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Showing 6 results for Morphology

G. Tahmasebi, R. Ebadi, N. Tajabadi, M. Akhondi, S. Faraj,
Volume 6, Issue 2 (7-2002)
Abstract

Small honeybee (Apis florea) is one of the common species in Iran. Apis florea lives in southern Iran and plays an important role in the polination of plants in this region. In a series of studies during the years 1997-1998, the genetic populations of the Iranian small honeybee and the effects of geographic and climatic conditions on the morphological variation and separation of Iranian small honeybee were investigated. For this purpose, 400 samples of worker bees from 40 colonies from 26 cities in 9 provinces were collected and twelve morphological characters were measured, using Ruttner method (1978). To determine geographical and climatological variables, average values collected by synoptic stations and other meteorological stations of Iran Meteorological Organization were used. The principal components analysis was used in the statistical analysis of the data obtained. The results show that there exist two distinct groups of small honeybee populations in Iran. Southwest of Iran hosts a class of bigger bees forming one distinct group while southeast of Iran hosts smaller bees forming the second group. Latitude has a positive correlation with size of body, wings and legs. Amount of precipitation has a nagative correlation with size of body, wings and legs. Temperature, wind speed. relative humidity, freezing days and other parameters did not show any correlations with size of body. The results from this research proved that the more northern areas with higher altitudes and more precipitation have bigger honeybees. This finding is in accordance with the Bergman law about other animals.
M. H. Farpour, M. K. Eghbal, H. Khademi,
Volume 7, Issue 3 (10-2003)
Abstract

Gypsiferous Aridisols are of great importance and extent in arid and semi-arid environments. There is a close relationship between soil genesis and landscape positions. This study aimed to determine the genesis and classification of gypsiferous soils and to investigate the relationship between micro-and macro-morphology of gypsum crystals and geomorphic positions in Rafsanjan area. The study area is located in Nough, 30 km north of Rafsanjan with a mean annual precipitation of 60 mm. Seven representative pedons were selected on different geomorphic positions. Physico-chemical, micromorphological, XRD, and SEM observations were performed on soil samples. Rock pediment geomorphic surfaces, that are in fact peripheries of old closed water bodies in central Iran, are the source of gypsum in the area. Large gypsum pendants and microforms of lenticular, vermiform, platy, and interlocked gypsum plates are found in rock pediment. The amount of gypsum and the size of pendants decrease moving down the slope. Lenticular and interlocked gypsum plates are found in a transition of pediment and playa. Puffy ground is observed on the saline surface of playa. Lenticular and vermiform gypsum crystals increase down the slope, but alabastrine gypsum is the most dominant form of gypsum in the playa surface. Large amounts of soft gypsum nodules are found on the rock pediment surface (western slope). In addition, spindle form of gypsum and palycrete bundles are observed in this position. Wind action played a significant role in the genesis and development of soil in rock pediment. A close relationship was found between morphology of gypsum crystals and geomorphic positions.
S. Ayoubi, M. Karimian Eghbal, A. Jalalian,
Volume 10, Issue 1 (4-2006)
Abstract

Paleosols include soils formed under climatic condition different from the present. Although such soils are widespread in central Iran region, adequate investigations of them are yet to be carried out. Micromorphology is one of the most important tools in plaeoclimatological studies. This investigation was carried out to study microscopic features of two paleosols from Isfahan province to reconstruct the paleoclimatic condition during the Quaternary. The results of this study indicate that strong clay coatings are presented in Sepahanshahr paleosol, indicating moisture regime in the past. This paleosol is polygenetic due to calcite and gypsum accumulation during drier periods compared to clay illuviation condition. Micromorphological features in Segzi paleosol indicate that this area has experienced a swampy environment during the younger Dryas. The overall results from this study indicate that climatic oscillation evidences during Quaternary have been preserved in paleosols from Isfahan region.
H. Yosef-Zadeh, M. Tabari, K. Spahbodi, Gh. Jalali,
Volume 12, Issue 44 (7-2008)
Abstract

In order to predict Caucasian maple (Acer velutinum Boiss. ) seedling growth based on nursery Orimel, Eighty six one year old seedlings located at 1550 meters above sea level in Sari, north of Iran were randomly selected. Collar diameter, height, leaf area, photosynthesis area and leaf area/leaf weight ratio were determined. Then multivariate regression models between leaf characteristics and growth characteristic were drawn. The results indicated that number of leaves and photosynthesis area can estimate the height growth of a seedling. Also, mentioned characteristics of leaf can estimate the biomass of stem as a well as growth characteristics. According to the correlation between growth characteristics and leaf characteristics, it would be concluded that the photosynthesis area of leaf can be suitable for early selection of seedling for reforestation. Also, this result shows the importance of increasing the establishment and growth of maple seedlings in plantation areas.
H Askarian, B Sharifnabi, M Olia, E Mahdikhani, A Akhavan,
Volume 13, Issue 47 (4-2009)
Abstract

Root knot nematodes (Meloidogyne spp.) cause yield loss in all countries, of which, M. javanica, is the most widespread species in Iran. In order to identify M. javanica, 100 infected root and soil samples of root knot nematode were collected from different regions of Kerman province. After purification of populations and identification of M. javanica based on morphological and morphometerical characters of females and second stage juveniles (J2), total DNA was extracted from eggs, J2 and female adults. Specific 670 and 1600 bp bands were amplified in all M. javanica populations using species-specific primer pairs including OPARjav / OPAFjav and Mjavf / Mjavr These specific bands could not be amplified in other species such as M. incognita and M. arenaria. It seems that, application of these species specific primers in comparison with morphological characters would be more applicable, leading to easier identification of M. javanica.
A Razavinasab, A Tajabadi, H Shirani, H Dashti,
Volume 13, Issue 47 (4-2009)
Abstract

To study the effect of nitrogen, salinity and organic matter on growth and root morphology of pistachio (Cv. Badami), a greenhouse experiment was conducted. Treatments consisted of four nitrogen (N) levels (0, 60, 120 and 180 mg kg-1 soil as urea), four salinity levels (0, 800, 1600 and 2400 mg NaCl kg-1 soil) and three organic matter (OM) levels (0, 2 and 4% soil as farmyard manure). Treatments were arranged in a factorial manner in a completely randomized design with three replications. As the salinity levels increased, leaf, stem and root dry weights and root density, were significantly reduced. Addition of N up to 120 mg kg-1 soil, had no significant effect on growth, but the highest N level (180 mg kg-1), due to nutrient imbalance, reduced abovementioned plant parameters. In low salinity levels, N application improved the growth of pistachio seedlings, but at the highest salinity level, N addition didn’t suppress the adverse effects of soil salinity. Due to useful physical and nutritional properties of soil organic matter, addition of OM significantly increased leaf, stem and root dry weights, stem height, shoot/root ratio and root density.

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