@article{ author = {Kafi, M.}, title = {Apex Development of Three Wheat Cultivars in the Presence of Salinity}, abstract ={Intra-specific variations in apex development of two salt-tolerant cultivars (Cross Rowshan 11 (CR) and Kharchia-65) and one salt-sensitive cultivar (Ghods) of spring wheat (Triticum aestivum L.) grown in sand culture at selected levels of salinity (0, 100, 200, and 300 mol m-3 NaCl and CaCl2 in 5:1 molar ratio) were studied. To determine the apex lengths and the number of spikelet primordia in the apex, the main shoot apex was dissected. Results indicated that final spikelet number of wheat cultivars decreased with increasing salinity. Cultivars showed different responses to a particular level of salinity. Duration of spikelet development from double ridge to terminal spikelet, spikelet number and apex length declined in the presence of salinity. Both shorter duration and reduced rate of spikelet initiation were responsible for reduction in spikelet number in salt-treated plants. Cultivar CR showed a better performance during spikelet initiation period and produced relatively more spikelets under saline conditions than the others.}, Keywords = {Salinity,Wheat,Apex development,Phenological stages}, volume = {3}, Number = {1}, pages = {1-8}, publisher = {Tarbiat Modares University}, url = {http://jast.modares.ac.ir/article-23-9345-en.html}, eprint = {http://jast.modares.ac.ir/article-23-9345-en.pdf}, journal = {Journal of Agricultural Science and Technology}, issn = {1680-7073}, eissn = {2345-3737}, year = {2001} } @article{ author = {TavakkolAfshari, R. and Hucl, P.}, title = {Temporal Changes in Abscisic Acid Concentration in Dormant and Non-Dormant Seeds of Wheat (Triticum spp.) Genotypes}, abstract ={Little is known about the levels and physiological role of endogenous abscisic acid (ABA) during after-ripening and germination. Genetic variants for ABA content were investigated to account for the role of ABA in the persistence of seed dormancy. In this study, genotypic variation in ABA contents at Zadok’s Growth Stage 92 (ZGS 92), temporal changes in ABA during two physiological stages (after-ripening and water uptake), and responsiveness of wheat seed to applied ABA at different concentrations, of two tetraploid and two hexaploid wheat genotypes were examined during 1996 and 97. A combined analysis of variance indicated no significant differences in ABA among genotypes at ZGS 92. During the early stages of germination, endogenous ABA in the caryopses of the four wheat genotypes was analyzed. The results showed a transient increase in ABA content (up to 4 hours) occurring first during imbibition, followed by a decline up to 12 hours and an increase thereafter. ABA declined in all genotypes during seven weeks of after-ripening (dry storage). The four genotypes had reductions in ABA up to 4 weeks of after-ripening. An increase in ABA was observed during the fourth and fifth weeks of after- ripening with a decline after seven weeks. ABA had a little effect on germination index at the lower temperature (10 °C). Our results suggested that wheat grains are able to synthesize ABA during imbibition. However, no significant differences between dormant and non-dormant genotypes were detected. A decrease in ABA during after-ripening could have a role in loss of seed dormancy.}, Keywords = {After-ripening,Abscisic acid,Dormancy,Germination,Imbibition,Seed}, volume = {3}, Number = {1}, pages = {9-18}, publisher = {Tarbiat Modares University}, url = {http://jast.modares.ac.ir/article-23-104-en.html}, eprint = {http://jast.modares.ac.ir/article-23-104-en.pdf}, journal = {Journal of Agricultural Science and Technology}, issn = {1680-7073}, eissn = {2345-3737}, year = {2001} } @article{ author = {Pourreza, J. and Classen, H. L.}, title = {Effects of Supplemental Phytase and Xylanase on Phytate Phosphorus Degradation, Ileal Protein and Energy Digestibility of a Corn-soybean-wheat Bran Diets in Broiler Chicks}, abstract ={Effects of supplemental phytase and xylanase in a corn-soybean meal based diet containing 250 g/Kg wheat bran, were investigated. on broiler performance and phosphorus degradability and nitrogen digestibility. Phytase (500 and 1000 FTU) and xylanase (2700 and 5400 EXU) individually and in combination were added to the basal diet and given to 6 replicate groups (4 birds per replicate). At 21 days of age, birds were weighed and killed , ileal contents were collected and analyzed for P, N, chromic oxide and gross energy. Added phytase significantly (P<0.01) improved feed conversion ratio (FCR) (1.59 vs 1.62 g /g) and tibia ash (464.4 vs 444.3 g/Kg). Protein digestibility was increased (81.7 vs 79.4%) significantly (P<0.01) by 500 FTU/Kg added phytase. Supplemental xylanase significantly (P<0.01) improved FCR (1.58 vs 1.63 g/g) and protein digestibility (82.0 vs 80.4%). Phytate P degradability was significantly (P<0.02) improved by added phytase (41.4 vs 27.8%). Combination of supplemental phytase and xylanase had some beneficial effects on improving the nutritive value of diets containing wheat bran for broilers.