Rostaniha
Year:2011 | Volume:12 | Issue:2 (41)|Papers Count:14

Cyanophyta of some paddy-fields of Golestan province (North of Iran, near the Caspian Sea) have been studied during 2006–07. Phormidium subinerusatum, P. tenue, P. jadinianum, P. purpurascens, P. lucidum, P. fragile, Microcoleus palaodus, M. lacustris are new records for Golestan province and Iran. Results showed that P. subinerusatum, P. tenue were dominant in all stations. P. fragile, in spring and M. palaodus, M. lacustris, in autumn and winter were not visible in any station. Morphological characteristics of these species are described in detail and information about their ecological distribution is provided.

Nitrogen fixation blue-green algae make a major contribution to the fertility of soil. It has been suggested that blue-green algae (BGA) assist higher plant growth by supplying growth substances. There are numerous works about roles of blue-green algae in paddy soils and rice growth but little on other plants. In this research, 19 morphospecies belonging to three families of heterocystous and non-heterocystous blue-green algae from several paddy fields in the north of Iran were identified out of which seven species are new to Iran. Among these taxa, three species were used as inoculum in pot culture of cucumber, tomato and squash. The result revealed that addition of all algal extracts can enhance seed germination and plant growth in all treated plants. Statistical analysis showed that there are significant differences in plant height, root length, number of leaves, fresh and dry weight of root, leaf and stem as compared to control.

Iran is a mountainous country. Hezar Mt., is an isolated mountain with the highest peak of 4465 m (above sea level) located in southeast of Iran. This paper aims to provide a general overview of alpine phytodiversity of Hezar Mt. Alpine regions are above timber-line which is dependent on the climate, slopes and human activities. The timberline at Hezar Mt., is varying from 3200 m (North slope) to 3, 350 m (South slope). In this study, 208 species belonging to 122 genera and 39 families are known from the subalpine and alpine zone of Hezar. Hemicryptophytes dominate in the alpine belt (67%) and chamaephytes constitute 15% of the alpine flora, most of them are thorny cushions. Species number declines remarkably with increasing altitude whereas proportion of endemism is increasing. The altitudinal maximum record for the flowering plants is 4450 m. The phytogeographical analysis shows that about 46% (97 species) of the alpine flora of Hezar are Iranian endemic and subendemic and the origin of alpine flora of Hezar is Irano-Turanian. Some useful alpine species and some threatening factors to environment are also mentioned.

Weed species Anoda cristata, Ipomoea hederacea, and I. triloba are reported for the first time for the flora of Iran. Trianthema portulacastrum, and Merremia dissecta, which have been previously reported as a doubtful and an ornamental species respectively from non-agricultural areas, are recorded for the first time from arable and farmlands of the country. Exact localities, crops, distribution, illustrations and brief description are given for each species.

In the present study, a modelling approach based on Geographical Information Systems (GIS) analysis is presented with the aim of identifying the influence of environmental parameters on three genera, namely, Tortula, Grimmia and Bryum as representatives of Iranian bryoflora. By using ArcGIS Desktop, we produced a model for environmental variables include altitude, precipitation, temperature and humidity. To test the model, we surveyed the effect of selected geographical and environmental variables including altitude, latitude, annual mean precipitation, maximum, minimum, and mean temperatures and humidity on distribution pathern of these three genera. Within 108 localities, 52 samples of Bryum (48%), 33 samples of Grimmia (30%) and 24 samples of Tortula (22%) were recorded. The digital models that we achieved revealed interesting results. Altitude map shows strong preference within three genera for mountainous regions. Almost all species limited to the regions received proper amount of average rainfall. Temperature digital map shows a negative relationship between temperature and bryophytes distribution. Modelling the four environmental parameters of Iran provides the means for a quantitative analysis of the distribution and abundance of vegetation types in every selected area, thus also allowing quantification and prediction of environmental effects on vegetation distribution. Itstimulates the use of GIS in botanical investigations by putting a collection of free, relevant, high quality formatted data into the hands of botanical researchers.

In the present study, the cyanobacterial flora of Urmia Lake (NW Iran), one of the largest salt lakes in the world and adjacent rivers is investigated. Urmia Lake comprises different micro-organisms including cyanobacteria which have a major role in aquatic ecosystems. Cyanobacterial samples were collected in 2008–09 from Urmia Lake and its surrounding ecosystems. All samples were cultivated, isolated and identified using morphological keys basically and also molecular methods via 16S rRNA sequencing in some cases. Following cyanobacterial species were isolated from Urmia Lake: Spirulina maxima, Gloeocapsa sp., Oscillatoriasp., Nodularia spumigena, Phormidium fragile, Oscillatoria salina, Plectonema notatum, Aphanocapsa grevillei, Trichormus variabilis, Lyngbya sp., Phormidium sp., Microcoleus chthonoplastes, Leptolyngbyasp., Chroococcus turgidus, Microcoleus sp., Chroococcus dispersus, Nodularia sp. and Nostoc sp.. These variations may be referred to limited sampling, or increased salinity of the lake during recent years that has eliminated some non-tolerant species. This study reflects the biologically activation of Urmia Lake despite the hypersalinity and extreme condition of it.

The chromosome number (2n=5x=44+1B) of Tanacetum fisherae, as a new record from high mountains of southern Iran (Kerman province: Hazar mountain) is reported. A new ploidy level (pentaploidy) for the genus is presented for the first time. The studied population was aneuploid, having lost one chromosome out of the 45 expected in an x=9-based pentaploid. The distribution map, description and micromorphological characteristic of the achene are given. A taxonomic conclusion on the basis of molecular data and phylogenetic position of T. fisheraeis also discussed.

A new species of Astragalus is described: Astragalus barnasariformis sp. nov., Maassoumi, F. Ghahrem. & Bagheri. It is endemic to Zanjan province in northwestern Iran. Morphological evidence supports taxonomic placement of the new species in Astragalus sect. Trachycercis. The species appears to be most closely related to A. barnasari Grossh. and A. chalilovii.

A new Anthracoidea species, A. songorica, is described on Carex songorica (subgen. Carex, sect. Paludosae) from Iran.

A new smut fungus, Urocystis phalaridis, is described on Phalaris sp. (Poaceae) from Iran.

During 2009-10, cheese samples were collected from shops and cheese factories in Fars and Khuzestan provinces. Isolates were recovered from cheese using malt extract agar (MEA) and potato dextrose agar (PDA).

During 2009-10, the presence of ascomycetous species in soil was studied in Fars province. Isolates were recovered from soil using modified Czapek (Raperet al.1973), malt extract agar (MEA) and potato dextrose agar (PDA). Teleomorphic characteristics such as morphology of ascocarps, asci, ascospores and anamorphic characteristics such as conidiophores, phialides, conidia and chlamydospores were investigated. Based on the above criteria two species were identified: Emericella echinulata and E. nidulansfrom which the former species is a new record for Iran.

In reviewing of Poaceae family specimens in "IRAN" Herbarium, Urochloa panicoides belonging to Paniceaetribe and Eragrostis cilianensis (All.) Vign.-Lut. ex Janchen subsp. starosselskyi (Grossh.) Tzvelev to Eragrostideae tribe are reported as new to Iran. The first taxon is a corn field weed in Fars province and the second is rare plant from W. Azerbaijan province.

During spring 2011, some fungal isolates were recovered from sterilized soil (Fig.1, A) or vermiculite, in pots and flats in greenhouses in Shiraz University, using malt extract agar and potato dextrose agar (Fig.1, B).