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Tanha Maafi Z.,Iranian Research Institute of Plant Protection | Subbotin S.A.,Plant Pest Diagnostic Center | Subbotin S.A.,RAS A.N. Severtsov Institute of Ecology and Evolution | Pourjam E.,Tarbiat Modares University | And 2 more authors.
Nematology | Year: 2013

Thirteen species of Pratylenchidae: Pratylenchus coffeae, P. delattrei, P. loosi, P. neglectus, P. penetrans, P. pseudopratensis, P. thornei, 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. thornei, 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. © 2013 Koninklijke Brill NV, Leiden.

Since 2004, an undescribed species of Unaspis (Hemiptera: Diaspididae) has become a damaging pest on Lansium domes-ticum Corrêa in the Philippines. Its attack on the leaves causes premature senescence and defoliation, resulting in the pro-duction of few, underdeveloped, sour fruit and sometimes killing the trees. The scale was misidentified initially as Lepidosaphes ulmi (Linnaeus) and then as Unaspis citri (Comstock), but further study indicated that it was an undescribed species of potential plant quarantine significance. The pest is described as U. lansivora sp. n. and an identification key to all 19 species of Unaspis is provided. Its distribution, host range and prospects for its biological control are discussed. © 2015 Magnolia Press.

Nephepeltia flavipennis (Holotype: Brazil, Rondônia, Governador Jorge Teixeira Municipality, Fazenda Rancho Grande, 10°31′48″S, 62°48′0″W, 165 m, J. Wiseman leg., in MNRJ) is described from the Amazon region of W Brazil, Ecuador, and N Peru. A lectotype is designated for N. aequisetis Calvert, 1909. Nephepeltia chalconota is considered to be a junior subjective synonym of N. flavifrons Karsch, 1889, and the subdivision of N. phryne into two subspecies is found to be unjustifiable. Diagnoses, illustrations, a key to males, and an updated map for all known members of the genus are provided. Copyright © 2014 Magnolia Press.

Watson G.W.,Plant Pest Diagnostic Center | Marler T.E.,University of Guam
Communicative and Integrative Biology | Year: 2014

Cycad aulacaspis scale (CAS, Aulacaspis yasumatsui, Hemiptera: Diaspididae) was accidentally introduced to Guam in 2003, and has caused acute mortality of the dominant, endemic forest tree Cycas micronesica. A phytotoxic legacy in the soils beneath cycad trees killed by CAS over a period of about three years has been demonstrated. The origin of the toxicity may be large quantities of CAS-encrusted cycad leaf litter. We explore the possibility that a major contribution to this toxic legacy may come from the scale insects, not just from the plant material. © 2014 Landes Bioscience.

Subbotin S.A.,Plant Pest Diagnostic Center | Subbotin S.A.,RAS A.N. Severtsov Institute of Ecology and Evolution | Rogozhin E.A.,RAS Shemyakin Ovchinnikov Institute of Bioorganic Chemistry | Chizhov V.N.,RAS A.N. Severtsov Institute of Ecology and Evolution
European Journal of Plant Pathology | Year: 2014

The needle nematodes of the genus Longidorus can cause diseases of various crops and trees, and are comprised of more than 150 valid species. Eleven valid and six unidentified species of the genus Longidorus collected in different regions of Russia, two states of USA, Germany, New Zealand and Ukraine were molecularly characterized using analysis of the partial 18S rRNA and the D2-D3 expansion segments of the 28S rRNA gene sequences. Fifty-four partial 28S rRNA and fifteen partial 18S rRNA gene sequences were obtained for the present study. Using molecular criteria, we confirmed the morphological identification and distinguished between the following species: L. aetnaeus, L. africanus, L. andalusicus, L. artemisiae, L. caespiticola, L. distinctus, L. elongatus, L. euonymus, L. intermedius, L. leptocephalus and L. lignosus. Two longidorid populations from Russia and four from California were not identified to a species level. We obtained the full length D2-D3 of 28S rRNA gene sequence from several freshly-collected L. artemisiae samples. We confirmed the identity of the D2 region of 28S rRNA gene sequence with a short D2 of 28S rRNA gene fragment sequence previously obtained from formalin-fixed nematodes embedded in the L. artemisiae paratype slides. Longidorus lignosus was molecularly characterized and L. aetnaeus was reported from Russia for the first time. PCR-D2-D3-RFLP diagnostic profiles generated by five restriction enzymes: AluI, HinfI, Bsp143I, Tru1I and RsaI are presented for sixteen Longidorus species. © 2013 KNPV.

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