Bayzid Yousefi; Sedigheh Zarekia
Volume 29, Issue 4 , January 2023, , Pages 562-578
Abstract
To evaluate the genetic diversity and relationships among traits of herbaceous milkvetch, 10 genotypes belong to five species including Astragalus vegetus. A. brevidens, A. brachyodontus, A. effusus and A. cyclophyllus in Sanandaj in a randomized complete block design with three replications were studied. ...
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To evaluate the genetic diversity and relationships among traits of herbaceous milkvetch, 10 genotypes belong to five species including Astragalus vegetus. A. brevidens, A. brachyodontus, A. effusus and A. cyclophyllus in Sanandaj in a randomized complete block design with three replications were studied. Seed sowing was done in November 2018 and morphological traits of plant in spring 2020 were measured. Analysis of variance released significnant (p≤0.01 and 0.05) difference for milkvetch populations (G) for all studied traits. In 2020 (two years old plants), the mean of plant establishment was about 26%, the number of primary branches was 3.2, plant height, the tallest stem length and crown diameter were 16.9, 19.2 and 15.4 cm respectively, the length and width of the root were 17.4 and 6.2 cm, respectively, the average of fresh weights of the whole plant, arial and root parts were 2.3, 1.9 and 0.4 g and the average of dry weights of the whole plant, arial and root parts were were 0.9, 0.7 and 0.2 g respectively, average dry to fresh weight ratio was 0.38. Average of leaflet per leaf was 7.7, so mean of length and width of leaf and leaflet were 7.5, 3.7, 2.3 and 0.5 cm respectively. Up to this stage, the accession of A. effusus Darreh Shohada (West Azerbaijan) and three accession of A. vegetus (Zereshk of Qazvin, Saral of Kurdistan and Qarehbagh of West Azerbaijan) were superior ones in terms of forage production and other studied traits. The weight of the plant was positively correlated with plant vigor, length and width of leaf (p≤0.05) and with plant height, crown diameter, number of primary branches, length and width of root, arial and root weight at 1% probality level. The results of stepwise regression of forage yield on other traits showed that plant weight, establishment percentage, plant height and crown diameter at 1% and the length of leaf and root at 5% probality level (R2adj = 91.1%) were forage yield components. Therefore, in order to achieve higher forage, the genotypes with larger aerial parts and deeper roots should be selected.
Mohsen Sherafatmandrad; Gholamali Heshmati; Mohammadrahim Forouzeh; Hosein Badripour
Volume 21, Issue 3 , December 2014, , Pages 447-454
Abstract
Measurements of production and utilization of key range plant species are of utmost important tools for making range management decisions specially for stocking rate determination. A study was conducted to examine the relationships of production and utilization of Agropyron cristatum and Stipa barbata, ...
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Measurements of production and utilization of key range plant species are of utmost important tools for making range management decisions specially for stocking rate determination. A study was conducted to examine the relationships of production and utilization of Agropyron cristatum and Stipa barbata, as key grasses in Chaharbagh region of Golestan province, with some dimensional parameters. For this purpose, plants height, basal diameter and canopy diameter and their dry weights were measured. Primarily, correlation matrices and Pearson correlation coefficient were used to assess the relationships of these three dimensional variables with production. The three variables were then evaluated for predicting production by using best subset and stepwise regression approaches. Utilization was assessed based on percentage of height removed in relation to percentage weight removed. Results showed that basal and canopy diameters could usefully predict the production of the two grasses. Finally, because of subjectivity of canopy diameter measurements and its weak role in explaining production variations, just basal diameter was considered in models, having linear relationship with production and the coefficient of determinations were calculated to be 72.4 and 71 for A. cristatum and S. barbata, respectively. Therefore, dimension analysis is an appropriate approach to estimate the production and utilization of range key grasses.
Rasool khatibi; Yaser Ghasemi Arian; Esfandyar Jahantab; Mohammad Haji hashemi
Volume 19, Issue 1 , June 2012, , Pages 72-81
Abstract
Soil properties are of the effective factors in distribution of vegetation, especially in arid and semi arid regions as the effect of geology, topography and climatic factors appeare in soil properties. In this study, soil properties of rangeland vegetative types was studied in Dejinak-e-Khash in the ...
