Iranian Journal of Seed Research

In order to study, the effects of hydropriming and osmopriming on germination characteristics of Nigella sativa L. under salt stress an experiment was conducted in factorial laid out in completely randomized design with four replications at Research Laboratory, Faculty of Agriculture, Mashhad Branch, Islamic Azad University-Mashhad Iran, in 2014. Factors were included of priming treatment in six levels [control (Non-priming), hydropriming with distilled water, osmopriming with KNO3, KCl, CaCl2 and NaCl] and salinity treatment in four levels [0, 50, 100 and 150 Mmol]. Analysis of variance showed that the effects of salinity and seed priming on all measured indices and interaction between two factors on germination percentage and rate, radicle and plumule length and seed vigor were significant at the probability level of 1%. The results showed that with increasing salt concentration all measured traits were decreased. This decreasing started from the 50 Mmol concentration. Under salt stress condition, osmopriming with KNO3 and then hydropriming and osmopriming with KCl improved all germination indices compared with control.

Germination rate and percentage are maximal at optimum temperatures and then reach to zero at the base and ceiling temperatures. An experiment was conducted at the Gonbad Kavous University laboratory as a completely randomized design with 4 replications, to study germination response to temperature and evaluation of cardinal temperature on germination rate and percentage of hibiscus tea. Seeds germinated at 0 to 45 ⁰C by 5 ⁰C intervals. Results indicated that the response of germination percentage and rate adequately fitted with dent like and segmented functions, continually. Base and ceiling temperatures were 1.66 and 43.33 ⁰C for germination percentage and 4.53 and 42.95 ⁰C for germination rate. Optimum temperatures were 30 ⁰C for germination rate and 11.56 and 33.63 ⁰C for germination percentage. In conclusion, base and favorable temperatures for hibiscus tea seeds were 11 and 35 ⁰C. Therefore it is recommended to cultivate at Gonbad kavous weather condition.

The effect of spermidine on seed germination of three different cucumber cultivars under cold stress was studied as a 4×2 factorial experiment by using a completely randomized design with 4 replications. The first factor was 4 concentrations of spermidine consisted of 0 (control), 0.1, 0.5 and 1 mM and the second one was three cucumber cultivars consisted of ‘Emperator’, ‘Amiran’ and ‘Rashid’. For this purpose, 50 seeds of each cultivar were placed on filter papers inside sterilized Petry dishes and spermidine solutions were added to them according to each treatment. All petry dishes were placed at a 13°C temperature of the incubator until end of the experiment and germinated seeds were counted daily. The measured traits were the percentage of germination, plumule length, radicle length, the dry and fresh weight of the plumule and radicle. The results showed that treating seeds of ‘Rashid’ cultivar with 0.1 mM spermidine increased the percentage of germination, plumule and radicle length, fresh and dry weights of radical compared with control. Treating ‘Rashid’ seeds with high concentration (1 mM) of spermidine showed inhibitory effects on all measured characteristics, but in ‘Amiran’ cultivar only decreased the percentage of germination, plumule and radicle length, the fresh and dry weight of radicle.

Due to the importance of medicinal plants, understanding the seed germination response to temperature is agronomically important. A laboratory study was conducted to investigate the effect of different temperatures on seed germination of fennel, cannabis and sesame in a completely randomized design with four replications. Various constant temperatures (5, 10, 15, 20, 25, 30, 35 and 40°C) were considered. According to the results, the effect of temperature on germination rate and percentage in all species was significant. The seeds of fennel were not germinated in 5, 35 and 40 ⁰C and seeds of sesame germinated only in 5 ⁰C. The maximum rate of germination obtained in 30 °C for fennel and 25 °C for sesame and cannabis. The highest germination percentage of fennel and cannabis and sesame were in 20, 25 and 30 0C respectively. The lowest of germination uniformity (GU) were observed in 20 ⁰C for fennel and in 15 ⁰C for cannabis and sesame. Amount of seedling vigor maximized for fennel and cannabis in 25⁰C and for sesame in the 300C. The values of length and weight of radical and plumule were enhanced with the increase of temperature and record on maximum in special temperature and then reduced slowly. The quantitative information provided by this study can be used in prediction of emergence under diverse temperature conditions. Germination of cannabis seeds occurred in a wide range of temperatures and this seed are less sensitive to temperature compared to the other two plants. Germination of fennel seeds was less, except at 200C. The sesame seeds had good germination at 15-35 ⁰C.

