مجله اکوفیزیولوژی بذر
پیاپی 2 (پاییز و زمستان 1394)

Nettle with scientific name Urtica dioica L. plant of the family nettle, herbaceous perennial a height of one to two meters, and have high allopathic effect. Many chemicals have allopathic characteristics, have more impact on seeds germination than other stages of development and establishment. Wheat (Triticum aestivum L.) grows in most weather conditions and in a wide range, and sensitive to allelopathic materials.This study aimed to evaluate the effect of nettle extract on seed germination components and seedling growth of two wheat cultivars. Check nettle plant allelopathic potential on the germination characteristics and early growth of wheat were the goals of this research.

A factorial experiment in a completely randomized design with four replications was conducted in the laboratory of the researcher's seed technology University of Shahed in 2014. Experimental factors were two wheat cultivars (Sardary and Azare 2) and three levels of allopathic substance concentration (0, 15 and 30%) (15% = 15 ml aqueous extract in 100 ml of water and 30% = 30 ml aqueous extract in 100 ml of water). For nettle extracts preparation, 20 grams of powdered whole plant collected from the South East of Tehran (Varamin and Pakdasht) was added into the dish containing 200 ml of distilled water for 24 hours on shaker with 110 laps in minutes, and after centrifugation solution to the soluble extracts were prepared. Twenty-five wheat seeds disinfected then replaced in two layers of filter paper (to keep better extract). The petridishes transferred to a germinator with 25 degree centigrade and 70% relative humidity. To calculation of germination percentage and uniformity and time to 5, 10, 50, 90 and 95 percentage of final germination used the Germin program (Soltani et al., 2002).

According to analysis of variance the most traits were significant for wheat cultivars, nettle extract levels and their interaction effects. Seedling length, radical length, radical dry weight, radical to plumule dry weight ratio and mean germination time were a significant increase with increasing levels of nettle extract, so that the highest mean radical length in treatment combination of 30% of the extract concentration in wheat Sardary cultivar (12.46 cm) and lowest in 15% concentration in Azar2 cultivar (9.56 cm) respectively. The highest germination percentage, germination rate and uniformity of germination was obtained in treatment of control extract of nettle and application extract decreased average of quantities traits, so that germination percentage and germination  rate  in  Azar  2  cultivar was less  than Sardary cultivar. The application of  nettle extract led to increase radical length and it could facilitate access to water for plants in lack of humidity condition. Since of radicle the first part of plant that is directly exposed to allelopathic it is likely that effects of allelopathic higher than other traits. Increasing radical length in effect of nettle extract was may be due to probably increased cell division, increase in the amount of auxin-induced radical growth and involved in respiration. The application of extract increased mean germination time in Sardary cultivar but reduced in Azar 2 cultivar. In general, the application of 30% aqueous extract of nettle causes increase radical and plumule length compared to the non-application in both wheat cultivars (Sardary and Azar 2), respectively. The use of high concentrations of aqueous extract of nettle to reduce of percentage and speed of germination and increase the time needed for seed germination. The results showed that have inhibitory potential nettle extract residues on germination of wheat varieties (Azar 2 and Sardary).

One of the main strategies to rebuild natural habitats of medicinal species is cultivation and domestication of plants .but seed dormancy in medicinal plants is one of major obstacles for their cultivation and domestication that should provide field for their cultivation and domestication with breaking seed dormancy. Chilling treatments and Gibberellic acid among suitable treatments for breaking seeds dormancy presented as the most effective treatments of seed dormancy. This research done to evaluate the effect of different treatments of chilling and Gibberellic acid on seed dormancy of medicinal plants Allium altissimum and Rubia tinctorum.

Seed of medicinal species Allium altissimum and Rubia tinctorum were obtained from their natural habitats in Koohdasht city in the summer of 1393. For each species, separate experiments done in a completely randomized design with 14 treatments and 4 repeat so that their seed dormancy. Before the start of the experiment, was used of Hypochlorite due to surface sterilization seeds for 3 minute. Used treatments included chilling treatment in temperature 4 ℃(Control, 10, 20, 30, 40, 50, 70, 90 days), Gibberellic acid treatment in density 200, 400, 600, 800 PPM, integrated Gibberellic acid treatment (400 PPM) with chilling (for 30 days) and integrated Gibberellic acid treatment (400 PPM) with chilling (for 70 days ). Seed samples after applying treatments transferred to Germinator (25 ℃). Counting of germinated seeds 24 hours after of the start of the experiment done and recorded daily by the end of the experiment. Standard germination considered growing root to the 2 mm. at the end of experiment was calculated percent, rate and index vigor seeds.

