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Randomized factorial design was implemented in four replications to determine optimal methods of Ajwain (Carum capticum) standard seeds germination in SPCRI. Ajwain seeds were placed top and between paper and sand exposed to two potassium nitrate (two grams per 1000 ml distilled water) and pre-chilling (seven days under 7-10ºC) pre-treatments which were under six temperatures (10, 15, 20, 25, 20-30, and 35ºC) in germinator for 25 days so as to germination indices were assessed. Ajwain seeds viability was estimated 75% after tetrazolium test. The highest final and normal seedling percentages were found under 15 and 20ºC in pre-chilling treatment and also 20ºC in potassium nitrate and control. No germination was observed under 35ºC in potassium nitrate and control, however, pre-chilling led to >26% germination. The higher germination potential was shown in top and between papers compared with sand. The lowest germination rate was recorded in control and potassium nitrate and the highest one in pre-chilling. The maximum of seedling weight vigor was suggested in top and between paper when seeds were put under 10, 15, and 20ºC. In order to evaluate optimal standard germination of Ajwain seeds, it was resulted that applying of two potassium nitrate and pre-chilling treatments placed top and between papers under 15 and 20ºC caused maximum of germination potential and seedling weight vigor. [ABSTRACT FROM AUTHOR]

The deterioration of the seed is a natural phenomenon, and seeds tend to lose quality and viability even under optimal storage conditions. The ability of hydropriming to ameliorate seed deterioration damage was studied in kochia. The experiment was a completely randomized design with four replications. Kochia seeds were subjected to accelerated ageing for 48 hours at 40 °C and then hydroprimed at 20 °C for 1.5, 3 and 4.5 hours. Regardless of duration, hydropriming significantly improved final germination percentage, germination rate, seedling length, vigour index, antioxidant enzyme activities (catalase and superoxide dismutase), soluble sugars and proteins of aged seeds. Mean germination time and malondialdehyde content of primed seeds decreased compared to non-primed seeds. Hydropriming for 1.5, 3 and 4.5 hours increased final germination to 15, 23 and 37 %, germination rate by 45.4, 72.7 and 109 % and superoxide dismutase activityby 8.6, 14 and 27 % compared to non-primed seed, respectively. Thus, hydropriming for 4.5 hours is the most suitable priming period to recover loss of kochia seed quality and to improve germination characteristics of deteriorated seeds. [ABSTRACT FROM AUTHOR]

This paper investigates the effects of cold plasma radiation on the percentage, velocity, average germination per day, germination index, and prose and growth of green cumin roots. A factorial experiment was performed in a randomized design in 5 repetitions. Test factors included pretreatment of cold plasma irradiation time at 0, 3, 6, 9, and 12 minutes by 7 and 14 kV and 800 Hz plasma generators. The results of this work showed that the treatment time and the applied voltage of cold plasma significantly affect the percentage, velocity, average of germination per a day, germination index, and prose and root of the green cumin seed. Among all treatments, a dose of treatment with time of 6 minutes at a peak voltage of 14 kV had the greatest effect on the referred characteristics, except increasing root in which plasma treatment with a dose of 3 minutes has the most effect. Cold plasma has been generated with a dielectric barrier discharge (DBD) is a hand-made and designed in on desk dimensions, in which air is used as plasma active gas.

Plant growth promoting rhizobacteria are a group of bacteria that can actively colonize plant roots and can stimulate plant growth. This study was executed to evaluate of four strains of Pseudomonas fluorescens Migula (PF1-4) and six strains of Pseudomonas putida (Trevisan) Migula (PP 1-6) on seed germination characteristics including germination percentage, germination rate, root and shoot length and dry weight, seed and seedling vigor index and α-amylase activity of pot marigold (Calendula officinalis L.). In vitro production of siderophore, hydrogen cyanide, indole-acetic acid (IAA) and volatile and non-volatile metabolites of bacteria were also determined. The bacterial suspension (109 CFU/ml) was used to inoculate the seeds under aseptic conditions. Results revealed that the metabolites concentrations were significantly different between bacterial strains. Different strains of rhizobacteria had also variable effects on germination parameters and the effect of plant-rhizobacteria interactions on germination characteristics could be positive or neutral. Maximum effects of bacterial strains were recorded for PP-1, PP-2, PP-5, PF-1 and PF-2 strains. The effects of bacterial strains on studied characteristics were significantly correlated with IAA production by bacteria. As a conclusion, the role of biopriming with growth promoting rhizobacteria on germination characteristics and seedling growth were dependent on bacterial species and strains. These results also suggest that the amont of bacterial IAA produced plays a major role in seed germination and may stimulate germination features. [ABSTRACT FROM AUTHOR]

The rapid flowering of bedding flowers, such as petunia (Petunia hybrida L.) and zinnia (Zinnia elegans L.), increases the uniformity of the seedbed and their simultaneous flowering. In this study, the effect of seed priming on the germination and vigor of petunia and zinnia seedlings has been investigated. A factorial experiment was conducted in the form of a completely randomized design with two factors, the first factor, the plant species, and the second factor, three salts of potassium nitrate, calcium chloride, and sodium chloride along with control in the laboratory of the Department of Horticultural Sciences, Faculty of Agriculture, Al-Qasim-ul-Akhra University of Babol, Iraq. The results showed that in both plants, halopriming treatment with 50 mM potassium nitrate and calcium chloride for 24 hours provided better results in terms of germination and seedling growth. Between the two treatments of potassium nitrate and calcium chloride, there was no significant difference in the characteristics of time to reach 50% germination, average germination time, germination index, final germination, and wet and dry weight of roots and shoots of petunia and dry weight of zinnia shoots. In general, the findings of this study will be important in understanding the direct physiological effect of halopriming in increasing seed germination and seedling establishment in petunia and zinnia and can provide detailed information about the potential effectiveness of priming with potassium nitrate and calcium chloride to the seed industry. [ABSTRACT FROM AUTHOR]

