Amir Ghorbankhani; Hossein Arzani; Ali Tavili; Javad Motamedi
Volume 29, Issue 1 , February 2022, , Pages 1-10
Abstract
Salsola laricina is one of the main elements of vegetation communities in the steppe rangelands of the dryland region, which protects it from disturbances and provides conditions that can preserve its ability to rehabilitate after chest, is one of the basic requirements of rangeland management in such ...
Read More
Salsola laricina is one of the main elements of vegetation communities in the steppe rangelands of the dryland region, which protects it from disturbances and provides conditions that can preserve its ability to rehabilitate after chest, is one of the basic requirements of rangeland management in such fields. Therefore, in the present study, the variability of structural and functional traits and morphological characteristics and seed germination were tested under supportive grazing. For this purpose, by establishing a sampling system inside and outside of the 10 year old Khoshkerood detention, the vegetation cover and structural and functional traits of Salsola laricina species, such as crown cover, density and forage production in the field were measured. Seed of healthy and healthy rootstocks, morphological characteristics and seed germination, such as; 1000 seed weight, germination percentage, germination rate, root length, stem, seedling, and finally vigor index (straw) Seed) was measured in laboratory conditions. The results showed that the values of structural and functional traits, inside the enclosure, are more than outside the enclosure. In this regard, the percentage of crown cover, density, and amount of production of Salsola laricina species were respectively in the enclosure relative to the outcrop, 5.46 and 3.6%, 21600 and 17000 bases per hectare and 161.4 and 12.71 kg respectively hectare. The average of morphological and germination characteristics of the seeds collected from the intruder was also greater than the outside grazing. So that the highest index of seed vigor as a sum of outcomes of morphological and germinating properties in inoculated and outcroped seeds is 389.88 and 1037.37, respectively. The increase of these values in the enclosure relative to the outcrop; indicates the effect of supportive grazing on the improvement of structural and functional characteristics and the morphological and seed germination characteristics of rangeland species in vulnerable ecosystems in arid areas.
sara Heshmati; Jamshid Ghorbani; Maryam shokri; Hasan zali
Volume 23, Issue 4 , March 2017, , Pages 772-784
Abstract
Seasonal variation in seed bank impacts vegetation dynamic. The purpose of this study was to determine the changes of soil seed bank during the growing season. This study was carried out in a summer grassland in the northern slopes of Alborz Mountain, SorkhAbad, Savadkoh in Mazandaran province, Iran. ...
Read More
Seasonal variation in seed bank impacts vegetation dynamic. The purpose of this study was to determine the changes of soil seed bank during the growing season. This study was carried out in a summer grassland in the northern slopes of Alborz Mountain, SorkhAbad, Savadkoh in Mazandaran province, Iran. Sampling was done in March, May, August and October 2010 from two soil depths (0-5 and 5-10 cm). Seed bank composition and size were determined by seed germination of soil samples in glasshouse for 11 months. In this study, 76 species were identified in the soil seed bank during the growing season. In all months, seed density was greater in the upper soil layer than that in lower soil depth. The seed bank in summer (August) and autumn (October) had the maximum seed density. Significant temporal changes were found in the seed bank of 21 species. The seed bank of Thlaspi sp. , Stellaria media, Fumaria sp., Poa bulbosa, Alyssum sp., Thlaspi hastulatum, Hieracium sp. and Myosotis silvatica significantly increased during growing season while a significant reduction was found in the seed bank of Sonchus oleraceus, Cynodon dactylon, Carex sp., Potentilla canescense, Digitaria sanguinalis, Taraxacum montanum, and Dactylis glomerata.For some species such as Medicago lupulina, Agropyron repens, Veronica persica, Stachys byzantine, Tragopogon sp., and Bromus sp. soil seed banks showed a peak and then significantly declined.
Saeedeh Sadadt Mirzadeh; Adel Jalili; soheila Ashrafi
Volume 21, Issue 3 , December 2014, , Pages 562-569
Abstract
Scarification is one of the most effective treatments in improving seed germination. The seed germination percentage of some species is increased by scarification treatment. In the current study, the seeds were collected from different regions of the country and the effects of scarification on seed germination ...
Read More
Scarification is one of the most effective treatments in improving seed germination. The seed germination percentage of some species is increased by scarification treatment. In the current study, the seeds were collected from different regions of the country and the effects of scarification on seed germination percentage and germination speed of Hedysarum formosum, Sesbania punicea, Vicia lathyroides, Ononis spinosa from Papilionaceae family, Althea wilhelminae from Malvaceae family, Bryonia aspera from Cucurbitaceae family,and Vaccaria grandiflora from Caryophyllaceae family were studied. According to the obtained results, scarification had a significant positive effect on seed germination percentage and germination speed of all species except Bryonia aspera. However, scarification treatment had no significant effect on seed germination percentage of Hedysarum formosum, but increased the speed of seed germination. Our results clearly showed that scarification could enhance the speed of germination in the species of papilionaceae family, as compared to other families.
