Summary Basilaphelenchus persicus n. gen., n. sp. is described and illustrated based on morphological and molecular phylogenetic studies. The new genus belongs to the family Aphelenchoididae and is characterised mainly by the small body size of females (297-393 μm) and males (304-331 μm), high cephalic region in both sexes, fine 5.5-7.8 μm long stylet that is barely visible in mounted specimens yet clear in fresh individuals, stylet with a linear conus and weak shaft ending in three elongate, posteriorly directed, knobs, small spherical metacorpus with posteriorly located (at 72-75% of metacorpus) weak but distinct valve, monodelphic-prodelphic reproductive system with a long post-vulval uterine sac containing large rounded sperm cells, a vulva lacking any flap apparatus, conical tail of female usually ventrally bent at tip and male tail ventrally bent as in the female, lacking the P1 supplement, but with three pairs of caudal papillae, and small arcuate spicules with rounded condylus and small pointed rostrum. The new genus is similar to both Tylaphelenchus and Pseudaphelenchus in the possession of a raised cephalic region and a small spherical metacorpus, placing it in the subfamily Tylaphelenchinae. It is also typologically similar to Aphelenchoides. Molecular phylogenetic studies using both SSU and LSU rRNA gene sequences (both partial) revealed that the new genus formed a robustly supported sister clade with Pseudaphelenchus spp. and had a basal placement to this clade and, probably, to all other aphelenchoidids. Tylaphelenchus grosmannae is transferred to the new genus as B. grosmannae n. comb. and A. christinae n. comb. (= T. christinae) is proposed. The taxonomic status of Tylaphelenchus is discussed and T. sinodendroni n. comb. (= A. sinodendroni) proposed.

Background Sugar beet (Beta vulgaris subsp. vulgaris) is an economically important crop that provides nearly one third of the global sugar production. The beet cyst nematode (BCN), Heterodera schachtii, causes major yield losses in sugar beet and other crops worldwide. The most effective and economic approach to control this nematode is growing tolerant or resistant cultivars. To identify candidate genes involved in susceptibility and resistance, the transcriptome of sugar beet and BCN in compatible and incompatible interactions at two time points was studied using mRNA-seq. Results In the susceptible cultivar, most defense-related genes were induced at 4 dai while suppressed at 10 dai but in the resistant cultivar Nemakill, induction of genes involved in the plant defense response was observed at both time points. In the compatible interaction, alterations in phytohormone-related genes were detected. The effect of exogenous application of Methyl Jasmonate and ET-generator ethephon on susceptible plants was therefore investigated and the results revealed significant reduction in plant susceptibility. Genes putatively involved in the resistance of Nemakill were identified, such as genes involved in phenylpropanoid pathway and genes encoding CYSTM domain-containing proteins, F-box proteins, chitinase, galactono-1,4-lactone dehydrogenase and CASP-like protein. Also, the transcriptome of the BCN was analyzed in infected root samples and several novel potential nematode effector genes were found. Conclusions Our data provides detailed insights into the plant and nematode transcriptional changes occurring during compatible and incompatible interactions between sugar beet and BCN. Many important genes playing potential roles in susceptibility or resistance of sugar beet against BCN, as well as some BCN effectors with a potential role as avr proteins were identified. In addition, our findings indicate the effective role of jasmonate and ethylene in enhancing sugar beet defense response against BCN. This research provides new molecular insights into the plant-nematode interactions that can be used to design novel management strategies against BCN.