Caper, Capparis spinosa, has medicinal, edible, and industrial uses and has been used since ancient times to treat kidney, spleen, liver, paralysis, gout, and rheumatism diseases. Dormancy caused by hard seed shell is one of the problems of seed germination in this plant. In order to study on improving seed germination methods and biochemical characteristics, a factorial experiment on the basis of completely randomized design was conducted with three replications. To improve seed germination, four caper populations (Tehran, Torbat-e-Jam, Firuzabad, and Barazjan) were treated with six seed treatments (control, ultrasonic, potassium nitrate, gibberellic acid, chilling, and scarification). Phytochemical characteristics of the populations were also compared. The results of phytochemical traits showed that the Torbat-e-Jam population had the highest antioxidant activity with an IC50 equal to 26.4. The highest amount of total phenol equal to 227.03 mg of gallic acid per gram of dry extract, and total flavonoid equal to 71.54 mg of quercetin per gram of dry extract was obtained from Tehran population. The results showed that the highest percentage of germination with 62% and the highest germination rate with 3.5% per day was identified in the treatment of Firozabad population under scratching conditions. Also, the results of this study showed that in Tehran, Torbat-e-Jam, Firozabad, and Barazjan, the percentage of germination increased by 6.55, 7.25, 3.44, and 11.25 times, respectively compared to the controls. According to the results of the current study, seed scarification is recommended to increase the germination rate of a caper valuable medicinal plant. [ABSTRACT FROM AUTHOR]

Eryngium caucasicum is one of the important endemic plants in the northern provinces of Iran. Few studies have been done in relation to its germination. Studying its domestication and propagation can play an important role in preserving and commercializing. To evaluate seed germination and plantlet vigor of Eryngium caucasicum, a laboratory experiment was conducted as factorial based on a completely randomized design in 3 replications with two factors, temperature (5, 10, 15, 20, 25 and 30 °C) and stratification (0, 1, 2, 3 and 4 weeks). According to morphological studies, the thousand seed weight of Eryngium small seeds was estimated 1.45 g and a moisture content of 24%. The average of flowers per plant is 11.3 and the average of seeds per fruit is 56. The highest germination percentage (74.6), germination rate (1.25), germination uniformity (0.21), and seed vigor (2.2) are shown at 15°C without stratification. The highest germination energy and the shortest germination time (15.26) were observed in 20°C without stratification (64), which is not significantly different from the treatment of 15°C (63.3). In general, the results of the experiment showed that Eryngium seeds germinate at temperatures between 15 and 25 °C, and no germination was observed at temperatures of 5, 10, and 30 °C, and the best temperature for Eryngium germination is 15 °C without stratification. [ABSTRACT FROM AUTHOR]

Background and Objectives: Quercus brantii L. has been classified as a vulnerable species, the most widespread and pure types of which are observed in the southern and middle Zagros. Due to the elimination of natural regeneration, caused by excessive livestock grazing, collection of tree seeds, mortality of forest, and habitat destruction, several studies have been carried out to address barriers to natural regeneration in the oak forests of Zagros. Yet, the lack of regeneration in these forests still exists. In this study, we examined several methods of natural regeneration based on simple consideration of soil moisture preservation for the establishment of natural regeneration of brant's oak. Materials and Methods: this study was conducted in Alamdar Strait in Behbahan province in 2018. For this purpose, oak seeds were planted in winter with five replications under several treatments, including stone shelter, under the mother tree, open ground, using superabsorbent and curved pits on a slope gradient of 10-55%, the elevation of 850-975m and different geographical directions. Seeds were washed with water and sterilized with 70% ethanol before cultivation. Then, they were placed in distilled water for 48 hours prior to planting. At the end of the growing season, the survival rate of the seedlings and their height were measured and their correlation with environmental factors was determined. Results: The results indicated that 25.24% of the germinated seeds were able to survive in harsh environmental conditions until the end of the growing season. The superabsorbent treatment had the highest germination rate of 82% with the lowest survival rate of 6%. While the stone treatment had the lowest germination rate of 38% with the highest survival rate of 31%. The western slopes had the highest germination rate of 77%, but ultimately 29% of seedlings in this range survived. Although, 71.4% of the seeds germinated in the northern slopes, only 31% of the seedlings survived at the end of the growing season. Seeds planted on the ridge treatments had the lowest germination rate of 50% and survival rate of 14%. The results also showed that the effects of slopes and altitudes were not significant on the survival rate of seedlings. Seedlings planted under the shelter of trees had the highest seedlings height, while the lowest seedling height was recorded for seedlings under the curved pits. Conclusion: In general, the sowing of oak seeds can have acceptable results in the improvement of oak forests. In other words, the results could be useful for obtaining higher performance on the survival and growth of direct sowing of oak seeds. [ABSTRACT FROM AUTHOR]

Gaseous molecules hydrogen sulfide (H2S) and salicylic acid (SA) enhance plant acclimation to environmental stresses such as salt stress. In the current study, the effects of priming of alfalfa seeds with sodium hydrosulfide (NaHS) (0.75 mM) as H2S-donor or SA (0.75 mM) on the improvement of germination indicators and the growth of seedlings under salt stress (0, 25, 50 and 100 mM) and also the decline of oxidative damages caused by salt stress (0 and 50 mM) were evaluated. The results showed that under unprimed conditions, salt stress had negative effects on different indicators of alfalfa seed germination and also on the growth of alfalfa seedlings. In addition, under unprimed conditions, the accumulation of malondialdehyde (MDA) and hydrogen peroxide (H2O2) significantly increased under salt stress. NaHS-priming and SA-priming showed positive effects on germination indicators and root length significantly increased in the seedlings obtained from NaHS- or SA-primed seeds. NaHS-priming and SA-priming decreased the accumulation of MDA and H2O2 under salt stress conditions showing the effect of priming treatments in decreasing oxidative stress. In addition, in response to salt stress, NaHS-priming and SA-priming significantly increased the levels of total sugars (especially 1 and 3 days after germination), when compared with their levels under unprimed conditions. Therefore, NaHS-priming and SA-priming treatments enhance plant responses in the first days after germination against salinity by reducing oxidative damages through activation of the antioxidant defense systems.

