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2. Age, growth and reproductive characteristics of the Turkmenian crested loach Metaschistura cristata (Nemacheilidae)
- Creator:
- Patimar, Rahman, Mortazaei Rishkhori, Khadijeh, and Sabiani, Alireza
- Type:
- article and TEXT
- Subject:
- age, growth, reproduction, Metaschistura cristata, and Iran
- Language:
- English
- Description:
- Metaschistura cristata is a small nemacheilid loach species found at a few localities only in Turkmenistan and Iran. The present study reports, for the first time, data on its biology, based on 747 specimens collected from the River Zanglanlou in north-eastern Iran. Specimens were collected at monthly intervals over two reproductive seasons from February to June 2007 and 2008. Maximum age, based on opercula readings, was 4+ years for both sexes. Specimens ranged in size from 25 to 87 mm total length and weighed from 0.09 to 4.91 g. Length-weight relationships implied positive allometric growth for both sexes and the sex ratio was 1 : 1.2 in favour of females. The Gonadosomatic indicated that peak reproduction occurred during April and May, with highest average values of 1.473 ± 0.99 for males and 12.9 ± 7.14 for females in April. Oocyte diameter ranged from 0.53 to 1.46 mm, with a mean value of 0.943 mm. Absolute and relative fecundity ranged between 114-1246 eggs and 79.47-1285.71 eggs/g, respectively. Absolute fecundity and oocyte diameter to fish size (length and weight) were directly correlated, while the relationship between relative fecundity and fish size (length and weight) showed an inverse power function.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/
3. Biology of the conifer needle scale, Nuculaspis abietis (Hemiptera: Diaspididae), in northern Iran and parasitism by Aspidiotiphagus citrinus (Hymenoptera: Aphelinidae)
- Creator:
- Rasekh, Arash, Michaud, J. P., and Varandi, Hassan Barimani
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, entomologie, Írán, Iran, Nuculaspis abietis, Diaspididae, Hemiptera, Aspidiotiphagus citrinus, Aphelinidae, Hymenoptera, Picea abies, Norway spruce, development, host range, parasitism, 2, and 59
- Language:
- English
- Description:
- The conifer needle scale, Nuculaspis abietis (Schrank) emerged as an important pest of conifers in the Kelardasht region of Mazandaran province, Iran, in the late 1990's. This pest feeds on conifer needles and twigs causing needle drop and branch desiccation. Its discovery in Kelardasht in Mazandaran Province necessitated a local quarantine of conifers in the genera Picea, Abies, and Pinus. We studied the life history and ecology of this scale on Norway spruce, Picea abies, under laboratory and natural field conditions. The complete life cycle of females required 206.4 ± 5.7 days in the laboratory (25 ± 1°C, 65-75% RH, 14L : 10D) and 315.7 ± 9.3 days under field conditions. In Kelardasht, numbers of adult males and females peaked in mid-June and early May, respectively, and numbers of first and second instar nymphs in mid-July and early September. Lifetime fecundity was estimated to be 57.3 ± 5.1 eggs and 54.0 ± 4.4 nymphs per female under laboratory conditions. The sex ratio ranged from 59% female for second instar nymphs to 71% female for adults. Aspidiotiphagus citrinus (Crawford) (Hymenoptera: Aphelinidae) was found naturally parasitizing the scale and overwintering in the larval stage on second instar nymphs. First generation adult wasps emerged in spring from overwintered second instar nymphs to parasitize 64.75% of first instar scales. Second generation wasps emerged from early September to mid-October and parasitized 19.75% of second instar scales, for a cumulative parasitism rate of 84.5%. and Arash RASEKH, J.P. MICHAUD, Hassan BARIMANI VARANDI.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
4. Constraining of strain ellipsoid shape from sectional data in the au bearing shear zone west of Iran
- Creator:
- Behyari , Mahdi and Kanabi , Afshin
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Ductile shear zone, strain ellipsoid, Orogenic gold, Flinn diagram, Zagros, and Iran
- Language:
- English
- Description:
- Ductile shear zone recorded valuable data about the progressive deformation and geodynamic setting of the earth crust. Analysis of the strain ratio on the deformed quartz grains in the samples of the Zagros orogenic shear zone indicated generally most of the strain ellipsoids shape are prolate and developed under constructional strain regime. Principal axes of the strain ellipticity ratio varied in the range between 2.04 to 3.12, shear strain magnitude analysis indicated εs are between “0.6 to 1.3”. Strain ellipsoid shape also revealed the propagation of the shear zone could not be coeval with the continental collision because in the collision region expected the ellipsoid shape to be oblate. Flattening strain regime in the Zagros Orogeny contemporaneous with the collisional event (D1 phase) and widespread in the Sanandaj-Sirjan Metamorphic Zone. Constructional conditions and prolate strain ellipsoid could be related to the post-collisional deformation phase (D2 phase). In this event stretching and shearing localized in the ductile shear zone and transtension structures superimposed on the former transpression structures. The deformation followed by third phase and brittle event (D3 phase) and caused to the propagation of veins. These veins somewhere cut the foliation and in the other place are parallel to foliation plane.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
