An updated and annotated checklist of the Tylenchulidae (Nematoda: Criconematoidea) of Iran

Ghaderi, Reza, Karegar, Akbar, Miraeiz, Esmaeil, Hesar, Abbas Mokaram (2019): An updated and annotated checklist of the Tylenchulidae (Nematoda: Criconematoidea) of Iran. Zootaxa 4545 (2): 205-229, DOI: https://doi.org/10.11646/zootaxa.4545.2.

FIGURE 7 in An updated and annotated checklist of the Tylenchulidae (Nematoda: Criconematoidea) of Iran

FIGURE 7. Diagnostic characters of Paratylenchus similis from Iran. Female (A–L). A & B: Body posture; C–F: Anterior end; G–I: Vulval region; J–L: Posterior end. (Scale-bars: A & B = 50 µm; C–L = 10 µm)

Characterisation of Ditylenchus paraoncogenus n. sp. (Nematoda : Anguinidae), a new stem nematode parasitising tumble thistle

During a survey, three populations of a new stem nematode were isolated from galls on the shoots of tumble thistle (Gundelia tournefortii) plants in Fars province, Iran, and identified. Ditylenchus paraoncogenus n. sp. is described based on morphometric and morphological characters. It is characterised by having long-sized females, 1252 (943-1628) μm long, narrow lateral fields with six incisures, rather developed stylet 9.9 (9.0-11.3) μm long with round knobs, usually elongate and offset from intestine basal pharyngeal bulb, oocytes in two rows in distal part of ovary, V = 83.3 (80.3-86.2), post-vulval uterine sac 68.1 (46.9-86.1)% of vulva to anus distance long, bursa covering 63.2 (33.3-74.4)% of tail length, spicules 24.7 (21.0-27.9) μm long with minute processes at the base of its manubrium and anteriorly pointed cuticle parts within the lamina, and thick conical tail, usually with a pointed terminus. In addition, the ITS and 18S rDNA sequences of 17 populations of D. destructor, D. dipsaci, D. medicaginis, D. myceliophagus, D. paraoncogenus n. sp., Ditylenchus sp. and Nothotylenchus geraerti plus one population of Anguinidae sp. were analysed. The results showed a close relationship between D. paraoncogenus n. sp. and the stem nematodes D. oncogenus, D. gigas, D. weischeri and D. dipsaci. Ditylenchus species were divided into two clades, one clade comprising stem nematodes and gall-forming nematodes of the family Anguinidae, and the other clade containing fungivorous species. Observations showed that the second-stage juvenile is the dormant stage of D. paraoncogenus n. sp. and can survive in anhydrobiotic condition for at least 4 years

Is the Arbuscular Mycorrhizal Fungus <i>Funneliformis mosseae</i> a Suitable Agent to Control Criconematid Populations?

Several studies have shown the potential of using mycorrhizal fungi in increasing the plant yield by simultaneously reducing damages caused by pathogens. Plant parasitic nematodes (PPNs) are among the most feared pathogens for crops. This study aimed to evaluate the effects of Funneliformis mosseae as a mycorrhizal fungus on the population abundance of three world widespread species of nematodes from the family Criconematidae: Mesocriconema xenoplax, Mesocriconema antipolitanum, and Criconemides informis. Pure and highly abundant populations of each species were collected from Urmia city in Northwestern Iran, after the identification morphological and morphometric characteristics. The experiments were carried out in greenhouse conditions on three different rhizospheres of alfalfa, sugar beet, and wheat. After five months, the final population of nematodes and fungus, and the root surface on host plants inoculated and non-inoculated with the fungus F. mosseae, were evaluated. The results showed that the population of nematodes was increased in the presence of the fungus. It could be assumed that the extension of the host surface level of roots by the fungus resulted in more feeding sites for nematode activity and, consequently, higher population densities. In this study, the fungus did not seem to play a suitable role in controlling ectoparasitic nematode growth. However, since there are still many open questions about mycorrhizal fungi’s role in agriculture, more research should be conducted

Population Genetic Structure of Meloidogyne javanica Recovered from Different Regions of Iran

In a survey of root-knot nematodes in Iran, twenty-nine populations were collected from eleven provinces. All populations were identified as Meloidogyne javanica based on morphological and morphometric characteristics of females, males, J2s, and perineal patterns. Sequence Characterized Amplified Region (SCAR) primers confirmed the morphological studies, and all these populations produced a specific band in 670 bp using Fjav and Rjav primers. Genetic structure analyses using the combination of RAPD and ISSR markers revealed four different groups, which was in agreement with UPGMA cluster analyses. These four groups were related to four different geographic regions with a high geographic distance. The total estimated genetic diversity was 8%, which was a low value. Values of FST and Nm were 0.628 and 0.148, indicating that populations of these four regions were separated from each other; however, some gene flow between them could be attributed to human activities. Mantel test also revealed a negative correlation between genetic diversity and geographic distance