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Soil properties are of the effective factors in distribution of vegetation, especially in arid and semi arid regions as the effect of geology, topography and climatic factors appeare in soil properties. In this study, soil properties of rangeland vegetative types was studied in Dejinak-e-Khash in the southern of Taftan. Soil and vegetation sampling were done in key areas of each site by random- systematic method. Plot size was determined with minimal area method. Also, the size and number of transects for sampling were determined according to species and vegetation changes. Physicochemical properties of soil including soil texture, pH, electrical conductivity, lime and organic matter were measured. After measuring soil and plant factors, statistical analysis was performed on plant species, vegetation types and soil factors by SPSS software. Finally, the best equation and correlations were determined between vegetation types and soil parameters. Results showed that the percentage of organic matter, clay and absorbable potassium were the most important factors in distribution of key range species in the study area. In general, the results showed a significant relationship at 95% probability level for Artemisia siberi with potassium and clay, for Salsola nitraria with soil pH, and for Acanthophyllum microcephalum with total nitrogen. Also, the distribution of Hammada salicornia was significantly affected by all factors except P and EC at 95% probability level.
Mitra Shirazi; Gholam reza Zehtabian; Hamid reza Matinfar
Volume 17, Issue 2 , September 2010, , Pages 256-275
Abstract
Recently there is a great deal of interest in the quantitative characterization of temporal and spatial vegetation patterns with remotely sensed data for the study of earth system science. One of important methods for extracting information from satellites image is use of indices. In this study for enhancement ...
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Recently there is a great deal of interest in the quantitative characterization of temporal and spatial vegetation patterns with remotely sensed data for the study of earth system science. One of important methods for extracting information from satellites image is use of indices. In this study for enhancement of land cover in region of northwest Tehran near Hashtgerd some indices such as BI, MIRV2, GREENNESS, TVI, VNIR, MND، NIR, OSAVI, RA, NDVI, IR1, MSI IPV ,MSAVI, SAVI, TSAVI, PD322 ,BI, INT1, INT2, PVI, SI1, SI2, SI3, GEMI, WDVI Are used. Most of study area covers by density of vegetation (such as irrigation farming and vegetation cover around streams) and bare lands. The results have shown that TSAVI, DVI, IPVI, RA, NIR, IR1 Indices have the most effective efficiency for vegetation enhancement and SI2, BI, TVI, PVI, INT1, SI3, SI2 indices have the most effective efficiency for salinity surface. This study addressed that all of vegetation indices except DVI have correlation more than 0.8 and DVI has correlation around 0.4 with others. Meanwhile all of salinity indices have more than 0.9 correlations with each other. As conclusion, this study has shown that IRS satellites image have high accuracy for providing land cover map by use of vegetation indices, also use of salinity indices having high capability for salinity surface can be used for providing salinity maps, meanwhile vegetation indices with high correlation can be used instead each other for providing vegetation maps.
Aliakbar Emani; Aliashraf Jafari; Rajab Chokan; Ali Asgari; Farokh Darvish
Volume 15, Issue 4 , January 2009, , Pages 493-507
Abstract
In order to determine the best populations for both yield and quality traits, 36 populations of tall fescue (Festuca arundinacea) were evaluated using a triple lattice design in Ardabil, Iran during 2005-2006. The data were collected for heading date, plant height, dry matter yield and five quality ...
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In order to determine the best populations for both yield and quality traits, 36 populations of tall fescue (Festuca arundinacea) were evaluated using a triple lattice design in Ardabil, Iran during 2005-2006. The data were collected for heading date, plant height, dry matter yield and five quality traits dry Matter digestibility (DMD), water soluble carbohydrates (WSC), crude protein (CP), acid detergent fiber (ADF) and total ash over two years. Near infrared spectroscopy was used for estimation of the quality traits. Result showed significant difference among populations for all of traits except the ash, in the first year. The populations VIII (Russia), 782026 (Shahrekord) and 60075 (Tavankesh) with average values 5.76, 5.32 and 5.5 ton/ha had the highest total dry matter production, respectively. They were suggested as the promising populations for produce synthetic varieties. The populations of 60075 (Tavankesh), 60066 (Borojen), had higher and lower values for plant heights, respectively. For heading date, 418 (Australia) and 1317 (Iranian Gene bank), were recognized as latest and earliest populstions, respectively. The populations of 60071 (Borojen) and 078 (USA) had the higher values for DMD. Results of correlation analysis showed that DMD was positively correlated with WSC, while the correlation among ADF with both DMD and WSC was negative. Heading date was negatively correlated with both DM yield and plant height. The relationships among DM yield with both DMD and WSC were weak and non significant. It was concluded that the population VIII (Russia), 782026 ( Shahre kord) and 60075 (Tavankesh) with higher forage production and 60071 (Borojen) and 078 (USA) with higher quality were suggested as the best populations for cultivation in semi steppe area of northwest of Iran.