Results of data variance showed that the effect of different treatments of seed dormancy have likely 1 percent  significant difference on germination percent, germination rate and index vigor of Allium altissimum  and Rubia tinctorum  in surface. Seeds of Allium altissimum and Rubia tinctorum  were without germination in control treatment, also different treatments of Gibberellic acid and chilling  didn’t have  any significant effect on  their seed dormancy for 10 and 20 days. In each two species Allium  altissimum and Rubia tinctorum  gained the highest germination percent respectively 89 and 64 percent, the most germination rate  respectively 11 and 9.5 seed at day and the most index vigor respectively 88 and 154 in chilling treatment for 90 days. It seems  cold condition and wet increase somehow  growth of Hormone in seed of studied species and with making Hormone balance in seed is created the start of germination process . Also it is possible, seed placement at low temperature and then bringing them into normal temperature created temperature shock for coat and splitting seed coat and increasing germination. In this research different destinies treatment of Gibberellic acid on germination of Allium altissimum and Rubia tintorum whether was without effect or had low effect. So in chilling integrated treatmentswith Gibberellic acid, Gibberellic Hormone couldn’t be successor of required chilling for seed dormancy of Allium altissimum and Rubia tinctorum. So another factor likely is effective except Hormone balance between Gibberellic acid and ABA in seed dormancy of these plants.

In recent years, the effect of exogenous organic amendments on soil properties and plant growth characteristics has received renewed attention (Motta and Maggiore, 2013). Although the utilization of mineral fertilizers could be viewed as the best solution in terms of plant productivity, this approach is often inefficient in the long-term in tropical ecosystems due to the limited ability of low-activity clay soils to retain nutrients. Intensive use of agrochemicals in agricultural systems is also known to have irreversible effects on soil and water resources (Weber et al, 2014). Compost is organic matter that has been decomposed and recycled as a fertilizer and soil amendment. Compost can greatly enhance the physical structure of soil. Decomposing organic amendments slowly release nutrients which may be taken up by plants and thus result in improved agroecosystem productivity (Csizinszky, 2002). Vermicompost is currently being promoted to improve soil quality, reduces water and fertilizer needs and therefore increases the sustainability of agricultural practices in tropical countries. Vermicomposting is a process which stabilizes organic matter under aerobic and mesophilic conditions through the joint action of earthworms and microorganisms. The products of vermicomposting have been successfully used to suppress plant pests and disease as well as increase crop productivity (Sadeghi et al, 2014). Cow manure is an excellent fertilizer containing nitrogen, phosphorus, potassium and other nutrients. It also adds organic matter to the soil which may improve soil structure, aeration, soil moisture-holding capacity, and water infiltration (Motta and Maggiore, 2013). Plant density is the number of individuals of a given plants that occurs within a given sample unit or study area. Planting density can impact the overall health of plants. Plantings that are too sparse (the density is too low) may be more susceptible to weeds, while planting that are too dense might force plants to compete over scarce nutrients and water and cause stunted growth (Ibrahim, 2012). Evaluation of germination and biological characteristics of seed is the basic and primary studies in field of medicinal plants cultivation (Canter et al, 2005). Despite of many researches on the effect of organic fertilizers and plant density on different crops, information on the effects of these factors for seed resulting from rootstock of many medicinal plants is scarce, therefore, in this study germination and seedling growth indices of Echium amoenum seeds resulting from the rootstock in different plant densities and in condition of organic and chemical fertilizers was studied.

In order to evaluation of germinaton characteristics and seedling growth of Iranian Ox-Tongue (Echium amoenum) seeds resulting from the rootstock in different plant densities and in conditions of organic and chemical application, a factorial experiment based on CRD design with three replications was conducted in 2014 year, in Ferdowsi University of Mashhad, Iran. The experimental treatments included seeds resulting from treated Iraninan Ox-Tongue with different agronomic factors in farm including 3 plant densities (3, 5 and 10 plants per m2) and 4 different types of organic and chemical fertilizers (10 t.ha-1 compost, 7 t.ha-1 vermicompost, 30 t.ha-1 cow manure, 90 kg.ha-1 nitrogen chemical fertilizer and control).