5. Distribution and diversity of wheat aphid parasitoids (Hymenoptera: Braconidae: Aphidiinae) in Iran
- Creator:
- Rakhshani, Ehsan, Tomanović, Željko , Starý, Petr, Talebi, Ali-Asghar , Kavallieratos, Nickolas G. , Zamani, Abbas-Ali, and Stamenković, Srdjan
- Type:
- article, model:article, and TEXT
- Subject:
- Cereal aphids, parasitoids, Aphidiinae, Braconidae, Iran, and biodiversity
- Language:
- English
- Description:
- Eleven species of parasitoids were found to attack 7 species of wheat aphids in Iran. The Simpson's Index of diversity (D) used to compare the aphidiine diversity in various cereal crop systems in geographically different regions of Iran ranged from 0.197 to 0.488, depending on locality. There were significant differences among species diversities at different altitudes. The central highlands (1000-1500 meters above mean sea level) were the areas with the most diverse aphid parasitoid complex, differing significantly from that at lower and higher altitudes. We found that altitude explained about 10% of the cereal aphid parasitoid distribution pattern in Iran. Species of the genus Aphidius Nees were the most abundant and widely distributed. These were Aphidius rhopalosiphi De Stefani, Aphidius uzbekistanicus Luzhetski, Aphidius colemani Viereck and Aphidius matricariae Haliday. A. uzbekistanicus, Ephedrus plagiator (Nees) and Ephedrus persicae Froggat were encountered mainly on the plains at lower altitudes. Diuraphis noxia (Kurdjumov) was mainly recorded at higher altitudes in Iran along with its dominant parasitoid species, Diaeretiella rapae (MIntosh). The fact that Iran is close to the presumed area of D. noxia origin (Central Asian submountains) could be very important in further biological control efforts against this pest aphid. According to our results, Aphidius ervi Haliday is a very rare parasitoid of cereal aphids in Iran, which contrast with its high abundance in Europe and North America.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
6. Effect of temperature on some biological parameters of an Iranian population of the Rose Aphid, Macrosiphum rosae (Hemiptera: Aphididae)
- Creator:
- Mehrparvar, Mohsen and Hatami, Bijan
- Type:
- article, model:article, and TEXT
- Subject:
- Aphididae, Macrosiphum rosae, rose aphid, geographic population, Iran, development, survival, fecundity, biology, developmental threshold, and degree-day
- Language:
- English
- Description:
- The rose aphid, Macrosiphum rosae, living on rose var. Black Magic, was reared in the laboratory at four constant temperatures 15, 18, 22 and 25 ± 1°C, 75 ± 5% R.H. and 14L : 10D. Parameters investigated included developmental rate, survival, pre-reproductive delay and fecundity. The rate of nymphal development (0.17) was greatest at 22°C. The longest developmental time (12.33 days) was recorded at 15°C. The generation time was longest and shortest at 15°C and 22°C respectively. The lower developmental threshold was calculated to be 9.05°C. Based on this, the degree-day requirement from birth to adulthood was found to be 77.5 dd. The pre-reproductive delay also decreased markedly with increase in temperature from 15°C to 22°C. The longest lifespan of apterous females (12.38 d) was observed at 15°C, whereas the shortest (8.06 d) was at 25°C. The mean adult longevity declined with increase in temperature from 15°C to 25°C. The fecundity of females (progeny/female) increased from 11.38 to 28.88 with increase in temperature from 15°C to 22°C but then decreased to 8.38 as the temperature increased from 22°C to 25°C. The largest (0.311) and smallest (0.113) rm occurred at 22°C and 15°C respectively. All of the parameters of the M. rosae life cycle at the four temperatures tested were optimum at 22°C. This Iranian population of M. rosae can develop at lower temperatures than an Australian population.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
7. Effects of sodium chloride stress on gas exchange, chlorophyll content and nutrient concentrations of nine citrus rootstocks
- Creator:
- Khoshbakht, D., Ramin, A. A., and Baninasab, B.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fotosyntéza, photosynthesis, Írán, Iran, growth analysis, mineral nutrition, net photosynthetic rate, salinity, 2, and 581
- Language:
- Multiple languages
- Description:
- a1_We investigated the influence of salinity (0, 25, 50, or 75 mM NaCl) on gas exchange and physiological characteristics of nine citrus rootstocks (Cleopatra mandarin, Carrizo citrange, Macrophylla, Iranian mandarin Bakraii, Rangpur lime, Rough lemon, Sour orange, Swingle citrumelo, and Trifoliate orange) in a greenhouse experiment. Total plant dry mass, total chlorophyll (Chl) content, and gas-exchange variables, such as net photosynthetic rate (PN), stomatal conductance (g s), intercellular CO2 concentration, were negatively affected by salinity. In addition, ion concentrations of Cl- and Na+ increased by salinity treatments. Salinity also increased Mg2+ content in roots and reduced Ca2+ and Mg2+ concentrations in leaves. The K+ concentration in leaves was enhanced at low salinity (25 mM NaCl), whereas it decreased with increasing salinity stress. Salinity caused a decline in K+ contents in roots., a2_The rootstocks showed major differences in the extent of Cl- and Na+ accumulation in leaves and in their ability to maintain the internal concentrations