In order to study the effect of alkaline stress on seed germination and seedling biochemical characteristics of two safflower cultivars, a laboratory experiment was conducted based on a completely randomized design with three replications in the Vali-e-Asr University of Rafsanjan. Experimental factors included the levels of alkaline with sodium bicarbonate (0, 10, 20, 30, 40, 50 and 60 mM) and two cultivars of safflower (Soffeh and 411). The result showed that alkaline stress had significant effects on seed germination characteristics. Increasing alkaline stress reduced percentage and rate of germination, length and dry weights of shoots and roots, K+ concentration and K+/Na+. However, alkaline increased malondialdehyde content, proline, total carbohydrate and Na+ concentration. In alkaline stress condition, there was a significant difference between cultivars in length of shoots and roots, proline content and K+ concentration. 411 cultivar showed notable superiority compared to Soffeh cultivar. Both cultivars had the highest malondialdehyde at 60 mM alkalinity and the lowest malondialdehyde obtained in Soffeh cultivar and control. The result of this research showed that 411 cultivar was better than Soffeh cultivar in proline and soluble sugar content, but these two cultivars had no significant differences in other traits.

Rapid germination is an important factor determining the final yield. This study was performed to investigate the effects of different levels of methanol and drought stress on germination characteristics of lentil seedlings. The experiment was conducted in completely randomized design with three replications in summer 2014 at the Khatam Alanbia University of Behbahan. The first factor was different levels of methanol equal to 0 (control), 5, 10 and 15 volumetric percentage (v/v), and the second factor we negative water potential in four levels 0, -3, -6 and -9 bar by PEG. Results showed that there was a significant difference between different methanol concentrations regarding germination percentage, germination speed index, plumule and radical length, plumule and radical dry weight, radical area, radical diameter and consumed endosperm (P 0.01). Different levels of methanol caused a significant decrease in germination characteristics compared with to control. Drought stress with -9 bar level significantly decreased germination percentage, germination speed index, plumule and radical length, plumule and radical dry weight, radical area, radical diameter and consumed endosperm compared to other levels. Effects of drought and methanol were significant differences regarding the germination speed index, plumule length, plumule dry weight and consumed endosperm (P 0.05).

In order to investigate the effect of an electromagnetic field and ultrasonic waves on the seed germination of Cuminum cyminum that two separate experiments using a completely randomized design with four replications was conducted at Seed Science and Technology Laboratory of Faculty Agricultural Sciences, the Shahed University of Tehran in 2012. In the first experiment, for the seeds of zero, 10 and 30 min exposure to electromagnetic field intensity was 88 microTesla. In the second test (ultrasonic waves), seeds for zero, 2, 4, 6, 8 and 10 min exposure ultrasonic waves’ intensity were 40 and 59 kHz. The interaction between the electromagnetic field and the length had a significant effect on the traits of length, fresh weight and dry weight of root and shoot, length and weight of root to shoot ratio, percent and rate germination and mean germination time. In most of the studied traits showed that electromagnetic field causes a significant decrease in the number of traits so that the control (zero M.T) had the highest value. The interaction of Ultrasonic waves at the time had a significant effect of on the most traits. Maximum germination percentage (100%) for the treatment of 40 kHz with duration of 4 and 6 minutes and mean germination time was highest in control (10.76 days) and 59 kHz treatment duration of 2 and 4 min (respectively 11.01 and 10.75 days). Generally, Cuminum cyminum seeds responded positively to the use of ultrasonic waves (In contrast field) and germination index was significantly increased in this case.

In order to evaluate the effect of priming on some germination and seedling growth characteristics of safflower (Carthamus tinctorius L.) under drought stress, an experiment was conducted base on completely randomized design with four replications at the Seed Technology Laboratory of Yasouj University, in 2011. Treatments were included of five priming levels (control or no prime, hydro priming, potassium nitrate 3% (KNO3), PEG and Urea -4 bar) as the first factor and three levels of drought stress (0, -4 and -8 bar) as the second factor. The results showed that the interactions of drought stress and seed priming on germination percentage and the germination rate was not significant. But the main impact of priming and drought stress on them was so significant at 1% probability. The highest germination percentage and germination rate (75.66% and 3.62 seed.day-1, respectively) were shown in urea priming and the lowest (52% and 2.31 seed.day-1 respectively) in the control treatment (no prime). Drought stress was caused a significant decrease in germination traits. In general, the results obtained in this study showed that treatment with urea and potassium nitrate compared with PEG improved germination and seedling growth of safflower.