The results showed that in all studied plant densities, the highest germination percentage obtained from vermicompost treatment. Germination rate in density of 5 plants per m2 and application of compost, vermicompost, cow manure and chemical fertilizers was 6, 43, 49 and 40% more than the application of these fertilizers in density of 3 palnts per m2, respectively. The all studied organic fertilizers decreased the mean germination time compared to control, so that the mean germination time in compost, vermicompost and cow manure treatments decreased 58, 55 and 42% compared to control. The highest radicle and plumule length obtained in density of 5 plants per m2 and compost, vermicompost and chemical fertilizers increased radicle to plumule length ratio 3, 5 and 12% compared to control, respectively. Organic fertilizers are among the most significant resources for development of agricultural soil quality and increase in the yield of different medicinal plants. It has been reported that this ecological inputs provide favorable conditions for plant growth and development through improvement of physical, chemical and biological properties of the soil (Motta and Maggiore, 2013), therefore, it can be concluded that improvement of the most studied traits on germination characteristics of resulting seeds of Echium amoenum in the present study were due to use of organic fertilizers. Fallahi et al., (5) have reported the positive effects of organic fertilizers on the improvement of quantitative and qualitative characteristics in chamomile (Matricaria chamomilla L.). It seems plants compete with each other over scarce nutrients and water in high plant density and cause stunted growth (Ibrahim, 2012). In a study, effect of row spacing 20×40, 30×40 and 30×50 cm on yield and yield components of lemon balm (Melissa officinalis) reviewed and reported the related properties of seeds in treatment of 20×40 cm had the highest value (Saglam et al, 2004). Overall, according to the findings of this study, it seems that application of ecological inputs and use of optimum plant density in cultivation of Echium amoenum, can reduce the damage caused by the use of chemical fertilizers, meanwhile effective in improving the quality and properties of the resulting seeds.

Galbanum is a medicinal plant belonging to apiaceae family. Gum extracted from the root has many medical and industrial applications. Because of indiscriminate exploitations from natural pastures, this valuable medicinal plant that is endangered. Gum extracted from the storage root of galbanum is the most important pastoral products of Iran that exported to European countries in high volume (Eslami Manoochehri, 1994). Many medicinal plants have low germination and growth rate because of ecological computability to environmental conditions and low germination indices in these plants have caused these plants more vulnerable to extinction than other plants (Kandari et al., 2008). Priming is one of the seed improvement techniques that enhance the germination uniformity, germination rate, seed dormancy breaking, stronger seedlings growth of primed seeds especially under stress condition and increase competitive ability against weeds. Nutrient priming is a common technique in this field that used as a beneficial seed treatment. Therefore, seeds are treated with solutions containing nutrient such as phosphorus and zinc (Asgedom et al., 2005). Improve the micronutrient in plant caused to increase the yield and seed micronutrient content (Johnson et al., 2005). This study examines the effect of nutrient priming to improve seed germination and seedling establishment in Galbanum.

This study venture out the effect of nutrient priming to reduce germination problems. The experiment was conducted in Research Laboratory of Faculty of Agriculture of Birjand University in 2010 years. For this purpose, a factorial experiment based on completely randomized design was conducted with 3 replications. The experimental factors were include three levels of prime material (Zinc Sulphate, Magnesium Sulphate and Manganese Sulphate), prime concentration at three levels (0.05, 0.1 and 0.2%) and prime duration at two levels (12 and 24 hours). Early, the seeds were disinfected by 1 percentage of sodium hypochlorite for 5 minutes. Then replaced at 4 degree centigrade for 5 weeks until seed dormancy was removed. After removing the seed dormancy, the seeds were treated with desired treatments. Then, twenty seeds from treated and control replaced in 9 centimeters diameter Petri dishes. The seeds replaced on two layer filter paper within Petri dishes. The Petri dishes were transferred to germinator with 12 degree centigrade temperature and 12 hours light cycle (light and dark). Finally, the germination indices consist of germination rate and percentage, Seed vigor, radicle and plumule length and dry weight were measured.

