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Root-knot nematodes (RKNs) are the most destructive nematode species in main pistachio cultivation areas of Iran, and adversely affect crop quality and yield. So far, Meloidogyne incognita and M. javanica have been reported infecting pistachio. In this study, four populations of M. arenaria were found infecting pistachio in Kerman and Khorasan Razavi provinces. The morphology and morphometrics of the recovered populations closely match the data given for other populations of the species. Molecular characterization of the recovered populations was performed by sequencing three genomic and mitochondrial regions, including D2-D3 of LSU rDNA, COII-16S and Nad5 mtDNA. The D2-D3 sequences had more than 99% identity with many sequences of tropical species. The COII-16S sequences had more than 99% identity with sequences of M. arenaria, M. morocciensis and M. thailandica. The Nad5 sequences had 99.81% identity with some sequences of M. arenaria. The D2-D3 and COII-16S sequences of M. arenaria did not form independent clades in corresponding Bayesian trees, but Nad5 sequences formed a monophyletic group in corresponding phylogeny. Based on this study, M. arenaria is present in Iran’s pistachio gardens, necessitating appropriate management measures.

Nothotylenchus savadkoohensis n. sp. was recovered from rotten wood samples of an unidentified forest tree in the Mazandaran province and described herein. It is mainly characterized by an elongated conoid tail ending in a sharply pointed tip and four lines in the lateral field. Females of the new species have 379–662 μm long bodies with 5.8–6.9 μm long stylets ending in fine posteriorly sloping knobs, the metacorpus not valvate, the pharyngeal bulb slightly overlapping the intestine, and the vulva at 76.5–84.0% of body length. Males are also common and have 13.0–14.5 μm long spicules and bursa cloacal. By having an elongated conoid tail and four lines in the lateral field, the new species comes close to four known species, namely N. acris, N. acutus, N. antricolus, and N. truncatus. The morphological differences between the new species and the abovementioned species are discussed. The new species was sequenced for its D2–D3 segment of LSU and ITS rDNA regions. In the LSU phylogenetic tree, the currently available LSU sequences of the genus Nothotylenchus occupied distant placements from each other and the LSU sequence of the new species formed clade with a sequence assigned to Neotylenchus sp. In ITS phylogeny, the newly generated sequence of the new species formed a clade with a clade that includes sequences of Ditylenchus sp. and Neomisticius platypi and N. variabilis.

Using integrated pest management without relying on chemical pesticides is one of the most attractive approaches to controlling plant pathogens. Among them, using resistant cultivars or rootstocks against diseases in combination with beneficial microorganisms has attracted special attention. The citrus nematode is one of the major constraints of citrus cultivation worldwide. We showed that the mycorrhizal arbuscular fungus, Funneliformis mosseae , increased growth parameters including shoot and root length and biomass of two main rootstocks of citrus, sour orange and Volkamer lemon, in noninfected and infected plants with citrus nematode. It decreased the infection rate by citrus nematode in both rootstocks compared with nonmycorrhizal plants. The rate of decrease in nematode infection was highest when plants were pre-inoculated with F. mosseae and was lowest when nematode was inoculated before F. mosseae. However, when nematode was inoculated before the fungus, the fungus was still able to mitigate the negative effect of infection by nematode compared with plants inoculated with nematode only. This suggests that the timing of inoculation plays a crucial role in the effectiveness of F. mosseae in reducing nematode infection. Moreover, monitoring of the expression of two genes, phenylalanine ammonia-lyase and β -1,3-glucanase , which are involved in systemic-acquired resistance (SAR) showed that although they were significantly upregulated in mycorrhizal plants compared with nonmycorrhizal plants, they showed the highest expression when plants were pretreated with fungus before nematode inoculation, thus, indicating that plants were primed. In summary, F. mosseae primes the defense-related genes involved in SAR, increasing plant defensive capacity and boosting growth parameters in citrus rootstock. This has important implications for the agricultural industry. [ABSTRACT FROM AUTHOR]

