Plant Protection

Two powdery mildew species have been collected from Iran. For the first time, Erysiphe magnifica on Magnolia sp. was identified from Iran based on morphological and molecular characteristics. Erysiphe corylacearum was collected for the second time in the country and reported for the first time from Guilan province. There are some polymorphisms in ITS-rDNA sequences of E. corylacearum between Iranian and GenBank sequences. This polymorphism is worth of attention for better understanding of the taxonomy of the species and role of ITS sequences for species delimitation. The ITS sequence of the Iranian specimen of E. magnifica was 100% identical to four ITS sequences of E. magnifica in GenBank. Morphologically, E. magnifica was characterized by curved, flexuous and relatively long foot cells, whereas, foot-cells of conidiophores have been reported in the literature as relatively short. According to these observations, it is recommended to check as many characters as possible for identif...

The Erysiphaceae are obligatory and biotrophic fungal parasites that infect many landscape and ornamental plants which results in reduction of beauty and marketability of these plants. This study was performed to identify powdery mildew fungi on landscape and ornamental plants in four provinces (Isfahan, Chaharmahal & Bakhtiari, Markazi and Lorestan) of Iran. Consequently, 24 powdery mildew taxa on 28 host species were collected during 2017 to 2019. According to our findings,Golovinomyces asperifolii (on Nonea sp.) and Podosphaera euphorbiae-helioscopiae (on Pedilianthus sp.) are new records to Iran mycobiota. Three plant species including Coreopsis sp., Catharanthus roseus and Fragaria vescaare new hosts for powdery mildew fungi of Iran. Moreover, Podosphaera xanthii on Dahlia sp. is reported for the first time from Iran.

Numerous newly collected & herbarium specimens belonging to the genus Cercospora on a variety of host plants were examined using light microscopy. Six species including Cercospora althaeina, C. flagellaris, C. texensis, Passalora circumscissa, Pseudocercospora daturina & Cercospora apii s.l. (C. avicennae, C. brachiata, C. brunkii, C. daturicola, C. hydrangeae, C. rumicis, C. kikuchii, C. xanthiicola & C. zinniae) were identified. Among these species, C. flagellaris, C. texensis, Pseudocercospora daturina are recorded for the first time from Iran. Species of Amaranthus, Datura, Rumex, Xanthium & Zinnia, respectively, are reported as new host for C. brachiata, C. rumicis, C. xanthiicola , C. zinniae in Iran.

This study was carried out to continue identifying unknown and less known anamorphic fungi from Guilan province. Plant materials with fungal signs and symptoms were collected and examined to identify causal agents. Four species viz. Alternaria calendulae (on Calendula officinalis), Pseudocerco-spra sordida (on Campsis sp.), Thedgonia ligustrina (on Ligustrum vulgare) and Zygosporium oscheoides (on decaying leaves of Bilbergia sp., Monstera deliciosa, and stem of Asparagus sp.) are reported as new to Iranian mycobiota.

The newly recognised powdery mildew species Phyllactinia takamatsui on Cotoneaster nummularius (Rosaceae) is described and illustrated. This species, collected in Kerman Province, Iran, is well characterised by its conidial morphology and rDNA ITS sequences clearly different from allied species. Conidia are broadly ellipsoid to subcylindrical, i.e. they are not clavate-spathuliform as in most Phyllactinia species. The rDNA ITS sequence analysis showed that this species is closely allied to other species described on hosts belonging to Rosaceae, such as Ph. mali and Ph. pyri-serotinae. The ITS sequence of P. takamatsui was 92 to 94 % similar to that of the closest known relatives. The new species is described in detail, illustrated and compared with other similar taxa.

Powdery mildew is one of the most important disease concerns of tomato production in different regions of the world, which is caused by different species of Erysiphales. The most important causal agents of which are Leveillula taurica and Oidium neolycopersici. In the present study tomato farms in Qazvin province were surveyed and tomato leaves with powdery mildew symptoms were collected. After morphological studies in laboratory and using reliable resources, the causal agent of tomato powdery mildew was identified as Leveillula taurica. The host range was determined by inoculation of Leveillula taurica from tomato on nine species of plants belonging to four different plant families. All cultivars of tomato, eggplant, pepper and cucumber used in this study, showed disease symptoms on their leaf surfaces. Other plant species including potato, alfalfa, sunflower, clover and sainfoin did not get infected by the pathogen. The nucleotide divergence for the rDNA internal transcribed space...

Sooty molds are a group of fungi with dark-coloured hyphae, which grow saprophytically on various living plant organs and sometimes on non-living substrates and produce brown to black superficial colonies, black pellicles or pseudoparenchymatous crust. In north of Iran including Guilan and Mazandaran provinces, sooty molds are common on living leaves of a great variety of plants especially Citrus spp. There are a few sporadic reports of sooty mold fungi from Iran in the literature. In continuation of an earlier investigation, sooty molds from different citrus species collected from western parts of Mazandaran province and specimens obtained from fungal collection at University of Guilan were studied. As a result, five mitosporic species viz., Chaetasbolisia falcata, Cylindroxyphium virginianum, Fumiglobus citrinus, Fumiglobus foedus and Polychaeton tenellum, and one ascomyceteous species Phaeosaccardinula epicarpa, were identified as causal agents of sooty mold on citrus plants in t...