The results showed that the effect of nutrient priming materials on vigor, radicle length and dry weight (P> 0.01) and plumule length and dry weight (P> 0.05) was significant (Table 1). The treatment with zinc sulfate showed the most vigor. The highest radicle and plumule length was observed in the zinc and magnesium sulphate priming treatments but there was no statistically significant difference in plumule length between magnesium and zinc treatments. Seed treatment with any of the tested materials increased radicle and plumule dry weight compared to control (Table 2). Imran et al (Imran et al., 2008) reported that the nutrient priming of soybean seeds with zinc sulphate, magnesium sulphate and boric acid improves seed germination indices and increase the seed micronutrients content. Also Mirshekari (Mirshekari, 2013) reported that the Marigold seed vigor increased by seed priming with zinc and magnesium micronutrients. Effect of solution concentration on the germination percentage and rate, seed vigor, radicle length and dry weight (P> 0.01) was significant (Table 1). The results showed that all of the traits and characteristics showed the highest average at 0.05 percent concentration and with increasing concentrations to 0.1 and 0.2 percent of priming solutions, the average of all traits were decreased (Table 3). In this regard, Arif et al (2007) reported that increasing the concentration of 0.05 to 0.075 percent in zinc priming solution was reduced the chickpea emergence and biomass. Also reduce germination and seedling length affected by high concentrations of three elements boron, molybdenum and zinc in chickpea, lentil and cowpea have been reported (Johnson et al., 2005) which may be due to toxic effects of high absorbing elements (Bradford, 1995). The results showed that the increase of nutrient priming duration from 12 to 24 hours caused to improve all traits and germination indices in Galbanum (Table 4). Effect of priming duration on germination various between different species, for example increasing the priming duration lead to reduction Aquilegia Canadensis germination while increased Aquilegia caerula germination (Finnerty et al., 1992). In general, the results showed that nutrient priming with zinc sulphate 0.05 percent and 24 hours have been the better results on Galbanum germination and seedling growth.

Weed in terms of the growth and the type of damage that cause and respond to different methods are different, you must first growth behaviors and response to environmental factors, the identification of various weed and then depending on the nature and behavior them the planning to manage the different species. One of the most important factors for successful weed seed germination that various environmental factors such as light, temperature, humidity, soil pH, salinity and drought stress is important, Response weeds varies is considerably in this respect. The competition started a weed that can be effective at an ecological niche. For being a weed able to compete for ecological niche germination is important.  

In order to assess the tolerance of this weed germination and seedling growth of weeds (Cardaria draba) and alyssum (Alyssum Hirsutum) ecotype Karaj to salinity and drought stress two separate trials in a completely randomized design with six treatments and four replications for each weed in weed Research Laboratory Bu-Ali Sina University Hamedan was conducted in 2015. On drought stress by solving a certain amount of polyethylene glycol 6000 for potential (-2, -4, -6, -8 and -10 Bar)  and Salinity by dissolving different amounts of sodium chloride in distilled water to create potential (-2, -4, -6, -8 and -10 Bar) and distilled water for each two experiments were used for without stress conditions. Seed disinfected with sodium hypochlorite (5%) for 2 minutes and then rinse with distilled water for 3 minutes, 25 seed inside diameter of 9 cm plate with two layers of filter paper were placed on the amount of 5 ml of distilled water or solvent with drought and salinity levels that were added to it. At the end of experiment characteristics of such as germination percentage, speed germination, seedling vigor index, seedling radicle and hypocotyl Length and weight were measured treatments.

The results showed that the drought and salinity from zero to -10 Bar decreased significantly (p<0.05) the percentage of germination, seedling vigor index, radicle and hypocotyl length, fresh and dry weight of seedling weeds. With increasing intensity of drought stress from zero to -10 Bar hoary cress and madwort seed germination was reduced 12 and 67 percent respectively compared to control. Madwort weed seed germination under drought stress was more than hoary cress plant. By capture both weed seed germination under salt stress and drought decreased madwort weed in germination was slow. Increased drought stress resulted in reduced seedling vigor in this weed. Highest (3.47) and the lowest (1.30) seedling vigor was observed at the controlled conditions and -6 Bar potential respectively and with increased the drought stress, there was no significant difference. Due to the loss of madwort weed seedlings at the above potential of -4 bars was not possible to measure seedling vigor. The salt stress caused to significant reduction in hoary cress and madwort seedling vigor. This index is a function of the germination percentage and seedling length and the fact that the stress seedling vanished, so the trait was not calculated. With increasing intensity of drought stress, the radicle and hypocotyl weight response in this weed was similar to alyssum. More decreased with increasing drought stress was observed in hory cress radicle. Highest hypocotyl and radicle growth in madwort weed was observed in control and drought stress had stopped growth radicle and hypocotyl seedling to stress and the destroyed after 15 days. According to the results seems to the germinated seeds of hory cress and madwort are highly sensitive to salinity and drought. However, the sensitivity to salt stress was higher the than drought stress in both weed. By comparing the two results show that madwort weed to drought and salinity stress this weed is more sensitive to stress as the minimum amount (-2 Bar) seedling growth processes were stopped.