To investigate the effect of drought stress and foliar application of ascorbic acid, salicylic acid and methanol, and post-harvest seed deterioration, two separate experiments were carried out as split plot based on randomized complete block design with three replications on maternal plants in field conditions and a factorial based on completely randomized design considering by using seed under storage conditions. The main plots were consisted of three irrigation levels, irrigation after 60 mm evaporation from basin, considered as control treatment (optimum irrigation), cessation of irrigation at flowering and silique stages, and sub plots consisted of 10 levels of foliar application, (100, 200, 300 mg.lit-1 ascorbic acid, 100, 200, 300 μmol salicylic acid, 10, 20, 30 vol% methanol and the foliar application with distilled water as control treatment). Seeds obtained of maternal plant were evaluated under no-storage (control) and storage at 40°C for one month. The results showed that foliar application of ascorbic acid (300 mg.lit-1) increased seed yield by 29% under optimum irrigation as compared with non foliar application under the same irrigation condition. Cutting off irrigation of maternal plant decreased radical and plumule weights under both no-storage and one-month storage conditions. The maximum germination percentage belonged to foliar application of ascorbic acid (300 mg.lit-1) under optimum irrigation condition at both no-storage one-month stored seed. The minimum germination percentage belonged to no use of growth regulators application and cessation irrigation at flowering stage. Maternal plants which sprayed with ascorbic acid contained the highest seed weight vigor index at all irrigation treatments.

Background and objectives: One of the main causes of plant growth and development disorders, is lite presence of adverse environmental conditions such as drought. It leads to stress in plants and endangers their survival. Recent research recommends the use of soil microorganisms, especially plant growth-promoting bacteria, which are involved in plant growth as well as the nutrient cycle in the soil. Through which the negative effects of environmental stresses are reduced. The present study was conducted to investigate the effect of plant growth promoting bacteria on germination, growth and uptake of some nutrients in Dactylis glomerata L. under drought stress. Methodology: The research was conducted as a factorial experiment based on a completely randomized design. The first factor of biofertilizer application was considered at four levels, the control (C, no biofertilizer was used in this treatment), A= Azotobacter vinetandii, P = Pantoea aggtomerans+Pseudomonas putida and A ا P (combined use of Azotobacter and Pseudomonas). The second factor was drought stress, which was considered at three levels and included FC (field capacity), 0.4 field capacity (0.4FC) and 0.7 field capacity (0.7FC). For inoculation of biofertilizers (in powder form), half a gram of each pure fertilizer was dissolved 0.5 Li water and the seeds were impregnated with a solution. To apply drought stresses, soil field capacity was first determined using the weighting method. Then, on the calculated base number for field capacity, the amount of water required to apply drought stress was determined. To measure germination percentage and rate, seedlings were counted daily. Plant species were harvested after 90 days. Stem and root length, plant dry weight and uptake of nitrogen, phosphorus, potassium, zinc, iron, manganese by the plant were measured. Multivariate analysis of variance was analyzed using SPSS software. Duncan test (5% level) was used to compare the means. Results: The results showed that the highest and lowest germination were related to treatment A at the level of 0.7FC and control treatment at 0.7FC, respectively. A+P treatment compared to the application of fertilizers had less effect on reducing drought stress on the plant germination. The maximum stem and root length and plant dry weight were related to Aztobacter treatment at 0.4 stress. While P treatment at 0.4 stress had the lowest root and stem length and plant dry weight. Maximum potassium uptake by the plant was measured in treatment A under FC conditions and the highest amount of iron and zinc in Pseudomonas application was measured at 0.7FC. A+P treatment at 0.4 stress showed the lowest absorption of iron, zinc and manganese. In general, the results showed that the use of Azotobacter is more effective in reduction of drought stress in D. glomerata L. compared to Pseudomonas. Also, separate use of the bio-fertilizers has a greater effect on reducing the effects of drought stress on the plant compared to combination treatments. Conclusion: In general, drought stress significantly reduced lhe growth of D. glomerata L. The use of growth-promoting bacteria by reducing the negative effects of drought improved growth and plant establishment in drought stress conditions. Azotobacter increased germination, plant dry weight, root and stem length. Pseudomonas also reduced the effect of drought stress on plant growth. Compared to Azotobacter, application of Pseudomonas had less effect on reducing the effects of drought on plant growth. In order to improve the growth and yield of the plant in dry conditions, inoculation of seeds of this plant with Azotobacter is recommended. [ABSTRACT FROM AUTHOR]

Persian honey locust(Gleditsia caspica Desf.) is an endemic tree in the northern forests of Iran and southeastern Azerbaijan, which has low seed germination because of water impermeability of seed. In this research, effects of hot water at 70 °C and 100 °C (5, 10, 15 and 20 minutes), dry heat at 60 °C, 80 °C and 100°C (15, 30 and 60 minutes) and sulphuric acid treatment at two concentrations of 70% and 98% (at immersions of 5, 20, 40 and 60 minutes) were studied on the characteristics of seed germination of this species. Experiment was carried out based on completely randomized design in three replicates. No germination was observed in the seeds treated with hot water (100 °C), dry heat and control, while the seeds treated with semi-hot water (70 °C), sulphuric acids of 70% (60 minutes) and 98% (20 and 40 minutes) obtained 20, 84 and 100 percent of germination, respectively. In general, hot water, warm water and dry heat are not good treatments for seed germination of Persian honey locust seed. It suggests that for seed dormancy breaking as well as seedling production of Persian honey locust,sulfuric acid 98% (with immersion of 20 or 40 m.) to be used.