During 2011, twigs, leaves and fruits of symptomatic hosts containing Fusicladium species from Guilan, Mazandaran, Qazvin and Ardabil provinces were sampled and examined. Five species including F. carpophilum, F. fraxini, F. oleagineum, F. pomi and F. pyrorum were identified based on morphological data. Of these, F. carpophilum and F. fraxini are identified as new records for the mycobiota of Iran. Fraxinus sp., Prunus persica var. nectarina, Pyracantha sp., red apple cultivar of Malus pumila and Khoj (local variety of Pyrus communis in Guilan province) are identified as new hosts for the  genus Fusicladium in Iran. Cultures of F. fraxini, F. pomi and F. pyrorum are deposited at fungal culture collection of Iranian Research Institute of Plant Protection. A brief description and illustration and a key to Fusicladium species reported from Iran are provided.

Recently performed phylogenetic-taxonomic analyses of species belonging to Erysiphe sect. Uncinula on willows (Salix spp.) demonstrated a much higher diversity than previously assumed. Phylogenetic analyses and morphological examinations of Chinese Erysiphe collections on Salix abscondita (= S. raddeana), S. sinica and S. taraikensis, all belonging to Salix subgen. Vetrix sect. Vetrix, revealed an additional cryptic species in sister position to the E. salicis clade, which is described as Erysiphe salicina. The new species clearly distinguished from all allied species in morphological and genetical results. The phylogeny of the new species and closely related species on Populus and Salix spp. (Salicaceae) was reconstructed and discussed using a combined alignment of the internal transcribed spacer (ITS) regions and 28S rDNA sequences. The present phylogenetic analyses suggest that the recently described E. salicicola (on Salix gracilistyla in South Korea) has to be reduced to synony...

During a survey of aquatic fungi from Anzali Lagoon in Iran, several fungal specimens were isolated from freshwater habitats. Morphological evidence and comparing sequencing based on rDNA (ITS and LSU) and protein-coding genes (TEF1 and TUB2) showed that some isolates belong to undescribed fungal species. These isolates belong to Arthrobotrys and Sarocladium, two ascomycetes genera. Arthrobotrys hyrcanus, sp. nov., differs from closely related species such as A. dianchiensis by its larger conidia and septation of primary conidia. Sarocladium pseudokiliense, sp. nov., was similar to S. kiliense, but distinguished by its conidial shape and the absence of adelophialides and chlamydospores. Morphological descriptions, illustrations and multilocus phylogenetic analysis for both new species are provided.

Colletotrichum species are associated with citrus plants as pathogens, saprobes and endophytes. According to the most recent multigene phylogenetic analysis, a lot of changes were happened in the taxonomy and species delimitation in the genus Colletotrichum. In this investigation, 292 Colletotrichum isolates were obtained from leaves, fruits and stems of Citrus species at Golestan, Mazandaran, Guilan and Kerman provinces. After morphological studies, a multilocus molecular phylogenetic analysis (TUB2, CHS–1, CAL) of 13 isolates were carried out. Based on the morphological and molecular data, five species including C. gloeosporioides s. s., C. fructicola and C. siamense (from C. gloeosporioides s. l.); C. karstii and C. novae zelandiae(from C. boninense s. l.) were identified. According to our knowledge, this is the first report of C. novae–zelandiae from Iran and C. siamense and C. karstii from citrus plants in the country.

Summary Sclerotium rolfsii is a soil borne pathogen responsible for root and stem rot on a wide range of crops. This study was conducted to identify the virulence of different S. rolfsii isolates on a susceptible local peanut germplasm and determine the resistance of 20 peanut genotypes to the most virulent isolate and also the relationship between virulence and mycelial compatibility groups (MCGs). Seventy eight isolates of this fungus from 10 host plants and six known MCGs were used in the experiment. The experiment was done in greenhouse conditions (25±5°C) using a complete randomized block design with three replications. Pots containing sterile soil (pH=6.7) were inoculated with barley seeds colonized by each isolate separately before being seeded with the peanut germplasm. Disease severity was assessed by scoring the wilting, yellowing or death of plants, mycelia or sclerotia production on the soil surface or on plant stem, stem area affected (%) and stem lesion length, at the ...

During a survey of xylarialean fungi in Northern Iran, several specimens that showed affinities to the Hypoxylon rubiginosum complex were collected and cultured. A comparison of their morphological characters, combined with a chemotaxonomic study based on high performance liquid chromatography, coupled with diode array detection and mass spectrometry (HPLC-DAD/MS) and a multi-locus phylogeny based on ITS, LSU, rbp2 and tub2 DNA sequences, revealed a new species here described as Hypoxylon guilanense. In addition, Hypoxylon rubiginosumsensu stricto was also encountered. Concurrently, an endophytic isolate of the latter species showed strong antagonistic activities against the Ash Dieback pathogen, Hymenoscyphus fraxineus, in a dual culture assay in our laboratory. Therefore, we decided to test the new Iranian fungi for antagonistic activities against the pathogen, along with several cultures of other Hypoxylon species that are related to H. rubiginosum. Our results suggest that the a...