Asafetida (Ferula assa-foetida) is a medicinal plant belonging to the family of Apiaceae. The economically important part of the herb is the resin known as Asafetida gum which is extracted by cutting the apex. Currently almost 100% of the gum in the market is fully dependent on natural ecosystems. High demand of this species for pharmaceutical industry has made a unique opportunity for farmers to initiate and expand the plant cultivation in arable lands. Issue in seed germination of asafetida is the first step of the domestication process aimed to be resolved. To address the issues, a laboratory and glasshouse research project using a range of osmo-hydropriming treatments was conducted in Mohammadiah Station of Agriculture and Natural Resources Research and Training Center, Southern Khorasan, Iran in 2014.

The laboratory experiment was composed of six treatments (osmopriming with CaCl2 at osmotic potentials of -1 and -2 MPa and with KH2PO4 at -1 and -2 MPa, hydropriming with distilled water and unprimed seeds as control) in four replications based on a Completely Randomized Design. While the glasshouse experiment was set using 3 priming treatments selected from the lab phase results (hydropriming, osmopriming with CaCl2 at -1 MPa and with KH2PO4 at -2 MPa) and unprimed treatment seeds as control. The seeds were treated in glassy beakers containing 150 mlof priming solution (volumetric ratio of solution to seeds was 5) for 12 hours (Van’t Hoff, 1887). Then they were washed with distilled water three times and dried at 20°C in an infected-free medium in laboratory for 12 hours. In lab experiment Petri dishes with the diameter of 10 cm containing two filter papers were used for germination. So 7 ml distilled water was first added to Petri dishes and 15 seeds were placed. They were then kept in a germinator at 14°C and light period of 12 hours for one month. In control treatment, the seeds were placed in Petri dishes after wet chilling without priming. The recorded traits at laboratory phase included germination percentage, germination rate, mean germination time, seedling dry weight, seed vigor, seedling length. In the glasshouse experiment, the pots with the diameter of 10 cm were filled by fine sands and 15 seeds were placed at the top and covered with a one centimeter depth of sand. To make sure that the seedlings have access to nutrients, the pots were watered by hydroponic nutrient solution(Hoagland and Arnon, 1950) once in 3 watering events. In the glasshouse trial, the following traits were recorded: Emergence percentage (EP), emergence rate (ER), seedling dry weight (DW), vigor index (VI), seedling length (SL).

In both experiments the results showed that priming increased germination percentage as compared with control. Among the studied priming treatments at the laboratory, priming with distilled water, KH2PO4  -2 MPa and CaCl2 -1 MPa had the greatest effect on increasing germination percentage of Asafetida seeds. They had significant effects on germination rate as well especially at the seed lot treated by CaCl2 at -1 MPa, reaching to the maximum level of 0.099 (1/day). These three treatments were also successful at glasshouse trial having higher significant emergence percentage and emergence rate than control.  The seed vigor of asafetida received high level of significant positive outcomes with hydroprime and osmoprime (CaCl2 at -1 MPa) in which hydroprime achieved the highest vigor index of 916 at lab experiment. At glasshouse experiment all the priming treatments significantly increased the vigor index and seedling length. Khalil et al. (1997) related the increase in the length of seedling, shoot and root to the increase in germination rate influenced by priming. Seedling dry weight also showed a positive response to the priming treatments. The dry weight was highest (0.1 gram) in the two osmoprime treatments (CaCl2 -1 MPa and KH2PO4 -2 MPa) and was lowest in the other two treatments (control and osmoprime KH2PO4 -1 MPa) with 0.08 and 0.075 gram respectively. In literature, the increase in dry weight is more attributed to the higher growth rate incurred in priming treatments. Cellular and molecular studies showed that priming increase seed capability in improving DNA replication, stimulating RNA activities, enhancing protein synthesis and hormone driven germination. Therefore, when the treated seeds are placed in germination conditions, they show significantly higher germination characteristics than control (Azarnivand et al., 2010). Moreover priming increases the enzymatic activities of the seeds resulted in per-oxidation of lipids resulted in repairing some of the damaged seeds. For instance, Jeng and Sung (Jeng and Sung, 1994) found that free radicals were destroyed by enzymes that were accumulated by higher water absorbed during priming in Groundnut seeds. The overall outcome here showed that seed priming can play an important role to improve seed germination and emergence in Asafetida. Meanwhile between the treatments, hydropriming and osmopriming with CaCl2 at -1 MPa showed to have full significant effects on the traits at both laboratory and glasshouse experiments. Nevertheless as hydropriming uses distilled water instead of chemicals, it will have no negative impact on environment. For this reason in some regions it may be recommended to use hydropriming rather than osmopriming.

