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Plant-parasitic nematodes significantly reduce crop production. The stem and bulb nematode (Ditylenchus dipsaci) is one of the important pathogen of several ornamental and field crops including alfalfa. In this study, the reactions of seven alfalfa ecotypes to the nematode were investigated under greenhouse conditions. The experiment was conducted based on completely randomized design with three replicates. The results showed significant differences (P<0.05) among inoculated ecotypes with the nematode in all morphological traits (except of root length) compared to the control. The nematode reproduced in all studied alfalfa ecotypes, but the rate of reproduction was different. The highest reproduction factor (RF) was observed on the ecotype Neishabouri (RF = 7.14) and the lowest on Feiz and Hamedani with reproduction factors of 1.24 and 1.85, respectively. The highest number of the nematode was observed in stems, rhizosphere and buds. The results showed that none of these ecotypes were resistant or tolerant to the stem and bulb nematode. [ABSTRACT FROM AUTHOR]

For identification of nematode species of the genera Ditylenchus and Nothotylenchus, 341 plant and soil samples from farms, orchards and pastures of Fars, Kohgiluye and Boyer-Ahmad, Bushehr and Hormozgan provinces, and 32 samples from Mazandaran, Golestan, Hamadan, Lorestan and Ilam provinces were collected, during 2013-2016. After extraction, killing and fixing, the extracted nematodes were transfered to anhydrous glycerol. Species identification was done using light microscope equipped with digital camera, based on morphometric and morphological characters. The results showed that the genera were existed in 54.7% of the samples. In this study, 12 species of Ditylenchus and five species of Nothotylenchus were identified. D. myceliophagus and D. medicaginis with 38.8% and 38.1% frequency, respectively, and N. geraerti with 60% frequency were the most common species. The species N. basiri, D. geraert and D. solani are new records and were described for the first time from Iran. Moreover, descriptions of N. adasi and N. medians, and the identification key for the Iranian species of the genera Ditylenchus and Nothotylenchus were provided. [ABSTRACT FROM AUTHOR]

In order to identify the plant parasitic nematodes of the families Dolichodoridae and Pratylenchidae (Nematoda: Tylenchomorpha) collected from green space and gardens in Shiraz, Iran, 67 soil and root samples were collected from different localities of the region during 2014-2015. The nematodes were extracted, fixed and transferred to glycerin according to the De Grisse method. The permanent slides were prepared from the extracted nematodes and studied by light microscope. In this study 15 species namely Amplimerlinius globigerus, Merlinius brevidens, Trophurus pakendorfi, Tylenchorhynchus clarus, T. dubius, T. iphilus, T. mashhoodi, T. teeni, Pratylenchus ekrami, P. thornei, P. unzenensis, Zygotylenchus guevarai, Helicotylenchus digonicus, H. pseudorobustus and Rotylenchus buxophilus were identified. The species T. pakendorfi, T. iphilus and P. ekrami as new records of Iranian nematode fauna, along with P. unzenensis are redescribed. [ABSTRACT FROM AUTHOR]

Among plant-parasitic nematodes collected from fields, orchards, meadows and grasslands of the primarily seven southern provinces of the country viz. Fars, Sistan and Baluchistan, Hormozgan, Khuzestan, Kohgiloyeh and Boyer-Ahmad, Kerman and Bushehr; 13 species of the subfamily Telotylenchinae of the genera Bitylenchus, Neodolichorhynchus, Paratrophurus, Trophurus and Tylenchorhynchus were identified morphologically. Three species, N. phaseoli, Trophurus impar and Tylenchorhynchus qasimii, are new records for Iranian nematofauna. Description, morphometric data and line drawings provided for the above three species, as well as three other poorly known telotylenchids in Iran. Furthermore, Tylenchorhynchus variannus considered as a junior synonym of T. clarus here. [ABSTRACT FROM AUTHOR]

Potato cyst nematode, Globodera rostochiensis was reported from potato fields of Bahar County in Hamadan Province in 2008. In order to determine the pathotype of potato cyst nematode, ten populations of potato cyst nematode were collected from different potato fields in Bahar regions. Species identification was based on the morphological and morphometric characters of second stage juveniles and cysts, and by using speciesspecific primers and nucleotide sequences of the D2-D3 expansion segments of the 28S rRNA gene. Four potato cultivars viz Désirée, Marfona, Sante and Agria were used for pathotype determination, in pot experiments. The plants were treated by 6 ± 1 eggs and second stage juveniles and maintained in growth chambers at 18-22°C for three months. Based on the results of resistance assessment and relative susceptibility of the tested cultivars the pathotype of the populations was determined as Ro1. The obtained sequences were compared through BLAST search from the NCBI and the phylogenic tree was depicted. The impact of susceptible cultivars Marfona, Désirée, resistant cultivars sante, and Agria on egg hatching indicated that there is no significant difference among the cultivars in most pot experiments and all the cultivars were placed in the same statistical groups. [ABSTRACT FROM AUTHOR]