of essential nutrients in response to different salinity. Therefore, in addition to inhibitory effects of high concentrations of Cl- and Na+, an imbalance of essential nutrients may also contribute to the reduction in gas exchange under saline conditions. Higher tolerance of rootstocks to salinity could be associated with the reduction of Cl- and Na+ uptake and transport to leaves, ability to keep higher Chl, gs, PN, and better maintenance of nutrient uptake even under high salinity. We found that Sour orange and Cleopatra mandarin were the rootstocks most tolerant to salinity of all nine studied. In addition, Trifoliate orange, Carrizo citrange, and Swingle citrumelo were the rootstocks most sensitive to salt stress followed by the Rough lemon and Macrophylla that showed a low-to-moderate tolerance, and Rangpur lime and Bakraii, with a moderate-to-high tolerance to high salinity., D. Khoshbakht, A.A. Ramin, B. Baninasab., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
8. Evaluation of anti-leishmanial effects of killed Leishmania vaccine with BCG adjuvant in BALB/c mice infected with Leishmania major MRHO/IR/75/ER
- Creator:
- Nahrevanian, Hossein, Jafary, Seyedeh Parisa, Nemati, Sara, Farahmand, Mahin, and Omidinia, Eskandar
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- vaccine, KLV, adjuvant, Leishmania major, immunization, and Iran
- Language:
- English
- Description:
- There are many strategies to control leishmaniasis, but majority of them are inadequate. Killed Leishmania vaccine (KLV) has been applied for its immunogenicity in human and mouse model. Bacillus Calmette-Guerin (BCG) as adjuvant is an immunemodulator inducing humoral and cellular immune responses during zoonotic cutaneous leishmaniasis (ZCL). Both KLV and BCG have been applied for their immune responses in hosts for controlling leishmaniasis. In this study, KLV and BCG were applied to inhibit replication and visceralization of Leishmania major in BALB/c mice. Mice were injected with KLV and BCG, followed by infection with promastigotes of L. major. Six weeks after infection, a small nodule appeared, which was followed by development of a large lesion and visceralization. Effects of KLV and BCG, physiopathological changes, lesion size, delay of lesion formation, proliferation of amastigotes inside macrophages and detection of amastigotes in target organs were studied. Results showed that the KLV had anti-leishmanial activity by reducing lesion size on late infection. In KLV and BCG group, the average number of amastigotes in macrophages was lower than in other groups. Significant reductions in number of amastigotes in both spleen and lymph node were observed, indicating lower visceralization of Leishmania parasites in these target organs. No significant changes were presented in body weights, survival rates and degrees of splenomegaly in test group. It can be concluded that application of KLV and BCG had acceptable efficacy in reduction of skin lesions size and proliferation of parasites, even though a few side-effects were observed. It is indicated that KLV/BSG may have ability to modulate host immune responses against Leishmania parasites and to reduce pathophysiology of the disease during infection.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
9. Finite element modeling of tectonic stress field of Iran Based on geodetic and seismic data
- Creator:
- Zamani, Behzad G.
- Type:
- article, model:article, and TEXT
- Subject:
- Tectonic stress field, Modeling, Finite element, and Iran
- Language:
- English
- Description:
- In this paper, the tectonic stress field of Iran studied by a two-dimensional elastic finite element model (FEM) using inverse modeling technique. Using the named method, the relative magnitude of the tectonic forces and the regional parameters of the major blocks estimated. Geodetic and stress analysis results used for evaluating and validating the results of the developed inverse model. This developed model allows estimating the effect of different parameters of the stress pattern. The results denote that the direction of convergence plays an important role in distribution of the stress pattern, and the shape of the plate boundary is the main factor in controlling the shape of the distribution of the maximum compressional stress. The results also show that the magnitude of the maximum principal stress axes (δ1) reduce from the west and southwest to the north and northeast of Iran. The maximum stress magnitude is dominantly in the NW-Zagros, Azarbaijan, Qatar- Kazeron, Kope-Dagh, Zabol block and Lut block, while western part of Iran shows a thrusting mode stress state.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
10. Four new Dactylogyrus species (Monogenea: Dactylogyridae) from Iranian fishes
- Creator:
- Jalali, B., Papp, M., and Molnár, K.
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- Dactylogyrus, Monogenea, freshwater fishes, Iran, and zoogeography
- Language:
- English
- Description:
- Four new Dactylogyrus species (Dactylogyrus pallicirrus sp. n. from Cyprinion macrostomum and Cyprinion watsoni, D. rohdeianus sp. n. and D. capoetae sp. n. from Capotta damascina, and D. schizocypris sp. n. from Schizocypris hrucei) are described from endemic Iranian freshwater fishes. Comments on the monogenean fauna of Iranian freshwater fishes are presented.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
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