The Peanut (Arachis hypogaea L.) is one of the most important and most economical oilseed crops in tropical and subtropical regions, mostly cultivated in order to produce oil and protein (Maiti and Ebeling, 2002; Smartt, 1994). Hydropriming increases viability in peanut seeds (Ponnuswamy and Karivaratharaju, 1993).  Osmopriming peanut seed using calcium chloride increases the percentage of germination. In addition, significant changes can be observed in many germinated seedling characteristics in solutions containing calcium chloride (Datta et al., 1990). Heterotrophic growth of seedlings can be divided into the two components; 1. Weight seed reserves transferred and 2. Conversion efficiency of seed reserves transferred to the seedling tissue (Zeinali and Soltani, 2001; Soltani et al., 2002; Soltani et al., 2006) that this steps is strongly influenced by the quality of the seed (De Figueiredo et al., 2003). Therefore, present study was conducted in order to evaluate the effect of seed priming on germination and heterotrophic growth of peanut seedlings.

The present study was conducted at factorial experiment based on randomized complete block design at Faculty of Agriculture, Islamic Azad University of Rasht. Experimental treatments were 2 levels of seed size (medium and large), 2 levels of priming type (hydropriming and osmopriming) and 4 levels of priming time (30, 60, 90 and 120 minutes). In order to hydropriming and osmopriming of peanut seeds was used distilled water at neutral pH and calcium chloride solution with a concentration of 0.1%, respectively. The experiment was conducted with 150 seeds of each experimental treatment in 3 replicates of 50 seeds. Before performing priming, disinfection of seeds peanuts using mercuric chloride was 1% (Nautiyal, 2009). Time drying primed seeds was half an hour. For standard germination test, each treatment for 10 days at a constant temperature of 25 ° C was the germination germinator. For this test the germination was used from method of between wet papers (Hampton and TeKrony, 1995). Identify and counting of normal and abnormal seedlings from day 5 to 10 was based on ISTA instructions (ISTA, 2011; Don, 2009). On the last day of the test germination, seedlings and its components dried in the oven at 60 ° C for 24 hours (Maiti and Ebeling, 2002). In this study, the Indexes and traits included: Final Germination Percentage, Germination Rate, Mean Velocity Germination, Coefficient of Germination Speed, Mean Germination Time, Mean daily Germination, Coefficient of Uniformity of Germination (Germination Indexes), Total Dry Weight, Seedling Dry Weight, Radicle Dry Weight, Plumule Dry Weight, Hypocotyl Dry Weight, Fragment Seed Dry Weight, Seed Reserve Use Rate, Seed Reserve utilization Efficiency, Seed Use Reserve Fraction (Seedlings Heterotrophic Growth), Radicle Length, Hypocotyl Length, Plumule Length, Seedling Length (Length traits), Seedling  Length Vigour Index and Seedling  Weight Vigour Index.  The data obtained was analyzed using the software MSTAT-C. In addition to analysis of variance, LSD method was used to Comparisons of average data.

