Rostaniha
Year:2007 | Volume:8 | Issue:1|Papers Count:12

The Miankaleh Biosphere Reserve with a surface area of 68800 hectares is located in 12 km N of Behshahr (Mazandaran Province, N. Iran) between 53o 35' - 54o 2' eastern longitude and 36o 45' - 36o 55' northern latitude. The vegetation of Miankaleh Peninsula was studied, using the Braun-Blanquet (Zygmatist) method. Based on the analysis of phytosociological data using the Anaphyto software and AFC and CAH methods 26 associations were recognized. The following associations occupy the large part of the area: Punicetum granati, Junco maritimi - Rubetum sancti, Juncetum littoralis and Salicornietum europaea. The distribution of plant associations in the Miankaleh area is mainly influenced by the soil chemical factors including EC, Na+, Ca2+, Mg2+, Cl-, HCO3-, SO42- and water table.

In this research, the response of shoot and root of two cultivars of soybean (Glycine max L. cvs Gorgan 3 & Williams) to mild and severe drought was evaluated in pot. Two weeks after of planting, three irrigation treatments including every day (as control), once in three (as mild stress) and five days (as severe stress) were used. The results showed that, stem dry weight, stem and root length, internode number and leaf area were not different in mild and severe drought in two cultivars significantly but the amount of soluble sugars decreased in leaf. The content of chlorophylls a & b decreased in mild and severe stress in two cultivars. To increase stress the amount of total protein decreased in root, shoot and nodule and this decrease was more in Williams. K+ content in shoot and Na+ content decreased in roots of two cultivars in comparison to control.

In the present study, choromosome numbers of 10 species of the genus Cousinia including: C. bienerti (n=13), C. decipiens (n=13), C. deserti (n=12), C. esfandiari (n=13), C. komarowii (n=13), C. lepida (n=13), C. neurocentra (n=12), C. piptocephala (n=13), C. smirnowii (n=12) and C. turcomanica (n=13) are reported from Iran. Specimens have been collected from Semnan and Khorasan Provinces. Nine of the counts are new to science and one provides confirmation of the previous report. The chromosome numbers for three sections are reported for the first time.

Aflatoxins are the most serious problem in production and export of pistachio of Iran. They are amongst the most toxic mycotoxins and are produced predominantly by Aspergillus flavus and A. parasiticus. Pistachio is susceptible to invasion by aflatoxigenic Aspergillus species and subsequent production of aflatoxins, during preharvesting, processing, transportation or storage. Various methods have been used to detect toxin in pistachio such as chromatography (TLC and HPLC), ELISA and PCR base methods. Some of these methods e.g. chromatography, are time consuming, labor-intensive and expensive. In this study, nuts sample of pistachio were collected from pistachio orchards in Kerman, Rafsanjan and Isfahan. Culture media AFPA and PDA, were used to isolate Aspergillus species. Two hundred and fifty isolates were obtained and based on microscopic and macroscopic studies, the isolates belonged to the genera, Aspergillus, Fusarium, Rhizopus, Alternaria and Cladosporium. Comparing morphological characters of Aspergillus species grown on CYA, CY20S and MEA after one week, 10 following Aspergillus species were identified: A. alliaceus, A. candidus, A. flavus, A. niger, A. niveus, A. ochraceus, A. parasiticus, A. tamari, A. terreus, A. unguis and A. wentii, that A. alliaceus, A. candidus, A. niveus, A. unguis and A. wentii, were reported for first time from pistachio in Iran. There was not a direct relationship between sclerotium and aflatoxin production in this study. Application of methylated b-cyclodextrin in culture media showed that it can be used for rapid detection of aflatoxigenic aspergilli.

Three kinds of sclerotia of Typhula spp. from Ardabil, East Azerbaijan and Qazvin Provinces in the northwest of Iran were collected. Morphology and ITS sequences of rDNA suggested that the collected fungi belonged to Typhula incarnata Lasch, Typhula phacorrhiza (Reichardt) Fr. and Typhula sp. These three taxa are new records in the Middle East and the result of this research suggests that Iran is one of the southern limits of geographical distribution of sclerotium forming snow mould fungi.

Some 340 isolates belonging to Mucorales, obtained from rhizosphere of root knot nematode host plants in Chahar Mahal & Bakhtiari Province, were studied during 2003-5. Fourteen new taxa, namely, Absidia spinosa, Actinomucor elegans, Cunninghamella echinulata var. echinulata, C. echinulata var. nodosa, C. echinulata var. verticillata, Mucor circinelloides f. circinelloides, M. circinelloides f. lusitanicus, M. hiemalis f. luteus, M. inaequisporus, M. plumbeus, M. racemosus f. racemosus, M. ramosissimus, M. variosporus and Zygorhynchus heterogamus are recorded from Iran.

Some 800 soil and rotten wood samples were collected from Gilan, Mazandaran and Golestan Provinces in the north of Iran. By using selective and general media, 217 Trichoderma isolates were obtained belonging to sections Longibrachiatum (69 isolates) and Pachybasium (148 isolates), respectively. Pure cultures were obtained by single conidium and single chain methods. Colony features were recorded and microscopic examinations were carried out on 5-7 day old cultures on MA, PDA and OA media. Conidiophores, conidia and sporulation patterns were studied and recorded. Thirteen species of Trichoderma are identified among which T. ceramicum, T. crassum and Trichoderma sp. (sect. Pachybasium) and T. reesei, anamorph of H. andinensis and anamorph of H. orientalis (sect. longibrachiatum) are new records to the mycofolora of Iran.

Species belonging to different sections of the genus Polygonum L. were studied micro-morphologically. For this purpose, digital images were obtained from all species and lower taxa belonging to sections Persicaria, Bistorta, Tiniaria and Pleuropterus. Since section Polygonum is much diverse, pollens of three representative species Polygonum luzuloides, P. olivascens and P. setosum were photographed by Scanning Electron Microscopy (SEM). Based on SEM studies shape, size, ornamentation of exine and porate/colpate pollens are considered diagnostic for separating the sections from each other. An identification key to the section Persicaria is presented and section is to be promoted to genus level.

In the framework of study on wood inhabiting Hyphomycetes in Chalus vicinity, Mazandaran (Iran), during 2005-2006, 21 taxa belonging to different genera were identified. Among them, nine taxa have already been recorded from Iran and the other taxa are new to Iran which are listed as follows:Arthrobotryum stilboideum, Chloridium preussi, C. virescens var. virescens, Codinaeopsis gonytrichoides, Dactylaria purpurella, Geniculosporium state of Hypoxylon serpens, Oncopodiella trigonella, Pleurothecium recurvatum, Pseudospiropes hachijoensis, Sporidesmium folliculatum, Taeniolella subsessilis and Zygosporium gibbum.

In this research, five species of genus Polystichum, belong to Aspidiaceae, namely, P. lonchitis, P. woronowii, P. setiferum, P. braunii and P. aculeatum, gathered from Gilan and Mazandaran Provinces were anatomically studied. To distinguish anatomical character of different growing organs such as pinnules, rachis, rhizumes and roots, the cross section was prepared. Based on these researches, identification key was made and the results were shown with most differences in shape and size of xylem in rachis sections.