The article discusses the amendments made to the diagnosis of Ektaphelenchus cupressi, a species of nematode. The study was conducted in forests near Elimalat lake in Iran, where a population of E. cupressi was found in dead and rotten wood samples. The researchers compared the Elimalat population with previously described Ektaphelenchus species and confirmed its identity as E. cupressi through morphological and genetic analysis. The article provides detailed descriptions of the cephalic region, stylet, and female posterior body region of E. cupressi, highlighting the unique features that help distinguish this species. The research was supported by Tarbiat Modares University. [Extracted from the article]

Summary: Three populations of Pauronemoides siddiqii n. gen., n. sp. were recovered from three different locations in northwestern and northern Iran from bark and soil samples. The new genus was described and illustrated based upon morphological and molecular characteristics. Pauronemoides n. gen. belongs to the family Paurodontidae and is characterised by the medium-sized body, asymmetrical knobs in stylet base, stem-like extension into intestine, post-vulval uterine sac (PUS) absent or rudimentary, different tail tip shape between sexes, and bursa enveloping tail or reaching to the tail end. The type species, Pauronemoides siddiqii n. gen., n. sp., is mainly characterised by 752-1281 μ m body length in females and 660-1085 μ m in males, six equally-sized lips, stylet 9-11 μ m long with asymmetrical knobs, six incisures in lateral fields forming five bands, three of which (two outers and one central) are wider, and variably lengthened stem-like extension projecting into the intestine. Vulva situated posteriorly (V = 87.7-91.7%), PUS absent. Conical tail with widely rounded end, having a small mucron at tip in females, males with conical tail ending to a narrower tip and bursa enveloping tail completely. The type species of the new genus was compared with all known species of the genera Prothallonema , Paurodontus , Paurodontoides and Paurodontella. Pauronemoides siddiqii n. gen., n. sp. resembles Prothallonema macrocellum and P. mucronatum by having the bulb extension penetrating into the intestine, dimorphism in tail shape of both sexes and bursa enveloping tail, and Paurodontella iranica by tail shape dimorphism between sexes and bursa ending near tail tip. Therefore, the above-mentioned species are transferred to the new genus as Pauronemoides macrocellus n. gen., n. comb. (= Prothallonema macrocellum), P. mucronatus n. gen., n. comb. (= Prothallonema mucronatum) and P. iranicus n. gen., n. comb. (= Paurodontella iranica). In addition to morphological comparisons, molecular phylogenetic analyses were performed using two sequences of small subunit (SSU), and three partial sequences of D2-D3 expansion segments of the large subunit (LSU) rDNA, and the resulting topologies were discussed. [ABSTRACT FROM AUTHOR]

AbstractThe box tree moth (BTM), Cydalima perspectalis, and the fall webworm (FWW), Hyphantria cunea are two invasive forest pests in northern Iran. Entomopathogenic nematodes (EPNs) are usually compatible with integrated pest management programs. In this study, the efficacy of five isolates of EPNs was evaluated against the two pests in laboratory and field conditions. LC50 values of Steinernema carpocapsae (IRTabriz), S. feltiae (IRTabriz), S. feltiae (Entonem), Oscheius rugaoensis and Heterorhabditis bacteriophora (IRTabriz) were as follow: 44.8, 66.5, 113.8, 190.7 and 515.9 infective juveniles (IJs) larva−1 on the fifth instar larvae of BTM; and 75.2, 96.6, 131.0, 258.0 and 292.5 IJs larva−1 on fifth instar larvae of FWW, respectively in the laboratory tests 48 h post-treatment at 25 °C and 60% relative humidity. Under field conditions, the foliar applications of S. carpocapsae (IRTabriz), S. feltiae (IRTabriz), and S. feltiae (Entonem) at the rate of 106 IJs L−1 resulted in 36–58% mortality after 48 h against BTM and 15–52% mortality against FWW, respectively. The results demonstrate that EPNs are promising candidates for biocontrol of BTW and FWW. [ABSTRACT FROM AUTHOR]