The results showed that effect of peanut seed size on all indices (other than coefficient of germination speed) and components of heterotrophic growth was significant (P <0.01). The effect of priming type (P <0.05) showed that the maximum germination percentage (79.17 percent), mean velocity germination, mean daily germination and coefficient of uniformity of germination was related to osmopriming. Effect of priming type in priming time (P <0.05) showed that the maximum Seed Reserve utilization Efficiency and Seed Use Reserve Fraction were in the treatment of osmopriming during 60 minutes. Also, maximum seedling weight vigour index was in treatment of osmopriming during 120 minutes. The effect of seed size, priming type and priming time (P <0.05) showed that the maximum  seedling length vigour and  Seed Reserve utilization Efficiency were in 90 and 120 minutes hydropriming, respectively and  maximum coefficient of germination speed and mean germination time were in 30 hydropriming and 90 minutes osmopriming, respectively. The overall, maximum germination and heterotrophic growth was obtainedin osmopriming with calcium chloride 0.1%. Rangaswamy et al. (1993) and also Narayanaswamy and Channarayappa (1997) showed that the maximum percentage of germination the seeds of peanuts were in calcium chloride of 0.4 and 0.5 percent, respectively. also, Massarat et al. (2013) reported that the germination percentage and other indices of germination were under the influence of priming had significant differences. Use of calcium chloride caused the maximum vigour index in peanuts. Fu et al. (1993) also reported that priming peanuts with calcium chloride has to increase vigour index. In general, osmotic priming to control water absorption, improved the plasma membrane, reducing the loss of electrolytes, improve the vigour in seeds (Koocheki and Sarmadnia, 2007).

Galbanum is a valuable medicinal plant belonging to apiaceae family. Gum extracted from its root there are many industrial and medical applications. Because of physiological dormancy the galbanum seeds have a little germination. Physiological dormancy is common type of primary dormancy in the apiaceae family (Bewley and Black, 1994). To breaking the physiological dormancy depending on the plant species, seeds should be exposed to cold, heat, treated with Gibberllic acid or other chemicals (Bewley and Black, 1994). The effect of cytokinines on the release of seed dormancy has been proven (Sharifi and Pooresmael, 2006). To context for domestication of this plant, conservation of genetic resources and the development of medical and industrial experts, this study carryout to find the appropriate treatments for  galbanum seed dormancy breaking. 

This study was conducted to optimize the methods of galbanum seed dormancy breaking. For this purpose, were used two separate experiments. The first experiment was conducted by a factorial experiment based on completely randomized design with three factor and replications. This experiment factors were consisted of moist chilling duration (0, 2, 3 and 4 weeks), Gibberllic acid concentrations (0, 50, 100, 150, 500, 1000 and 1500 ppm) and type of the breaking dormancy media (sand and filter paper). The second experiment was conducted with similar plan of first experiment. This experiment factors were consisted of moist chilling duration (0, 2, 3 and 4 weeks), benzyl amino pourine concentrations (0, 0.25 and0.35 mg/L) and type of the breaking dormancy media (sand and filter paper). The seeds disinfected by using of 1 percentage sodium hypochlorite for 5 minutes. To apply moist chilling treatment, the seeds replaced within sterile filter paper layers or wet sand media as well as daily watering. Then transferred to refrigerator by 4 degree centigrade temperature.  All samples after the treatments were transferred to a growth chamber with a constant temperature 12 degree centigrade. In each experiment, 20 seeds replaced on the Petri dishes with diameter of 9 cm were used. Germination percentage and rate were measured in this study.

The results showed that moist chilling was essential factor to breaking the galbanum seed dormancy. Moist chilling combined with hormones also improves the germination rate and percentage. In this regard, Zangoie et al reported that the use of Gibberllic acid combined with moist chilling was significantly increased the germination rate of Dorema ammoniacum than the single moist chilling treatment (Zangoie et al., 2013). Also Yamauchi et al (Yamauchi et al., 2004) reported that 4 degree centigrade was increased the gene expression and Gibberllic acid production on the radical and aleuronic layer, thus the combination of moist chilling and hormonal treatments can improve the germination of seeds (Yamauchi et al., 2004).  Between two used hormones, the Gibberllic acid along with moist chilling showed that better seed germination compared to benzyl amino pourine along with moist chilling. Also it was found that use of sand media would have advantages for seed dormancy breaking compare with filter paper media. Stratification in moist sand as a very effective method to seed dormancy breaking on the some species such as Leymus arenariu (Greipsson, 2001).  Sand composed from mineral particles that not allows for rapid decomposition in an attack by micro-organisms during stratification period. On the other hand, appropriate moisture condition in sand media due to gravity water drainage from sand resulted in moisture adjustment to the extent of field capacity, that causes adequate moisture was exist around the seeds (Nasiri, 2008). This study showed that stratification was essential agent to remove galbanum seed dormancy. Application of Gibberllic acid with moist chilling on seed germination was effective than Benzyl Amino pourine with moist chilling. It was also found that the use of moist sand media for galbanum seed dormancy breaking was better than filter paper media.