Rostaniha
Year:2005 | Volume:6 | Issue:1 |Papers Count:7

The genus Cyperus belongs to tribe Cypereae, subfamily Cyperoideae and family Cyperaceae that is the largest genus in this family after Carex. The classification of genus Cyperus is still unsettled because of morphological variations and therefore, makes determination of subgenera boundaries and species difficult. In Flora Iranica (KUKKONEN 1998) this genus was divided to six subgenera. In this research, taxonomic revision of subgenus Cyperus in Iran were studied. Out of 300 herbarium specimens (IRAN, TARI etc. Herbaria) and newly collected plants from different parts of the country, 10 species belonging to eight sections are identified. The results showed that, based on inflorescence type, this subgenus may be divided to three groups as follow: group 1 (C. bulbosus), group 2 (C. imbricatus, C. dives, C. glomeratus) and group 3 (C. longus, C. rotundus, C. serotinus, C. glaber, C. esculentus and C. malaccensis).Morphological characters and determination key of the Iranian species new to Iran as well as geographical distribution in the world and Iran for each species are also presented.

During 2003-04 major mushroom production units of Tehran province were sampled and 103 fungicolous isolates were obtained (Table 1). Verticillium fungicola (with 50 isolates), Trichoderma harzianum (with 24 isolates), Cladobotryum dendroides (with 16 isolates) and Acremonium crotocinigenum (with 11 isolates) were the most frequent fungi associated with the cultivated mushroom, Agaricus bisporus. The report of A. crotocinigenum and two varieties of V.fungicola (jungicola and flavidum) is new to the mycoflora of Iran. The validity of temperature tests for distinction between T. harzianum and T. aggressivum is under question as the Iranian isolates of T. harzianum have the same growth rate as those of T. aggressivum, but based on molecular data (AFLP) they are different from both species. They could however represent a new taxon. Verticillium fungicola causes dry bubble disease and also distortion and mummification of the fruit-bodies of Agaricus bisporus (Fig. 1). The two varieties are indistinguishable from each other on morphological grourids (Fig. 3), but they are distinct at ITS level (Fig. 2).

Based on the morphological study of specimens of rust fungi collected during 2002-2003, a contribution is made to the rust fungus flora of Hamedan province: Uromyces inaequialtus var. ecbatanensis is described as new taxon. Melampsora allii-fragilis and Uromyces acantholimonis var. zagrosica are new reports for Iran. New observations on already known species were made: the aecia of Melampsora epitea var. epitea on Dactylorhiza umbrosa and Phragmidium sanguisorbae subsp. mediteraneum on Sanguisorba minor are newly recorded from Iran. Muscari neglectum for Aecidium muscari, Salix aegyptiaca for Melampsora epitea, Euphorbia seguieriana for Melampsora euphorbiae, Acantholimon latifolium for Uromyces acantholimonis var. zagrosica and Euphorbia macroclada for Uromyces tinctoriicola are reported as new hosts at least in Iran.

This paper presents the findings of a research on the genus lsatis L. (Brassicaceae) in Iran. lsatis specimens kept in major herbaria of Iran were examined carefully. Fresh specimens were collected from Tehran, Mazandaran, Semnan, Hamedan, Kurdistan, W. Azarbaijan , E. Azarbaijan, Ardebil and Ghazvin provinces. Images of type or otherwise valid specimens kept in Viena, Munich, Montpollier and Kew herbaria were obtained and considered in the research.The relationships between the species were also studied using numeric taxonomy method. The species of the genus Pachypterygium found in Iran were included in the numeric taxonomy beside the genus lsatis L. Hierarchical clustering analysis was carried out based on 69 characteristics. Dendrograms and plots were drawn.One new subspecies of I. cappadocica was also reported to the world: Isatis cappadocica Desv. subsp. kurdica Sajedi & Sharifnia, subsp. Nov.Differt a cetro subspeciebus fructibus majoribus usque ad 23 mm longis et 35 mm latis, ±reniform is, truncatis.Typus: Iran, Kurdistan, Bijar, Kuh-e Hamzeharab, 2000-2500 m, Sajedi, Aghabeigi & Eskandari (holotypus IRAN 39I 10).Other findings of the research are summarized as follows:Two species, namely, I. ornithorhynehus and I. speetabilis and one subspecies, I. tinetoria subsp. tomentella, were reported to the flora of Iran.The occurence of I. tinetoria in Iran was clarified and documented.Three species of the genus Pachypterygium, namely, P. brevipes, P. multieaule and P. stoeksii, together with I. traehyearpa from the section Isatis were transferred to the section Eremoglaston of the genus Isatis L.A new key was developed to the genus Isatis and the subspecies of I. cappadociea.Geographical distribution maps of all the species were prepared. As a result of the present study, the number of members of the genus Isatis L. reached to 22 species.

The interactive effects of nickel (Ni) and ascorbic acid (AsA) and gibberellin (GA3) on soybean seedlings (Glycine max L. cv. Union x Elt) were examined. Seven-day old hydroponically-grown seedlings were exposed to NiCl2, 6H2O (0.5 mM), either with or without AsA (1 mM) or GA3 (0.05 mM) or AsA (1 mM) plus GA3(0.05 mM), for five days. Nickel toxicity symptoms, such as formation of reddish-brown mottled spots on the leaf blade, observed in Ni-treated plants. Addition of GA3 or AsA to the culture medium reduced toxic effects of nickel. Interestingly, with application of GA3 plus AsA, these symptoms did not appear in Ni-stressed plants. Ni decreased dry weights of both roots and shoots and reduced chlorophyll content in leaves. An enhanced level of malondialdehyde and changes in the activities of the antioxidant enzymes, catalase (CAT, EC 1.11.1.6) and guaiacol peroxidase (GPX, EC 1.11.1.7), in both roots-and leaves indicated that Ni caused oxidative stress in soybean plants. The Ni-stressed seedlings that exposed to AsA or GA3, especially both GA3 plus AsA, exhibited much better growth, when compared to those Ni-treated plants. Interaction of AsA plus GA3 prevented the decrease in chlorophyll content and lipid peroxidation as well as increased the activities of CAT and GPX enzymes. These results suggest that GA3 plus AsA treatment causes a decrease in the negative effects of heavy metal damage in soybean seedlings.

During 2001-2002, a total number of 164 soil-root samples were collected from citrus orchards of six provinces, namely, Fars, Gilan, Mazandaran, Kerman, Hormozgan and Sistan va Baloochestan. Soil samples were decanted and centrifuged and spores were collected and examined. Out of 23 identified species, five species were recognized new to Iran mycoflora. New species are as follows: Gomus albidum, G. diaphanum, G. invermaium, G. tortusum and Scutellospora erythropa.