Fatemeh Aliyari, Mehrdad Zarafshar, Ali Soltani,
Volume 1, Issue 2 (3-2015)
Abstract
Accessing to the data that could increase our knowledge associated with the response of seed to moisture content and temperature, is very important on exact time of planting decisions making. In this study Hydro-thermal-time modeling of Platycladus orientalis germination, one of the most planted trees in Iran forests, by applying 5 levels of water stress (0.-0.5, -1, -1.5, -2 MPa) and temperature treatments (10, 15, 20, 25, 30 ° C) was performed. The results showed that the optimum temperature (To) for germination is 23.12° C and basic temperature (Tb) for germination is 8.18 ° C. Meanwhile amount of the hydrotime constant (θH) for this species is 0.45. The outcomes indicated that the reduction in water potential and temperature germination is linearly reduced. Interaction of temperature and water potential factors affected significantly on time and percent germination value. A Hydro-thermal-time model was introduced for Platycladus orientalis L. in which its constant value was 105.1 MPa°C.d.
Mehdi Heydari, Ali Mahdavi, Elham Jaferyan, Vahid Mirzaeizadeh,
Volume 2, Issue 2 (3-2016)
Abstract
Judas tree belongs to valuable species in Zagros forests. Nowadays, due to the special beauty of this species, it has received substantial attention in afforestation. In this regard, the improvement of seed germination is a suitable way to improve the quantity and quality of producing seedlings in nurseries and the establishment of forest plantation. In this study, the seed germination characteristics and seedling survival of Cercis griffithii in different soil treatments have been surveyed in the nursery of Aivan County in Ilam province. The experiment was set up as a randomized complete design with four treatments each contained 120 pots. Three seeds in plastic pots were sown in nursery soil (Control Control soil- cattle manure (5:1), Control soil- Litter (5:1) and Control soil- Cattle manure- Litter (5:1:1). According to the one-way ANOVA results, significant differences were observed between soil treatments in terms of germination rate, maximum, mean daily germination and germination energy, while there were no significant differences in other germination characteristics between soil treatments. The highest germination rate, maximum, mean daily germination and germination energy were observed in the treatment of Control soil- Cattle manure- Litter. In terms of time, seedling survival decreased from September to March. The results showed that there is a significant correlation between mean daily germination and different soil composition. In general, it can be concluded that germination and survival of Cercis griffithii can be improved using organic compounds in the nursery.
Anahita Rashtian, Afagh Tabandeh Saravi, Somaya Naseh Dehabanda,
Volume 3, Issue 1 (9-2016)
Abstract
Salinity is one of environmental stresses in the world and especially in arid lands and desert that reduces production of plants and it is important to choose salt-resistant plants in all life stages, especially germination. The aim of this study was to investigate the effect of seed source (provenance (on germination and morphological traits of Amygdalus elaegnifolia saplings undersalt stress. The experiment was carried out as factorial in completely randomized design withthree replicates. Seed source (FereydonShahr, Kazeron and Semirom) and salinity treatment withfour levels (0, 1.5, 3 and 5 dSm-1) using NaCl were considered as first and second factors, respectively. The measured variables were germination percentage, germination rate, vigor index, shoot length, radicle length, shoot wet weight, radicle wet weight, shoot dry weight, radicle dry weight, total leaf number, and radicle length/shoot length. The results of analysis of variance and mean comparison showed that salinity made significant differences in most of the investigated traits of Amygdalus elaegnifolia. In the control treatment of salinity, significant differences were found among the studied seed sources but the effect of seed sources was not significant in the other levels of salinity. In general, Fereydunshahr was the best of all studied provenances in non-saline conditions (control treatment).
Mr Mohammad Fooladvand, Dr Vahid Etemad, Dr Mohsen Javanmiri Pour, Dr Mohammadali Zarechahoki, Mr Mostafa Khoshnevis,
Volume 4, Issue 1 (12-2024)
Abstract
Background and purpose: The Sumac shrub is a commonly used species for afforestation in arid and semi-arid areas to reclaim land. Additionally, the fruits of Sumac are used to support the economy of local communities. The purpose of this study is to analyze the type of dormancy exhibited by Sumac seeds, and to determine the effects of different dormancy breaking treatments. These treatments include scratching the seeds, treating them with boiling water, sulfuric acid, cold layer, and gibberellic acid (GA3) to increase the rate of germination.
Materials and methods: A study was conducted at the Forest Tree Seed Technology Laboratory of the Department of Forestry, Faculty of Natural Resources, University of Tehran. The study was conducted in four replicates of 50 seeds using a completely randomized design. The first step was to measure the survival percentage of the seeds using the tetrazolium test, which was found to be 85.5%. The study involved different treatments applied on sumac seeds. The treatments without the presence of gibberellic hormone included: A) Boiling water treatment with three cold layer durations of 2, 4 and 6 months, B) Chemical scraping treatment with 96% sulfuric acid at three levels of 40, 80 and 120 minutes and three cold layer durations of 2, 4 and 6 months, C) Chemical scraping treatment with 96% sulfuric acid in three levels of 40, 80 and 120 minutes and boiling water treatment and three durations of the cold layer of 2, 4 and 6 months. The treatments with the presence of gibberellic acid hormone included: A) Treatment with boiling water and cold layer in three periods of 2, 4 and 6 months and gibberellic acid at three levels of 250, 500 and 1000 P.P.M, B) Treatments with sulfuric acid for 80 minutes and cold layer in three periods of 2, 4 and 6 months and gibberellic acid in three amounts of 250, 500 and 1000 P.P.M, C) Treatments with sulfuric acid for 80 minutes, boiling water and cold layer in three periods of 2, 4 and 6 months and gibberellic acid in three amounts of 250, 500 and 1000 P.P.M.
Findings: The analysis of variance for germination speed confirms that there is a significant variation in the average germination rates between different treatments. The average germination rates for the sulfuric acid treatment, which involved boiling cold water for 120 minutes over a period of two months, was 7.96. This treatment showed a significant difference in growth compared to the control treatment, which had an average growth rate of 96.7. Similarly, the 2-month cold broth treatment had an average germination rate of 7.61, which was significantly different from the control treatment. The Gibberellic acid 500 ppm cold decoction treatment for 6 months resulted in a significant growth rate of 18.75, which was significantly different from the control treatment. Finally, the Gibberellic acid 250 ppm + boiling water + cold treatment for 6 months had an average germination rate of 15.79 and showed a significant difference in growth compared to the control treatment.
Conclusion: According to the results, sumac seeds exhibit both physical and physiological dormancy. The treatment of scraping with sulfuric acid followed by a cold layer did not have a significant impact on dormancy breaking and germination. However, the use of gibberellic acid improved both the percentage and speed of germination, with the best results obtained using a treatment of 500 ppm gibberellic acid along with boiling water and cold storage for six months, resulting in a germination rate of 18.79%.