Iranianborage (Echium amoenum) is one of the most important plants of Boragicaceae. In order to determine the most suitable method of overcoming seed dormancy of this plant, the present study was conducted in two different experiments. The first experiment was carried out using seeds collected from Mashhad and Javaherdeh based on a factorial study with three replications. Pretreatments were seed treatment at 4° C for 7, 14, and 21 consecutive days under refrigerated temperature, seed treatment with 500 ppm gibberellic acid for 24 hours, and seed treatment with 50% sulfuric acid for 10 minutes. The second experiment was conducted in a randomized complete block design in time and location in two years and two locations of Gorgan and Mashhad. The experiment was carried out to evaluate the effect of climate on quantitative and qualitative characteristics of the flower. Results showed that Iranian borage seed has physiological dormancy since the maximum seed germination percentage was obtained by applying pre-cooling treatments in 7 days. Comparison of the two locations revealed more favorable flower yield and secondary metabolite accumulation (anthocyanin, antioxidant, phenol and flavonoid) in plants cultivated in Mashhad region. Therefore, due to the relative resistance of the plant to water deficit, the cultivation of this plant in Mashhad is suggested to be further evaluated. Also, pre-treatment of 7 days of moist chilling is also recommended to facilitate the germination uniformity.

Gaseous molecules hydrogen sulfide (H2S) and salicylic acid (SA) enhance plant acclimation to environmental stresses such as salt stress. In the current study, the effects of priming of alfalfa seeds with sodium hydrosulfide (NaHS) (0.75 mM) as H2S-donor or SA (0.75 mM) on the improvement of germination indicators and the growth of seedlings under salt stress (0, 25, 50 and 100 mM) and also the decline of oxidative damages caused by salt stress (0 and 50 mM) were evaluated. The results showed that under unprimed conditions, salt stress had negative effects on different indicators of alfalfa seed germination and also on the growth of alfalfa seedlings. In addition, under unprimed conditions, the accumulation of malondialdehyde (MDA) and hydrogen peroxide (H2O2) significantly increased under salt stress. NaHS-priming and SA-priming showed positive effects on germination indicators and root length significantly increased in the seedlings obtained from NaHS- or SA-primed seeds. NaHS-priming and SA-priming decreased the accumulation of MDA and H2O2 under salt stress conditions showing the effect of priming treatments in decreasing oxidative stress. In addition, in response to salt stress, NaHS-priming and SA-priming significantly increased the levels of total sugars (especially 1 and 3 days after germination), when compared with their levels under unprimed conditions. Therefore, NaHS-priming and SA-priming treatments enhance plant responses in the first days after germination against salinity by reducing oxidative damages through activation of the antioxidant defense systems. [ABSTRACT FROM AUTHOR]

This study was aimed to investigate the effects of seed biopriming with plant-growth-promoting bacteria (PGPB) on some characteristics of germination and growth of Astragalus ovinus Boissunder drought stress. This study was conducted as a factorial experiment in a completely randomized design, with three replications. Percentage, rate of germination, mean germination time, vigor, chlorophyll a, b, carotenoids, fresh and dry weight of radicle, shoot, embryonic leave, seedling and radicle length, shoot and seedling were determined. Plant-growth-promoting rizobacteria at five levels including Pseudomonas aeruginosa (Schroeter) Migula, Azospirillum lipoferm (Beijerinck) Tarrand, Bacillus cereus Frankland, Azotobacter chroococcum Beijerinck and the control treatment were considered as the first factor. The second factor was applying drought stress at four levels of 0.0, -0.2, -0.4 and -0.8 MPa. Among the four biopriming treatments tested, A. lipoferm and A. chroococcum were eliminated, because the seeds were failed to germinate and identified as agent pathogenic. Results indicate that the use of these two PGPB increase the characteristics of germination (percentage, rate of germination, mean germination time and vigor) and growth (fresh and dry weight, length and photosynthetic pigments) of A. ovinus. It can be concluded that these two bacteria increase effectively the growth of A. ovinus under different levels of drought stress. In general, these two bacteria play a role in reduction of the negative effects of drought stress on A. ovinus.

Introduction and purpose: Effluent of wastewater treatment plant after reaching to the standards is commonly used as the source of irrigation in agriculture in many developing and developed countries. Before using wastewater in agriculture, it is better to evaluate the phytotoxic effects of wastewater on crops. Therefore, the main objective of this study was to evaluate the impacts of raw and treated hospital wastewater on seed germination and growth parameters of selected vegetable species. Methods: In this study, the toxicity effects of different concentrations (i.e., 0%, 10%, 30%, 50%, 70%, and 10% v/v) of raw and treated hospital wastewater on seed germination, root growth, as well as stems and leaves of three vegetables, namely Coriandrum sativum, Anethum graveolens, and Lepidium sativum, using Petri dish cultivation method were studied through three replications in a completely randomized design. The parameters, such as germination percentage, germination rate index, and growth parameters (i.e., the length of the root, shoot, and leaf), were calculated after 0-10 days. In addition, Biochemical Oxygen Demand, COD (Chemical Oxygen Demand), Toxic Shock Syndrome, pH, Total Dissolved Solids, EC (Electrical Conductivity), free chlorine residual, and microbial quality of wastewater were analyzed in the present study. Results: Obtained results showed that no significant relationship was observed between the control, as well as raw and treated wastewater samples, in seed germination capacity. According to the finding, the length of the root, shoot, and leaf increased with an increase in the concentration of wastewater. Therefore, hospital wastewater had no negative effect on the seed germination of the plants. Conclusion: Hospital wastewater can contain hazardous substances, such as pharmaceutical residues, chemical hazardous substances, pathogens, and radioisotopes. In this regard, it is required to investigate more qualitative parameters regarding the reuse of hospital wastewater in agriculture.

