Abbas Mohammadi

Morphological, Molecular and Phylogenetic Study of Filenchus aquilonius as a New Species for Iranian Nematofauna and Some Other Known Nematodes from Iran Based on D2D3 Segments of 28 srRNA Gene

Ziziphus zizyphus is very important crop in Iran. Because there isn’t any research of plant parasitic nematodes on Z. zizyphus, authors were encouraged to work on it. Nematodes isolated from the soil samples by whitehead method (1965) and permanent slides were prepared. Among the species Filenchus aquilonius is redescribed for the first time from Southern Khorasan province. F. aquilonius is characterized by lip region rounded, not offset, with fine annuls; four incisures in lateral line; Stylet moderately developed, 10-11.8 μm long with rounded knobs; Hemizonid immediately in front of excretory pore; Deirids at the level of excretory pore; Spermatheca an axial chamber and offset pouch; Tail about 120-157 μm, tapering gradually to a pointed terminus. For molecular identification the large subunit expansion segments of D2/D3 were performed for F. aquilonius to examine the phylogenetic relationships with other Tylenchids. DNA sequence data revealed that F. aquilonius had closet phylogenetic affinity with Irantylenchus vicinus as a sister group and with other Filenchus species for this region and placed them in one clade with 100% for bootstap value support. Phylogenetic position and additional information of other taxa in Tylenchidae from this region of Iran are included. . Evidence from the 28S gene strongly supports that Filenchus species are monophyletic. There is the first study of D2D3 segment of F. aquilonius and I. vicinus.

Aflatoxin-producing Aspergillus species from saffron field soils in the South Khorasan province of Iran

Abstract The aim of the present study was to isolate and identify Aspergillus species associated with saffron plants in the city of Birjand (South Khorasan Province, Iran) as well as to assess their aflatoxin B1 production. Sampling was performed during 2013–2014 crop season. Aspergillus species were isolated and purified using general and specific culture media. Growth rates and macroscopic and microscopic characteristics of the isolates were determined using yeast extract, Czapek yeast extract, malt extract and creatine sucrose agar media at 25 and 37 °C. DNA was extracted by the modified CTAB method and beta-tubulin, calmodulin and internal transcribed spacer genes were amplified and sequenced. Phylogenetic position of the isolates was determined against other Aspergillus species. Thin layer chromatography was used to investigate the production of aflatoxin B1 by Aspergillus isolates. Based on the morphological characteristics, shape and colour of the colonies, and sequencing results, the isolates belonged to Aspergillus terreus, A. flavus, A. flavipes and A. niger species. Only A. flavus isolates were aflatoxin B1 producers. We concluded that the soil of the studied saffron fields contained several species of Aspergillus, with A. flavus significantly affecting crop production through contamination of the crop by aflatoxin.

Fusarium species associated with Wheat crown and root tissues in the Eastern Iran

Abstract From 2012 to 2014, 70 isolates of Fusarium species were recovered from the wheat fields of Khosf, Giuk, Taqab, Amirabad, Mohammadieh and Bojd in the South Khorasan Province, Eastern Iran. Based on morphological characteristics, these isolates belonged to 14 Fusarium species. DNA of 23 isolates was extracted and their ribosomal ITS regions were amplified, sequenced and aligned with Fusarium species sequences of the GenBank. Among Fusarium isolates, the isolates belonging to F. solani (18.6%), F. acuminatum (12.9%), F. longipes (11.4%) and F. nygamai (10%) species had the higher frequencies. Other isolates from wheat crown and root were F. avenaceum, F. compactum, F. crookwellense, F. culmorum, F. diversisporum, F. equiseti, F. fujikuroi, F. javanicum, F. oxysporum and F. semitectum. This study is the first investigation of Fusarium species associated to wheat crown and root in the eastern desert area of Iran.

A checklist of the family Pratylenchidae Thorne, 1949 from Iran

The Family Pratylenchidae comprises nematodes that are capable of penetrating and feeding on internal root tissues. The list of Pratylenchidae species known from Iran is presented. The updated species list provides information on their morphometrics, referring to full or partial descriptions, associated plants, geographical distribution and references. The list includes 37 species belonging to five genera. Two species of Pratylenchus (P. sensillatus and P. wescolagricus) are new records for the Iranian nematofauna. Some information on these two and other known species is also provided.

Description of Basiria birjandiensis n. sp (Nematoda: Tylenchidae) from South Khorasan province with a checklist of the family Tylenchidae Örley 1880 from Iran

In order to identify plant-parasitic nematodes (family Tylenchidae Örley 1880) associated with Ziziphus zizyphus in Iran, 360 soil and root samples were collected from South Khorasan province during 2012-2014. Herein, a new species of Basiria and several known members of the family Tylenchidae are reported. B. birjandiensis n. sp. is characterized by short body length (584-748 µm [660.6±72.3]), lip region with flat apex, stylet 11-12 µm (11.3±0.5), excretory pore position varying from isthmus level to the middle of the basal bulb (78-91 µm from the anterior end of the body), post-vulval uterine sac 8-14 µm (10.7±1.9) long, filiform tail (151-181 µm, c= 3.7-4.2, c´= 14.3-17.2) and body annuli 0.5-1 µm (0.6±0.1) wide. A checklist of Tylenchidae species from Iran is also presented.

A simple method for detection of Phytophthora nicotianae from soybean soil

Abstract A high detection rate of Phytophthora nicotianae was obtained from the naturally infested soil of soybean fields. Air-dried soils were firstly moistened in a flask and then pre-incubated at 25 °C for 1-4 weeks before flooding with distilled water and baiting with soybean leaf disks for 6, 12, and 24 h. The baits were then thoroughly washed, flooded with 10-15 ml of distilled water in Petri-dishes and incubated under continuous fluorescent light for 72 h. Sporangia started to emerge from the margins of leaf disks. They were easily observed under the stereomicroscope. Pure culture of the fungus was obtained by spreading zoospore suspension on a 1.5% water-agar containing anti-bacterial antibiotics. This is the first report of recovery of P. nicotianae from naturally infested soybean soils using sensitive leaf disks of soybean (Williams cultivar) as bait in Iran. All isolates were determined to be A2 mating type.