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    First report of Heterodera hordecalis, a cereal cyst nematode, on wheat in Algeria
    (Amer Phytopathological Soc, 2018) Smaha, Djamel; Mokrini, Fouad; İmren, Mustafa; Mokabli, Aissa; Dababat, Abdelfattah A.
    The cyst nematodes (Heterodera spp.) are a major group of plant-parasitic nematodes that attack many crop species and cause serious yield losses in major food crops (Jones et al. 2015). Nematodes in the genus Heterodera occur in all major cereal production areas in the Mediterranean Basin (Dababat et al. 2015). In June 2016, six soil samples were collected from durum wheat (Triticum durum) fields of Guellal (36°2'7" N; 5°20'12" E), Hammam Sokhna (35°58’60" N; 5°48’0" E), Ain Arnat (36°10’60" N; 5°19’0" E), Seriana (35°41’37'' N; 6°11’12'' E), Sebaine (33°39’0'' N; 0°12’0'' E), and Maghnia (34°51’42" N; 1°43’50" W), located in the Algerian provinces of Setif, Batna, Tiaret, and Tlemcen. The surveyed wheat fields had stunted patches, poor plant growth, chlorotic lower leaves, and few or no tillers. Cysts were extracted from the soil using a Fenwick Can technique (Fenwick 1940) and identified. Morphologically, cysts were rounded, deep yellow to brown, with a thick subcrystalline layer, small vulval cone, bifenestrate, two almost circular semifenestrates separated from each other by a rather wide vulval bridge, vulval slit obviously covered by a flap, and bullae present at the underbridge level. Cysts also displayed a strong underbridge with pronounced thickening in the middle and bifurcation at both ends.
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    First report of the cereal cyst nematode (Helerodera filipjevi)-on wheat in Algeria
    (Amer Phytopathological Soc, 2018) Smaha, Djamel; Mokrini, Fouad; İmren, Mustafa; Mokabli, Assia; Dababat, Abdelfattah
    Cereal cyst nematodes (CCNs) are an important group of sedentary plant-parasitic nematodes that restrict production of cereal crops throughout the world (Smiley et al. 2017). Heterodera filipjevi is considered one of the most destructive Heterodera species and causes significant damage in global wheat production (Dababat et al. 2015). In April 2016, two populations of cyst nematode were collected from Lamtar (35°4′4″ N; 0°47′53″ W) and Telagh (34°47′6″ N; 0°34′23″ W) wheat (Triticum durum) fields of Sidi Bel Abbes province in Algeria. The wheat fields had stunted patches, poor plant growth, chlorotic lower leaves, and few or no tillers. Cyst extraction from soils taken from the Lamtar and Telagh fields resulted in 9 and 11 cysts per 100 cm3 of soil, respectively. The cysts were extracted from soil using a Fenwick can technique (Fenwick 1940) and identified by morphology and morphometric analysis as well as by internal transcribed spacer (ITS)-rDNA sequencing. Morphologically, the cysts were lemon shaped with a posterior protuberance. The vulval cone was bifenestrate with horseshoe-shaped semifenestra and had strongly developed bullae and an underbridge.
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    Morphological and molecular identification of cyst nematode species (Heterodera spp.) in Algerian cereal fields
    (Polish Academy of Sciences, 2019) Smaha, Djamel; Mokrini, Fouad; İmren, Mustafa; Mokabli, Aissa; Dababat, A. Dababat
    Cereal cyst nematodes (Heterodera spp.) are distributed globally and cause severe production losses of small grain cereals. To investigate the occurrence of cereal cyst nematodes in wheat-growing areas of Algeria, a survey was conducted and 27 cereal cyst nematode populations were collected. The populations were initially identified based on their morphological and morphometric characters, followed by molecular methods using species-specific primers, complemented by ITS-rDNA sequences. The morphological and morphometric features of second-stage juveniles (J2s) and cysts supported the presence of three Heterodera species: H. avenae, H. filipjevi and H. hordecalis. All morphological values of these distinct populations were very similar to those previously described for these species. Using species-specific primers for H. avenae and H. filipjevi, the specific bands of 109 bp and 646 bp confirmed the morphological identification of both species, respectively. In addition, the internal transcribed spacer (ITS) regions were sequenced to study the diversity of the 27 populations. These sequences were compared with those of Heterodera species available in the GenBank database (www.ncbi.nlm.nih.gov) and re-confirmed the identity of the species. Nineteen sequences of ITS-rDNA were similar (99–100%) to the sequences of H. avenae published in the GenBank, six sequences were similar (99–100%) to H. hordecalis, and two were similar (98–99%) to H. filipjevi. The results of this study are of great value to breeding programs and extension services, where they will contribute to the design of control measures to keep damaging nematodes in check. © 2019 Polish Academy of Sciences. All rights reserved.