}, Keywords = {Broiler,Phytase,Wheat bran,Xylanase}, volume = {3}, Number = {1}, pages = {19-25}, publisher = {Tarbiat Modares University}, url = {http://jast.modares.ac.ir/article-23-9188-en.html}, eprint = {http://jast.modares.ac.ir/article-23-9188-en.pdf}, journal = {Journal of Agricultural Science and Technology}, issn = {1680-7073}, eissn = {2345-3737}, year = {2001} } @article{ author = {Alavipanah, S. K. and DeDapper, M. and Goossens, R. and Massoudi, M.}, title = {The Use of TM Thermal Band for Land Cover/Land Use Mapping in Two Different Environmental Conditions of Iran}, abstract ={Many investigations have demonstrated that arid regions display ideal conditions for remote sensing applications such as, land cover/land use detection. The aim of this study was to evaluate the capability of Thematic Mapper (TM) thermal band in land cover/land use mapping in the Ardakan region of Yazd province, an area of desert with severe salinity conditions, and the Mook region in the Farse province, an area of mountains, forests, dry farming and orchards. Landsat TM imagery recorded on September and October, 1990 were used for land cover/land use classifications of Ardakan and Mook areas respectively. Maximum likelihood classifications were used by including TM thermal band (TM6) in band combinations. The results of image classifications showed that TM6 has improved the accuracy of classification in Ardakan, while no meaningful role was found in Mook region. Based on the results obtained it may be concluded that the effectiveness of TM bands for classification is highly dependant on land cover type, climatic, and geographic conditions. Based on the results obtained it was also concluded that TM6 plays a key role in separating urban and dark colour salt crust classes as in Ardakan area. In other words, in climatic and geographic conditions represented by dry surface and sparse vegetation, thermal band data may prove more useful.}, Keywords = {Desert,Classification,Land cover,Land use,Mountain,Thermal band}, volume = {3}, Number = {1}, pages = {27-36}, publisher = {Tarbiat Modares University}, url = {http://jast.modares.ac.ir/article-23-2246-en.html}, eprint = {http://jast.modares.ac.ir/article-23-2246-en.pdf}, journal = {Journal of Agricultural Science and Technology}, issn = {1680-7073}, eissn = {2345-3737}, year = {2001} } @article{ author = {Javady, T. and Arzani, K.}, title = {Pollen Morphology of Five Iranian Olive (Olea europaea L.) Cultivars}, abstract ={Pollen grains of five olive cultivars (Olea europaea L .) were examined, using Scanning Electron Microscopy (SEM) for identification purposes. Four measurments, polar axis (P), equatorial diameter (E), P/E ratio and exine patterns were made. Forty pollen grains of each cultivar were viewed before finally selecting a representative pollen grain. Polar diameter ranged between 22.76 μm for the ‘Mary’ and 28.58 μm for the ‘Shengeh’ ‘Zard’ and ‘Roghani’ cultivars exhibited incomplete closure of the meshes. ‘Zard’ and ‘Shengeh’ cultivars had thick muri but ‘Roghani’, ‘Mary’ and ‘Fishomi’ possessed thinner muri. Scanning electron analysis of pollen grain revealed that specific differences including variation in size and form of the meshes are exist among cultivars. The differences in the exine pattern may help for the identification of some cultivars.}, Keywords = {Pollen grain,Exine pattern,Olive (Olea europaea L. ),Pollen analysis,Scanning Electron Microscopy (SEM)}, volume = {3}, Number = {1}, pages = {37-42}, publisher = {Tarbiat Modares University}, url = {http://jast.modares.ac.ir/article-23-3710-en.html}, eprint = {http://jast.modares.ac.ir/article-23-3710-en.pdf}, journal = {Journal of Agricultural Science and Technology}, issn = {1680-7073}, eissn = {2345-3737}, year = {2001} } @article{ author = {Saba, J. and Moghadam, M. and Ghassemi, K. and Nishabouri, M. R.}, title = {Genetic Properties of Drought Resistance Indices}, abstract ={Inheritance of several yield-based drought resistance indices was studied by a halfdiallel method using seven winter wheat varieties. The parental lines were such chosen as to represent a broad range of drought stress resistance. The experiment was conducted in a split-plot design at the research farm, Faculty of Agriculture, Zanjan University, Iran, in 1998. Irrigated vs. rainfed regimes were considered as the main plots. The F1 hybrids and parental varieties constituted the subplots. From the grain yield data, some drought resistance indices such as geometric mean productivity (GMP), mean productivity (MP), standard superiority measure (SP), stress susceptibility index (SSI), stress tolerance index (STI), superiority measure (P), and tolerance (TOL) were calculated. Genetic components of variance and heritabilities were estimated using Gardner and Eberhart’s Method 3, Model II. Significant differences among parents and F1s were observed for all indices except for SSI and TOL. Significant general combining abilities (GCA) were obtained for GMP, MP, P, SP, STI, and TOL but not for SSI. Therefore, except for SSI, other indices could be regarded as heritable. The specific combining ability (SCA) effects were also highly significant for GMP, MP, P, SP, and STI. However, additive variances were more important than dominance ones. Narrow-sense heritability estimates were very low for SSI, low for TOL, but moderate for GMP, MP, P. SP, and STI. Thus selection based on the latter indices could be more promising than on SSI and TOL. It seems that SP and STI might be better yield-based drought resistance indices to be employed in plant breeding programs, because of their moderate narrow-sense heritabilities and the inherent ability of selecting high yielding genotypes in either stressed or non-stressed conditions.