Introduction Planting date is one of the important issues in agronomy that could be changing quantitative and qualitative characteristics of crop seeds. Planting date changes seed quality by providing different environmental conditions such as temperature, relative humidity, day length, radiation, and incidence of pathogens. It is also effective on seed yield. It affects duration of growth and development. A suitable planting date leads to optimal utilization of climatic conditions such as temperature, humidity, day length. It is also important for flowering and grain filling period to take place at the same time with favorite environmental conditions. As a result, it can improve seed yield and seed quality. Some factors such as high temperatures, frequent wetting and drying of air, high relative humidity, and continuous rainfalls have a significant negative effects on seed quality. These conditions during seed development reduce seed quality in the field. It is obvious that such conditions can be occurred on both early and late planting dates. Thus, according to an important role of planting date in determination of seed yield and quality, in this study the effects of environmental conditions during seed filling period on seed yield and quality of mungbean (Vigna radiata L.) were evaluated by implementing different planting dates in field conditions. Materials & Methods This experiment was conducted as a randomized complete block design with three replications at Agricultural Research Station of Gonbad during 2010, which is located at three kilometers northeast of the city, with latitude and longitude of 37˚16́ N and 55˚12́ E, respectively, and a height of 45 meters above sea level. In this study, the genotype VC-1973A was cultivated in five planting dates. The planting dates included April 21, May 10, June 3, June 20 and July 12. The mungbean developmental stages were divided into three stages includes planting to flowering (PD-R1), flowering to beginning of seed filling (R1-R5), and beginning of seed filling to seed maturity (R5-R7). Afterwards, the relationship between the length of these developmental stages and environmental factors (temperature, relative humidity, rainfall and photoperiod) occurring during these stages were evaluated in terms of yield and seed quality. Seed quality was determined via germination, accelerated aging, Electrical conductivity tests, and field emergence percentage. Data analysis was performed by SAS 9.1.3 (Institute, Inc), and Excel 2007 was used to draw figures. Results & Discussion The results showed that seed quality increased as a result of delayed planting date, whereas seed yield decreased. Germination of the aged seeds increased by 0.23% per day of delay in planting. On the other hand, the electrical conductivity per day of delay in planting decreased by 0.43 µs.cm-1.g-1 which reflects the increase in seed vigor. Delaying the planting date led to an increase in field emergence percentage of about 0.23% per day. In fact, in this study the lowest seed quality was observed for planting date April 21 (first planting date). The reason for this occurrence can be related to occurrence of very high temperatures (more than 40°C) and rainfall during seed development (R5-R7). Although the average air temperature during R5-R7 increased in the next planting dates, but the number of days that temperature was more than 40°C decreased, which consequently led to increased seed quality. Also, the length of R5-R7 decreased by delay in planting date, so filling period (R5-R7) was exposed to environmental factors (particularly high temperatures) for a shorter period. In contrast to seed quality, seed yield decreased linearly with delay in planting date. The highest seed yield (1144.4 kg.ha-1) was achieved in the first planting date (April 21). Then, for each day that planting date was delayed, seed yield decreased by 10.84 kg.ha-1, and finally in the last planting date (July 12) reached the lowest amount (299 kg.ha-1). Reduction of the length of developmental stages (especially R5-R7) was the most important cause of seed yield loss. Conclusion Although, delay in planting date increased seed quality of mungbean, this delay reduced seed yield. Seed yield in the last planting date decreased 845.4 kg.ha-1 compared to the first planting date. In fact, delay in planting date decreased seed quantity, but increased its quality. The optimum planting date is the date that maintains the seed quality at a satisfactory level and produce high seed yield, simultaneously. Therefore, planting of mungbean in mid-June may lead to higher seed yield, as well as production of high-quality seeds

Judas tree (Cercis siliquastrum L.) is a suitable species for improving the soil nitrogen fixation and creating the natural landscape in parks and roadsides. This study was aimed to investigate the growth, development and drought resistance of Cercis seedlings by applying different irrigation periods. First, the seeds of Cercis were treated to germinate and reach to seedling phase (30 cm in height) for 90 days. Then, the seedlings were examined in a completely randomized design with four irrigation periods (4, 8, 12, and 16 days) and three replicates for 70 days. Irrigation significantly affected all morphological characters whereas stem length, root length, specific leaf area, shoot dry mass, leaf dry mass (p≤ 5%) and other characters (p≤ 1%) were different among the irrigation periods. The highest stem length, collar diameter, leaf number, leaf area, shoot dry mass, leaf dry mass, collar diameter growth, height growth and survival rate were observed in 4-day irrigation period. Seedlings with 8-day irrigation period had the greatest root volume, root dry mass and plant dry mass. This is while that, the 8-day irrigation period induced the greatest root length, specific leaf area and root/shoot ratio. The results revealed that the 4-day irrigation period was suitable for raising the Cercis seedlings; however, due to the satisfactory survival and growth, as well as the low cost and easy maintenance of seedlings, the 8-day irrigation period can be a good alternative for seedling production of this species.

The present study was conducted to test the effect of Ascophyllum nodosum extract on the growth of Robinia pseudoacasia L., ornamental tree. In vitro and ex vitro clonal multiplication of Robinia pseudoacasia L. was achieved using embryonic axes and seeds as explants, respectively. Factors affecting shoot and root production of R. pseudoacasia L. were investigated by comparing various growth regulators [α-naphthalene acetic acid (NAA) and 6-benzylaminopurine (BA)] and culture media [Murashige and Skoog (MS) and WPM (woody plant medium)] on in vitro conditions, also culture beds (sand, perlite, compost and cocopeat) with different ratios and extracts of brown seaweed Ascophyllum nodosum on ex vitro conditions. Both of BA and NAA were used at concentrations of 0, 0.5, 1 and 1.5 mg l-1. Concentrations used from extracts of A. nodosum were 0, 1000, 2000 and 3000 mg l-1. The optimum plant growth regulator (PGR) combination for maximal plant height, shoot number, node number, root number, root length, leaf number, fresh and dry weight on in vitro condition was 1 mg l-1 NAA and 1 mg l-1 BA in MS medium. The 1000 mg l-1 of extracts of A. nodosum led to optimum plant height, node number, longest root, leaf number, dry weight, fresh weight. The most appropriate plantlets survival on ex vitro condition was observed when the culture medium was a bed containing sand + perlite + compost with proportion of 1:1:1. About 75% of the propagated plantlets and 90% of the micropropagated plantlets were established successfully in acclimatization medium. Regenerated plantlets were morphologically identical with mother plants. Present study showed positive modifications in shoot proliferation, rate of rooting of stem and some morphological and physiological characters due to subjection of R. pseudoacasia L. to optimum treatments.