Hosein Azarnivand; Yaser Ghasemiaryan; Reza Yari; Mohammad Ali Zare Chahouki; Esfandyar Jahantab
Volume 19, Issue 2 , September 2012, , Pages 297-305
Abstract
The aim of this study was to investigate allelopathic activity of aerial and underground organs of mountain sagebrush (Artemisia aucheri) on seed germination features, root length, shoot length and seed vigor of Festuca ovina.For this purpose, species of mountain sagebrush were collected from Taleghan ...
Read More
The aim of this study was to investigate allelopathic activity of aerial and underground organs of mountain sagebrush (Artemisia aucheri) on seed germination features, root length, shoot length and seed vigor of Festuca ovina.For this purpose, species of mountain sagebrush were collected from Taleghan rangelands in Tehran Province and then were dried in direct sunlight and grinded.Powder derived from aerial and underground organs to the amounts of 3, 6 and 9 grams were separately mixed with 900 grams of sand in completely randomized blocks with four replications. In each pot, 10 seeds were planted at a depth of 2-3 cm. Germination percentage, germination velocity, seed vigor, root length, and shoot length were measured. Data analysis was performed using MSTATC software and mean comparisons were carried out using Duncan's test. Results showed that there were no significant differences among measured factors. Also, the shoot and root lengths showed significant differences at probability levels of 5% and 1%, respectively. According to the results, Artemisia aucheri caused a reduction of root length in Festuca ovina.
Ghasemali Dianati-Tilaki; Bahman Shakarami; Masoud Tabari; Behzad Behtari
Volume 18, Issue 3 , September 2011, , Pages 452-462
Abstract
Salinity is one of the most important abiotic stresses that negatively affects the seed germination and growth of seedlings in plants. NaCl priming is of techniques to improve the seed performance and could increase germination percentage, growth of the seedlings and the mean time of seed germination ...
Read More
Salinity is one of the most important abiotic stresses that negatively affects the seed germination and growth of seedlings in plants. NaCl priming is of techniques to improve the seed performance and could increase germination percentage, growth of the seedlings and the mean time of seed germination under salinity conditions. This study was conducted to improve the seed performance of Festuca ovina under salinity stress conditions. A factorial experiment was applied based upon a completely randomized design with three replications (50 seeds per Petri dish). The effects of priming with three optimized dose (15, 30 and 45 dS/m) of NaCl solution for 24 h at 22±2 oC under dark conditions were assessed for improving seed traits of sheep fescue. NaCl primed Seeds were also examined at different salinity levels) 0, 5, 10, 15 and 20 dS/m). Germination percentage and mean germination time were significantly affected by interaction of salinity and priming. Root length, shoot length and vigor index was not affected significantly by priming treatments in all salinity levels. Germination percentage of primed seeds especially in high salinity levels (15 and 20 dS/m) was greater than to non-primed seeds. The results showed that NaCl priming (especially at 45 dS/m for 24 h) in high salinity levels could increase the seed yield of Festuca ovina in terms of seed germination.
Atta Rezaie
Volume 16, Issue 1 , December 2009, , Pages 124-136
Abstract
Using petroleum mulch to fix shifting sand dunes in Iran historically refers to 40 years ago. Investigation of the impacts of the petroleum mulch on seed germination and seedling and cutting establishment is always a big dilemma. To reduce or eliminate the negative effects of the petroleum mulch, polylatice ...
Read More
Using petroleum mulch to fix shifting sand dunes in Iran historically refers to 40 years ago. Investigation of the impacts of the petroleum mulch on seed germination and seedling and cutting establishment is always a big dilemma. To reduce or eliminate the negative effects of the petroleum mulch, polylatice polymer is introduced as a substitution. Polylatice is a natural polymer, which due to forming a polymeric network can bond solid materials together. This study was carried out to compare the effectiveness of the Polylatice polymer and petroleum mulch for sand dune stabilization and plant growth establishment. The research was conducted in two phases: greenhouse and field work. In greenhouse phase, the effect of Polylatice on seed germination and establishment of Haloxylon persicum was investigated in comparison with the petroleum mulch in a completely randomized design with four treatments and three replications (petroleum mulch, soluble Polylatice, polylatice- sand, and blank). Two dependent variables of germination “three weeks after seeding” and “seven weeks after seeding” were chosen to investigate the treatments' effects. In three weeks after seeding, the least germination percentage belonged to Polylatice-sand treatment, and the maximum belonged to petroleum mulch. Minimum and maximum germination in seven weeks after seeding was obtained on Polylatice-sand and blank treatments, respectively. In field experiment, the effectiveness of the treatments on dependent variables (establishment of Haloxylon persicum and Caligonom sp) were investigated in a completely randomized design. Data were subjected to analysis of variance (ANOVA) and means were classified using the Duncan multiple-range test. One way ANOVA showed no significant effect of treatments on establishment of seedlings and cuttings establishment