}, Keywords = {Wheat,Drought resistance,Combining ability,Diallel,Genetic properties}, volume = {3}, Number = {1}, pages = {43-49}, publisher = {Tarbiat Modares University}, url = {http://jast.modares.ac.ir/article-23-5572-en.html}, eprint = {http://jast.modares.ac.ir/article-23-5572-en.pdf}, journal = {Journal of Agricultural Science and Technology}, issn = {1680-7073}, eissn = {2345-3737}, year = {2001} } @article{ author = {Mohammadi, M. and Ghasemi, A. and Rahimian, H.}, title = {Phenotypic Characterization of Iranian Strains of Pseudomonas syringae pv. syringae van Hall, the Causal Agent of BacterialCanker Disease of Stone Fruit Trees}, abstract ={A total of twenty seven bacterial strains were isolated from cankerous tissues of apricot, nectarine, peach, plum, sour cherry and sweet cherry trees in Tehran province and identified as Pseudomonas syringae pv. syringae (Pss), the causal agent of the bacterial canker disease, on the basis of LOPAT (levan production, oxidase test, potato rot, arginine dihydrolase and tobacco hypersensitive reaction) and GATTa's (gelatin liquefaction, aesculin hydrolysis, tyrosinase activity and Na-tartrate utilization) group tests. Pss strains showed slight differences in morphology, phenotypic (biochemical and physiological) characteristics, serological properties, plasmid DNA and cellular protein profiles and antibiogram. They were divided into three distinct groups based on hippurate and formate utilization which was correlated with protein profile in SDS-PAGE (sodium dodecyl sulfatepolyacrylamide gel electrophoresis). The virulence of Pss was significantly associated with the degree of necrosis on immature sweet cherry fruits and the rate of in vitro syringomycin production.}, Keywords = {Bacterial canker disease,Pseudomonas syringae pv. Syringae,Stone fruit trees,Syringomycin}, volume = {3}, Number = {1}, pages = {51-65}, publisher = {Tarbiat Modares University}, url = {http://jast.modares.ac.ir/article-23-6870-en.html}, eprint = {http://jast.modares.ac.ir/article-23-6870-en.pdf}, journal = {Journal of Agricultural Science and Technology}, issn = {1680-7073}, eissn = {2345-3737}, year = {2001} } @article{ author = {Hajabbasi, M. A.}, title = {Tillage Effects on Soil Compactness and Wheat Root Morphology}, abstract ={Tillage systems influence soil physical, chemical and biological characteristics which in turn may alter, root characteristics, growth, and development. A three year study was conducted to investigate the effects of seven tillage systems on some soil (fine-loamy mixed, Typic Haplocambids) physical characteristics and wheat (Triticum aestivum L.) root morphology. Tillage treatments included moldboard plowing + disking (MD) as conventional tillage, chisel plowing + disk (CD), chisel plowing + rotary tilling (CR), chisel plowing (twice) + disking (2CD), plowing with a khishchi (a regional rigid cultivator) (KD), as non-inversion methods, and till planting with cultivator combined drill (TP), and no-tillage (NT) as direct drilling methods. Soil texture, bulk density (BD), organic matter (OM) and compactness (CI) were determined. At the depths 0-0.1, 0.1-0.2, 0.2-0.3 and 0.3- 0.4m, root mass density (RMD) was obtained, root length density (RLD) was determined and average root diameter (RD), surface area density (RSD), and root fineness (RF) were calculated. A randomized complete block design consisting of four blocks (replications) was used. For all treatments, the upper layer (0-0.lm) contained a higher quantity of RMD, RLD and RSD, but the reverse was observed for the lower layer (0.3-0.4m). The upper layer (0-0. lm) contained almost 46% of the total RMD (average of all treatments), while the second (0.1-0.2m) the third (0.2-0.3m) and fourth (0.3-0.4m) depths contained 23, 18.5 and 12.5% of the total RMD, respectively. The average RLD of four depths for MD, CD, CR and 2CD were significantly (P ≤ 10)higher than KD, TP and NT systems (24.9, 25.1, 24.2, and 23.8, as compared with 22.3,21.8 and 21.6km m-3 , respectively). Results of this study showed that, for the arid soils of central Iran, with weak structure and low organic matter content, as the number of tillage operations increased, root morphological characteristics improved.}, Keywords = {Wheat,Dry regions,Root morphology,Tillage}, volume = {3}, Number = {1}, pages = {67-77}, publisher = {Tarbiat Modares University}, url = {http://jast.modares.ac.ir/article-23-4803-en.html}, eprint = {http://jast.modares.ac.ir/article-23-4803-en.pdf}, journal = {Journal of Agricultural Science and Technology}, issn = {1680-7073}, eissn = {2345-3737}, year = {2001} }