter and had a buoyant density of 1.359 g/ml in cesium chloride. Virions contained one major protein with a molecular weight of 41 kd and a single species of ssRNA with a molecular weight of 1.43 X 106 d. Acid hydrolysis of the virus followed by thin-layer electrophoresis gave the following molar percentages of the bases: A: 23.5, G: 27.5, C: 26 and U: 23. Separation of nucleotides of the viral RNA using alkaline hydrolysis was not successful. Mechanical inoculation of freshly purified virus or isolated RNA failed to infect johnsongrass or maize plants. The virus was readily detected by ELISA in seeds from infected plants and young seedlings raised from such seeds, but not in later stages of growth. Ultrathin sections of infected cells showed high concentrations of virus particles in the cytoplasm and vacuoles. Virus-like particles also occurred in the stroma of chloroplasts and mitochondria. Cisternae of endoplasmic reticulum (ER) were often extremely inflated and filled by a fine fibrillar material. Small membrane-associated vesicles were frequently found in ER elements and occurred also in the perinuclear space. Based on particle structure, properties of the nucleic acid, molecular weight of the coat protein and cytopathology, the virus resembles carmoviruses. However, lack of mechanical transmissibility is not known for any virus classified with this group. No serological reaction was detected with a total of 30 antisera to carmoviruses and other isometric viruses. [ABSTRACT FROM AUTHOR]

Polystigma ochraceum is a major leaf pathogen of almond in Fars Province of Iran. Over a 4-year study period it was found that ascospore discharge began at flowering and continued for 4–5 weeks. The maximum discharge occurred at petal fall. The incubation period was estimated to be 4–5 weeks under experimental conditions. Although the mature ascospores could produce short germ tubes in distilled water or water agar, the fungus could not be cultured or grown on conventional media from either ascospores, pycnidiospores or stromatic tissues under laboratory conditions. Of several systemic and non-systemic fungicides evaluated under field conditions, triforine at 100–400 μg/ml was most effective. Other fungicides which significantly reduced leaf infection were, in order of efficacy, copper oxychloride(2000 μg/ml), copper hydroxide (2000 μg/ml), Bordeaux mixture (10000 μg/ml) and mancozeb(2000 μg/ml). Carbendazim and thiophanate methyl (500 μg/ml) increased the level of infection. One application of the fungicide at petal fall and then two at 14-day intervals were found to be effective in reducing the disease. [ABSTRACT FROM AUTHOR]

Symptoms of pear decline (PD) were observed in several pear growing regions of Iran. Pear trees with typical symptoms of PD from Estahban (Fars Province) were examined for phytoplasma infection using polymerase chain reaction (PCR) assay. Graft inoculation of healthy pear trees with scions from diseased trees resulted in production of PD symptoms and transmission of phytoplasma as verified by PCR. Target DNA was amplified from symptomatic pear trees with fO1/rO1, an apple proliferation (AP) group-specific primer pair. Physical and putative restriction fragment length polymorphism (RFLP) analyses of fO1/rO1 primed PCR products showed profiles corresponding to AP group, 16SrX-C subgroup ( Candidatus Phytoplasma pyri). Percent similarity values and phylogenetic analysis of fO1/rO1 primed sequences confirmed that, as a member of AP subclade, Estahban PD phytoplasma has a closer relationship to PD and peach yellow leaf roll phytoplasmas than to AP ( Ca. Phytoplasma mali) and European stone fruit yellows ( Ca. Phytoplasma prunorum) phytoplasmas. This is the first report of PD phytoplasma in the eastern Mediterranean. [ABSTRACT FROM AUTHOR]

Knowledge of the genetic diversity detected among fungal species belonging to the genus Aspergillus is of key importance for explaining their important ecological role in the environment and agriculture. The current study aimed to identify Aspergillus species occurring in the rhizosphere of sugarcane in the South of Iran, and to investigate their mycotoxin profiles. One-hundred and twenty-five Aspergillus strains were isolated from the soil of eight major sugarcane-producing sites, and were molecularly identified using sequences of partial β-tubulin (benA) and partial calmodulin (CaM) genes. Our molecular and phylogenetic results showed that around 70% of strains belonged to the Aspergillus section Nigri, and around 25% of species belonged to the Aspergillus section Terrei. Species belonging to both sections are able to produce different mycotoxins. The production of mycotoxins was measured for each species, according to their known mycotoxin profile: patulin (PAT) and sterigmatocystin (STG) for Aspergillus terreus; ochratoxin A (OTA) and fumonisins for Aspergilluswelwitschiae; and OTA alone for Aspergillus tubingensis. The data showed that the production of OTA was detected in only 4 out of 10 strains of A. welwitschiae, while none of the A. tubingensis strains analyzed produced the mycotoxin. Fumonisins were produced by 8 out of 10 strains of A. welwitschiae. Finally, none of the 23 strains of A. terreus produced STG, while 13 of them produced PAT. The occurrence of such mycotoxigenic plant pathogens among the fungal community occurring in soil of sugarcane fields may represent a significant source of inoculum for the possible colonization of sugarcane plants, since the early stages of plant growth, due to the mycotoxin production capability, could have worrisome implications in terms of both the safety and loss of products at harvest. [ABSTRACT FROM AUTHOR]