In this study, the relationship between altitude, climate and soil characteristics as important and effective factors on the growth characteristics, seed germination and essential oils of Ziziphora clinopodioides were examined. Three habitats of this species with different altitudes were selected in Alborz and Mazandaran provinces. Growth characteristics of Z. clinopodioides bushes in 45 plots located at the three habitats were recorded. Seed of this species collected from three habitats and their viability was determined. Three soil samples were taken from each habitat and some physical and chemical characteristics were measured. Analysis variance results of data showed that there is a significant difference among the three habitats from the viewpoint of growth characteristics, soil features and common combinations of essential oils. The highest seed viability was obtained for Rineh habitat with chilling and scratching seed coat. The most important environmental factors affecting the vegetative characteristics and essential combinations was determined using principal component analysis. The results showed that annual temperature, absolute minimum temperature, maximum temperature of the warmest month, number of frost days, altitude, electrical conductivity, moisture saturation, organic matter and soil texture had the greatest impact on these properties.

In order to break dormancy and germinate the seeds of Caucasian maple, they were collected from altitude of 1900 m of Googli Forest located in Savadkooh (north of Iran). Following pre-treatment of warm stratification (0, 4, 8, 12 weeks with 20°C), the seeds were soaked for 24 hours in two separate examinations 1) GA3 (0, 250, 500, 1000 mg/lit) and 2) H2O2 (0, 1, 2, 3%) and immediately moved into cold stratification environment (4°C, for 41 weeks, with consideration of warm stratification period). Both examinations were carried out as factorial with three replicates based on completely randomized design. Water absorption test revealed that in spite of the hard coat, the seeds were permeable to water. Results emphasized the positive effects of warm pretreatment on germination characters, whereas seed germination increased from 13 to 76% and germination speed from 1.4 to 3.8 unit/week. However, the lag time decreased from 20 to 13 weeks and germination period of 50 percent of seeds (T50)from 10 to 6 weeks. Influence of GA3 and H2O2 increased with increase of concentration as well as warm stratification period, whereas GA3 in 500 and 1000 mg/lit was 64% and H2O2 in 2 and 3% was 56 and 73%, respectively. With increasing warm pre-treatment period, the general trend of germination speed enhanced in all concentrations of both promoters. Generally, stratification (warm-cold) without using the promoters mentioned here is easier and more economic for dormancy breaking of Caucasian maple seed.

A vast area of Iran is covered by sand dunes. Biological control is an appropriate method for sand dune fixation. So, it is essential to recognize characteristics of psammophyte plant species and introducing suitable species for sand dunes. Ammodendron persicum is one of the important and compatible species in desert ecosystems. The current research was carried out to investigate the effect of different treatments on seed dormancy breaking and germination stimulation of Ammodendron persicum in order to determine the most effective treatment in enhancing of germination and primary growth of seedlings. The experiment was done in a completely Randomized Design. Our experimental design was included10 random attendance namely: soaking of Ammodendron persicum seeds in gibberellic acid (300ppm) for 48 hr, seed scratching scarification with acid in two interval times of 20&30 min, incorporation of later with sand paper scratching scarification, seed scratching with gibberellic acid (300ppm) and time period of 48hr Ammodendron persicum seed sand papering combined with gibberellic acid soaking, wetting Ammodendron persicum seeds with high temperature water (80°C) for 5&10 min then scratching them by sand paper and also using distillated water as control treatment evidence. Experimental results showed, 30 minutes sulfuric acid soaking combined with sand papering can increase germination to 90% of the laboratory. In addition, seed scratching with gibberellic acid (300ppm) and time period of 48hr Ammodendron persicum seed sand papering combined, wetting Ammodendron persicum seeds with high-temperature water (80°C) for 5&10 min, the percentage of germination, respectively, 45/15, 45/8, 17/10 and 68/28 respectively. Moreover, 30min high-density sulfuric acid caring improves Ammodendron persicum, seed vigor, the power of greenhouse and lab samples to 450 and 510 respectively. Finally, authors reported scratching and acid soaking combination as an efficient, caring method in this research.