Filenchus annulatus is redescribed and males are characterised for the first time based on a population found in Northem Khorasan province, Iran. New morphological characterisation is based on light and scanning electron microscopy. In addition, molecular analyses based on 18S and 28S genes are included to test monophyly of the genus. Females from the Iranian population have a spermatheca typically filled with sperm. Generally males are similar to females, ranging from 306 to 426 ßm long. Spicules are arcuate, cephalated and 11.5-14.0 ßm long, the gubernaculum is minute and trough-shaped and the caudal alae are adanal. Phylogenetic analyses differed in results depending on the gene used: 28S gene strongly supports Filenchus as monophyletic whereas 18S shows Filenchus as polyphyletic. In both gene phytogenies, F annulatus is placed as a sister taxon of F quartus from Wyoming, USA. Although sequence divergence between these two species is only 3 base pairs and 1 base pair for 28S and 18S genes, respectively, strong morphological differences support their species status. Relationships between Filenchus and other Tylenchidae genera are also gene dependent. Such differences in tree topologies and branch support are related to the number of Filenchus species used in the analyses (greater for 18S gene) and gene resolution (greater for 28S gene). Molecular phytogenies also suggest that other Tylenchidae genera {i.e., Fsilenchus, Cephalenchus and Futylenchus) belong to separate clades, as is also suggested by some morphology-based classifications. The inclusion of more taxa and perhaps additional genes is needed further to clarify Filenchus relationships and further to test its monophyly.

Thirteen species of Pratylenchidae: Pratylenchus coffeae, P. delattrei, P. loosi, P. neglectus, P. penetrans, P. pseudopratensis, P. thomei, P. vulnus, Pratylenchus sp., Pratylenchoides alkani, P. ritteri, Hirschmanniella sp. and Zygotylenchus guevarai were collected from different crops and plants throughout Iran. The specimens were identified using morphological and molecular methods. Morphometrics and morphology are given for Pratylenchus sp., P. delattrei, Pratylenchoides alkani and Hirschmanniella sp. The D2-D3 expansion segments of the 28S rRNA gene were amplified and sequenced for all 13 species studied. Diagnostic PCR-ITS-RFLP profiles are given for Pratylenchus delattrei, P. penetrans, P. pseudopratensis, Pratylenchus sp., Pratylenchoides alkani and P. ritteri. Pratylenchus neglectus and P. thomei, collected from cereal fields, P. loosi from tea plantations, P. coffeae from banana, P. penetrans from ornamental plants, P. vulnus from pines and Z. guevarai from almonds showed a high level of similarity in the D2-D3 sequences with corresponding GenBank sequences. Nucleotide differences between Iranian populations and reference species were in the intraspecific range. Pratylenchus delattrei, found in vegetable fields, and Pratylenchus sp. from palm rhizosphere, formed a highly supported clade with P. zeae, the two former species being morphologically very close to the latter except in tail shape. Pratylenchus pseudopratensis, from cereal fields, clustered with P. vulnus with low support. Phylogenetic relationships within Pratylenchus species were mainly congruent with those obtained in previous studies. Despite the morphological similarities between P. ritteri and P. alkani, the D2-D3 of 28S rRNA gene sequences differed by 5 bp. Hirschmanniella sp., from a rice field, formed a clade with H. loofi and H. kwazuna.

Potential of Oyster Mushrooms for the Biocontrol of Sugar Beet Nematode (Heterodera Schachtii)The potential of oyster mushrooms to attack and kill sugar beet cyst nematode (Heterodera schachtii) was studied. The ability ofPleurotus ostreatus, P. sajor-caju, P. florida, P. flabellatus, P. ostreatus(sporeless),P. eryngiiandHypsizygus ulmariusto prey on the cyst nematode was confirmed. Nematodes were inoculated on water agar plates on which a single sparse fungal colony of one of the above mentioned fungi was grown. Nematodes were quickly immobilized after inoculation the plates with eachPleurotusspecies, with mortality of about 96%, 72%, 55%, 52%, 20%, 23% and 62%, respectively. Nematicidal activities of culture filtrates ofPleurotusspecies andH. ulmariusagainstH. schachtiiwere also studiedin vitro.Extracts ofP. ostreatuscould paralyse 90% of nematodes whereasP. eryngiicould paralyse only 50% of nematodes. The efficacy of old mushroom compost from cultures ofP. ostreatusandP. sajor-cajuin controlling cysts on sugar beet (Beta vulgarisICI) were studied under greenhouse conditions. The results showed that 100 and 200 grams of mushroom compost per 3 kilogram/pot could significantly control cysts, reducing more than 85% cysts in soil. Presence of cysts on the roots and larvae inside roots were compared with the control treatment.