In December 2003, a severe general yellowing and death of the fronds of date palm ( Phoenix dactylifera) occurred in a grove in the vicinity of Kazeron district, west of Fars province, Iran. Fusarium solani was isolated from the crown, and xylem rays sampled from the trunk 1.5 m above soil level. In pathogenicity tests using artificially infested soil and 1-year-old date palm seedlings, an isolate from the trunk (FST) induced general chlorosis and death of seedlings 25–28 days after inoculation. Similar results were obtained when seedlings were planted in naturally infested soil. In both procedures, distal portions of the roots and crown were affected. The fungus was re-isolated from the crown and leaf bases of the inoculated seedlings. This is the first report of a serious disease of date palm, which we call yellow death, incited by F. solani in Iran. [ABSTRACT FROM AUTHOR]

During spring and summer of 2016, dieback symptoms including blights of leaves, twigs, and acorns were observed on current year shoots of Quercus infectoria in the Zagros oak forests of Iran. The fungus isolated from damaged tissues was identified as Discula quercina based on both morphological characteristics and ITS sequencing. To fulfil the Koch's postulates, a representative isolate was inoculated onto shoots of Q. infectoria and Quercus libani in both laboratory and forest conditions. Responses of the two oak species to inoculation with D. quercina were examined under laboratory and forest conditions in a completely randomized experiment. Discula quercina was clearly involved in oak dieback, and Q. infectoria was more susceptible than Q. libani to damage by the pathogen. This is the first record of the occurrence and pathogenicity of the fungus Discula quercina on Quercus infectoria. The fungus is considered as an emerging pathogen on oak trees in Zagros forests in Iran. Furthermore, the pathogenicity of the Discula quercina on Q. libani under laboratory and forest conditions increases the potential importance of this pathogen in Zagros forests. [ABSTRACT FROM AUTHOR]

The article presents a study on microsphaeropsis olivacea fungus causing brown spine rot on Alhagi maurorum weed in Iran. Topics discussed include characteristics of the plant disease, description of colonies of single-spore isolates, and finding on microscopic examination. The confirmation of pathogenicity of the isolates is also discussed.

A chart is presented that shows data on new hosts and distribution areas of plant pathogens in Iran.

The article presents the first report of a phytoplasma associated with Periploca aphylla (P. aphylla) witches' broom in Iran. Symptoms of witches' broom, proliferation and shoot dieback were observed on P. aphylla in Hormozgan province, Iran in September 2008. The affected plants developed dense clusters of highly proliferating branches with shortened internodes. The partial 16SrDNA sequence of the phytoplasma showed a 96% sequence identity with strains of group 16SrX.

The article reports on the association of Candidatus Phytoplasma trifolii-related strain to the safflower phyllody disease in Iran. It mentions that safflower plants with phyllody symptoms were observed in production fields in Iran on 2003. Among the symptoms include floral virescence, phyllody, proliferation of axillary buds, and leaf symptoms. Using nested polymerase chain reaction (PCR) assays, the association of phytoplasma to the disease was verified. The associated phytoplasma was classified as a strain of the aster yellow subgroup 16Srl-B. It is noted that this is the first report of safflower as a host of a Candidatus Phytoplasma trifolii-related strain.

The article discusses a report of a Tospovirus species infecting tomato in Iran. Tomato fruits manifesting a yellow ring patterns were observed during surveys for Tomato spotted wilt virus. A tospovirus was isolated by mechanical transmission to herbaceous hosts. The virus has been classified as a species of the genus Tospovirus for which the name Tomato fruit yellow ring virus is proposed. The virus has an extensive host range, but is found frequently in tomato and in mixed virus infections with Tomato spotted wilt virus.

The article discusses the first report of root and stem rot disease of wheat caused by Bipolaris sacchari in Hamada, Iran. Wheat plants in several fields in Hamada manifested symptoms of root rot and crown necrosis during May and June 2003. The most common fungus isolate was the Bipolaris species. The pathogen discovered was Bipolaris sacchari based on the host origin, conidia and conidiphore morphology, number of pseudosepta and hilium characteristics. Additional field research is required on the ecology and pathogenicity of B. sacchari to develop steps for controlling root and stem rot of wheat.