Introduction: Weeds limit crop growth, development and yield through competing. Seed bank of weeds in field is one of the sources which can affect weed management and their control methods. Environmental conditions during seed maturation and following dispersal interact to influence the germination phenology of many species. Disturbance plays a key role in the maintenance of habitat for many plant species, particularly referrals, for example, fire ephemerals, desert annuals, and arable weeds. Seed germination and emergence depend on endogenous and exogenous factors. Viable seeds are dormant when all environmental conditions are appropriate for germination but seeds fail to germinate. Thus, dormancy plays an important ecological role in preventing seed germination, being a major contributor to seed persistence of some species in soil. Buried seeds of annual weeds are certainly subjected to different soil moisture conditions during their dormancy release season (winter) according to the annual rainfall pattern and burial depth. Shallow buried seeds are exposed to soil moisture fluctuations that could affect their dormancy status. Laboratory studies showed that desiccation and subsequent re-hydration of seeds could stimulate germination and modify seed light requirements. Seeds buried in deeper layers of the soil would not be exposed to such fluctuations in soil moisture, but would be exposed to different soil moisture environments depending on weather and soil characteristics. The effects of interactions between temperature, and soil or seed moisture, on seed dormancy changes have been reported for several species. Therefore, the objectives of this study were to determine the effect of time and burial depth treatments on seed germination and seedling emergence of Aegilops cylindrica, Agropyrom repens, Avena fatua, Bromus dantoniae, Cynodon dactylon, Cyprus rotundus, Setaria viridis, Anthriscus sylvestris, Centurea cyanus. Materials and Methods: In order to evaluate the effects of time and burial depth on breaking seed dormancy and percentage of germination of 27 dominants weed in Shahrekord region, an experiment was conducted at the research field at Shahrekord University in 2013. The experimental design set as factorial based on completely randomized design with three replications. Treatments consisted of three burial time levels (1, 2 and 3 months) and 4 burial depth (0, 5, 15 and 25 cm from surface soil layer) after 1, 2 and 3 months of burial. Results and Discussion: Results showed that the time and the depth of burial treatments had significant effect on breaking seed dormancy and germination percentage. Seeds retrieved from the soil surface showed highest dormancy percentage and breaking dormancy with increasing the depth and time of seed burial. The results showed that the effects of three burial times, burial depth and interaction of burial time and burial depth had significant effects on dormancy breaking and germination of weed seeds. The bitter herbs of expression and parsnip, the highest percentage of seed dormancy breaking. Germination of Geobelia alopecuoides and Anthriscus sylvestris was observed from seed burial depth of 15 cm. However, the germination percentage, between two and three seed burial months, did not show any significant difference. In this study, Convolvulus arvensies, Rumex acetisella and, Avena fatua in the highest depth (25 cm) had the maximum seed germination. Tillage would bury weed seeds and may help to preserve some seeds, because the seeds on the soil surface or near it, are prone to hunting or decay that eventually, their number is reduced in the soil seed bank. Weed seeds of Centurea cyanus, Geobelia alopecuoides, Turgeniala tifolia, Tragopogon collinus, Bromus dantoniae and Anthriscus sylvestris had more germination percentage with increasing depth to 15 cm, but beyond this depth due to the negative impacts of increased depth, seed germination declined sharply. In fact, the results of this study showed that, based on vertical distribution of seeds, at depth of more than 15 cm, weeds seed germination would be prevented. Seeds for germination, requires special conditions of temperature and moisture, and for this seeds, probably favorable conditions for germination were obtained between soil surface and 15 cm of burial depth. Overall, after two months of burial depth of 15 cm, weed seed showed highest breaking dormancy and germination percentage.

To assess seed dispersal by domestic herbivores (sheep and goat) in Central Zagros region, 12 different rangeland sites, located 200 km west of Isfahan city, were studied. For each site, a pooled dung sample of 10 freshly pellet groups from domestic herbivores was collected in four different periods (mid June, July, August and September) during grazing season (in total, 48 pooled dung samples). Dung samples were dried in a dark room by exposing to open air, and then from each a 150 gram sample was kept for two months in the refrigerator at 3ْc as cold treatment. Seed content of dung samples was assessed in a greenhouse germination experiment over a period of 8 months. In total, 2039 seedlings from 50 different plant species (16 families and 48 genera) were germinated from dung samples. Seed content of dung samples was mostly composed of palatable herbaceous species with no dispersal mechanism or adaptation except for the production of many small-sized seeds. The highest and the least number of germinated seeds was observed in July and June samples, respectively. Also, the highest and the least number of seed species was recorded in September and June samples, respectively. However, only a significant difference in seed species composition was observed between dung samples of September and June. Given that most of the plant species recorded in the region’s vegetation were regenerate by seed, seed dispersal via domestic herbivore dungs may have significant role in natural regeneration of the vegetation, if other environmental and management conditions are met. The results of the present research can be especially applied to reclamation of the country’s rangeland ecosystems.

In recent years, spring late coldness has caused a lot of damage to mountain ashseedlingsin the mountainous nurseries. This research aimed to reduce mountain ash seedlings damage due to spring late coldness. The research was carried out during 2007 and 2008, in Darzikola nursery (Farim Wood Co.), located 17 kilometers far from southeast of Pol-e-Sefid city of Mazandaran province of I.R. Iran. Seeds were treated by two levels of seedling cover (nylon sheet and control), and four levels of seed sowing dates (Fourth week of February (1), first week of March (2), fourth week of March (3) and second week of April (4)) under split plots design with three replications. The trial was repeated for two years. Results showed that effects of sowing date on seed germination rate were significant (p

Drought stress can play an important role in limiting crop productivity and disturbing different stages of plant growth especially at seed germination in arid and semiarid regions. Breeding for drought tolerance at germination stage can enhance the number of seedlings, resulting in a higher yield of grain in rapeseed. In this research 32 cultivars of rapeseed were evaluated for drought tolerance induced by Polyethylene glycol at germination stage according to factorial experiment, based on a completely randomized design with four replications. Osmotic drought stress treatments in four levels including distilled water, -5 and –10 bar was created according a preliminary test. Results indicated high significant differences among cultivars, drought stress levels and their interactions. Drought stress not only decreased germination percentage but also reduced seedling growth. Based on principal component analysis, the first two components named germination potential and seedling growth. Distribution of genotypes based on biplot analysis showed that there is enough genetic variation among cultivars for germination characteristics associated under drought tolerance. Cultivars Likord and Okapi were identified as the most tolerant genotypes. Result indicated that principal component analysis can be used as a useful technique for screening drought tolerant genotypes and identifying relationships between indices.

The allelopathic effects of leaves at rosette stage of the hoary alyssum (Berteroa incana L.) against some associated grasses like, prairie June grass (Koeleria macrantha), Idaho fescue (Festuca idahoensis), blue-bunch wheatgrass (Pseudoroegneria spicata) and cheat grass (Bromus tectorum) and its own were investigated. The experiment al materials used were the leaf extracts and its allelopathic effects on seed germination and seedling emergence of the abave mentioned grasses in Petri dishes. According to our study, leaves of hoary alyssum rosettes at stage have the potential to reduce germination rate, root and shoot growth of pasture grasses and hoary alyssum itself due to its allelopathic effect. The leaf leachate solution bioassays also showed that the germination of cheat grass was more susceptible to 4% solution of allelopathic extract of leaves. Hoary alyssum leaf extract also exhibited allelopathic self-inhibition, in both seedling root and shoot growth at 2 and 4% concentrations. Self- inhibitory allelopathic effects of hoary alyssum could also be important in preventing seed germination and seedling establishment of neighboring plant.

A factorial experiment with forty one triticale genotypes and two wheat cultivars (‘Kavir’ bread wheat cultivar and ‘Dipper-6’ durum wheat cultivar as salt-tolerant genotypes) as the first factor and six salinity levels of 0, 0.5, 1, 1.5, 2 and 2.5 percent (0, 85, 170, 255, 340 and 425 mM) of NaCl as the second factor was conducted. Results indicated that the increase of salinity level has lead to a significant decrease in germination percentage, number, weight and length of roots and number and weight of shoots of the germinated seeds. There was a high and significant genotypic difference in germination-related traits of seeds. Moreover, interaction of salinity × genotype was highly significant in the mentioned traits. ‘Kavir’ cultivar of bread wheat and ‘Dipper-6’ cultivar of durum wheat were less salt-tolerant compared to triticale genotypes at the germination stage. The Caracal, Prego, ‘Lasko’ and ‘Zorro’ genotypes were least affected by different salinity levels compared to control treatment and hence could be suggested as salt-tolerant triticale genotypes at the germination stage. On the other hand, ‘Pollmer’, ‘Alamos-83’ and ‘Magnat’ genotypes were most affected at different salinity levels compared to control treatment and hence could be suggested as salt-sensitive triticale genotypes at the germination stage for further studies. Overall, salinity stress developed by 170 to 425 Mm NaCl in triticale and the increment of salts lead to a regular decrease of germination and seedling growth variables.

In this study, the relationship between altitude, climate and soil characteristics as important and effective factors on the growth characteristics, seed germination and essential oils of Ziziphora clinopodioides were examined. Three habitats of this species with different altitudes were selected in Alborz and Mazandaran provinces. Growth characteristics of Z. clinopodioides bushes in 45 plots located at the three habitats were recorded. Seed of this species collected from three habitats and their viability was determined. Three soil samples were taken from each habitat and some physical and chemical characteristics were measured. Analysis variance results of data showed that there is a significant difference among the three habitats from the viewpoint of growth characteristics, soil features and common combinations of essential oils. The highest seed viability was obtained for Rineh habitat with chilling and scratching seed coat. The most important environmental factors affecting the vegetative characteristics and essential combinations was determined using principal component analysis. The results showed that annual temperature, absolute minimum temperature, maximum temperature of the warmest month, number of frost days, altitude, electrical conductivity, moisture saturation, organic matter and soil texture had the greatest impact on these properties. [ABSTRACT FROM AUTHOR]

Wild cherry (Prunus avium) is a native fast growing broadleaved tree in Hyrcanean forests producing valuable wood. Prunus seeds have long dormancy and there is variety of methods for breaking dormancy of its seed. This study was conducted in order to overcoming dormancy and germination of Prunus seed. For this purpose, seeds were collected from Aliabad Katool region in forests of Golestsan province, north of Iran. The seeds with mosocarp, without mesocarp and without endocarp were subjected to warm stratification (4 weeks, 20 ˚C) followed by cold stratification (10 weeks, 5 ˚C). Results showed that mesocarp and endocarp had significant effects on overcoming seed dormancy and germination characteristics. Germination percent, germination speed and germination value in seeds stratified without endocarp were greater than those in seeds stratified with mesocarp and without mesocarp. The results revealed that the seeds without endocarp were the most favorable treatment to break dormancy and to improve germination characteristics in Prunus avium seeds.

Effects of provenance and seed moisture content (SMC) on viability, germination and vigor of chestnut-leaved oak(Quercus castaneifolia) acorns were investigated in laboratory. For this purpose, 1500 sound and mature acorns were selected from three different provenances in Loveh forest, north eastern of Iran, located in elevations of 400, 1000 and 1600 meter above sea level, with initial moisture content of 47.0%, 43.0% and 42.8%, respectively. In order to set up 5 different SMC levels (including control, 39.4%, 35.1%, 30.1% and 25.9%) in each seed provenance, acorns were dried for 7 days close to silica gel in 27°C. All dried acorns imbibed in tap water for 24h and incubated under optimum growth condition (8h light in 30°C, and 16h dark in 20°C) for 30 days using a complete randomized factorial design, with 4 replications. At the mentioned period, number of germinant, and characteristics of emerged seedlings were recorded every other day. Results showed that acorn quality decreased with seed MC reduction. So that, in all studied provenances, reduction of SMC lead to reduce seed viability, germination percent, germination speed, germination value, germination energy, and vigor index. Accordingly, it can be said that Q. castaneifolia seed apart from provenance has recalcitrant seed storage behavior. In this study, we found that threshold water content (TWC), critical water content (CWC), and lethal water content (LWC) of chestnut-leaved oak seed are %35.5, %30.1 and %24.3, respectively. Incidentally, aforesaid limits changed slightly in different provenances. Totally, in order to retain chestnut-leaved oak seed quality, the results suggest that seed technologists should retain SMC above %35.5 (TWC). Because in lower SMC, seed viability decreases gradually. So that until CWC (%30.1) half of seeds lost their viability. Furthermore, because rehydration of seeds with SMC bellow %24.3 (LWC) can not restore their viability, silviculturists and forest nursery managers should avoid sowing acorns with SMC bellow %24.0.