Seeds of seven species of medicinal plants collected from the natural habitat in Lorestan province in summer 2011. Germination test carried out in a completely randomized design with four replications of 25 seeds in H2O. Species of Smyrnium cordifrolium, Kelussia odoratissima, Dorema aucheri and Ferulago angulata had no germination while Heracleum persicum, Bunium luristanicum and Falcaria vulgaris showed germination of 30, 96 and 97% respectively. Different treatments of breaking dormancy applied to the species with germination below 30% [moist-chilling for periods of 2, 4, 6, 8, 10 and 12 weeks, with two concentrations of 250 and 500 ppm of gibberellic acid, a combination treatment (gibberellic 250 ppm + 4 weeks moist-chilling and gibberellic acid 500 ppm + moist-chilling for 4 weeks) and potassium nitrate 2 g/l]. The results showed that moist-chilling was the most effective treatments to break seed dormancy of Heracleum persicum (6 weeks), Dorema aucheri (12 weeks), Kelussia odoratissima (12 weeks) and Ferulago angulata (12 weeks). Therefore, based on their reactions to the treatments, dormancy of Kelussia odoratissima and Ferulago angulata could be classified as deep physiological dormancy and species of Dorema aucheri and Heracleum persicum intermediate physiological dormancy type.

To evaluate the interaction of Cd and SA on seed germination of Safflower (Carthamus tinctorius L. cv. Soffe), this experiment was carried out as a factorial based on CRD with four replications in 2012, in Yasouj University seed lab. Factors included of four levels of seed priming with SA (0, 0.3, 0.6, and 0.9 mM) and eight levels of cadmium nitrate (0, 5, 10, 15, 20, 25, 30 and 35 mM). In all Cd treatments, SA 0.9 mM had maximum germination percentage (84% in 0 mM Cd) and rate (6.58 seed day^-1 in 5 mM Cd), radical length (4.21 cm in 0 mM Cd) and stem (3.29 cm in 0 mM Cd), radical dry mater (2.25 mg in 0 mM Cd), shoot dry matter (0.94 mg in 0 mM Cd) and seed vigor index (6.30 in 0 mM Cd). Generally, seed priming with SA decreased the impact of Cd on seed germination and SA 0.9 mM was the best treatment.

In order to study of drought stress and normal irrigation effect on seed germination and seedling vigor of 10 oilseed rape spring genotypes, RGS003, Sarigol, Option 500, RGS006, 19_H, ORS3150-3006, ORS3150-3008, RG4403, RG405/03 and RGAS0324, an experiment was conducted as factorial, based on a completely randomized design with four replications, in the seed analysis laboratory of Seed and Plant Certification and Registration Institution at Karaj during 2013. Results indicated that RG4403 genotype by 3.498 gr. and RGS006 genotype by 3.082 gr had the highest and lowest one thousand seeds weight respectively. Seeds of Sarigol, Option500 and RGS006 genotype, respectively, by normal irrigation and drought stress, had the most primary root, shoot and seedling length and seeds of ORS3150-3008 and RGAS0324 genotypes by normal irrigation respectively had the most primary root and seedling and primary shoot and seedling dry weight. Seeds of Sarigol and RGAS0324 genotypes by normal irrigation had the highest final germination percent. The highest mean germination time, the coefficient of the velocity of germination and mean daily germination, also respectively belonged to seeds of RGS003genotype by drought stress and19-H and RGAS0324 genotypes by normal irrigation. Besides, Sarigol and RGAS0324 had the most length and weight vigor indices. Generally, results showed that drought stress at flowering and maturity duration caused a decrease in seed quality of studied genotypes, but under what conditions, some genotypes like RGS006, 19-H and ORS3150-3006 seed had relatively optimum germination quality and seedling vigor traits.

This study was performed to investigate interactions of different levels of vermicompost extract and salinity stress on germination characteristics of chickpea seedlings. The factorial experiment was conducted in completely randomized design with three replications. Concentrations of vermicompost extract (0, 5, 10 and 20 volumetric percentage) and salinity levels (0, 30, 60 and 90 mM NaCl). Results showed that there were significant differences (P‌ 0.01) between vermicompost extract and salinity levels regarding germination percentage, radicle length, and shoot dry weight. Salinity stress with 90 (Mm NaCl) level significantly decreased all of the traits compared to the non-stress condition. Effects of vermicompost extract and salinity stress were significant differences (P‌ 0.05) on the germination rate index, radicle length, radicle dry weight and consumed endosperm. vermicompost extract at concentrations of 5 volumetric percentage in moderate salinity stress (30 mM NaCl) and non-salinity stress caused a significant increase (P‌ 0.01) in radicle length, radicle dry weigh and consumed endosperm compared to control.

In order to determinate the cardinal temperatures and investigate the effect of temperature on seed germination and seedling growth of Securigera securidaca, a study was conducted in a completely randomized design with 8 temperature treatments (5, 10, 15, 20, 25, 30, 35 and 40^oC) and four replications in research laboratory of faculty of agriculture at the Birjand University in 2013. A two-segmented linear regression model was fitted between germination rate and temperatures to determine cardinal temperatures for germination. Cardinal (minimum, optimum and maximum) temperatures of germination were determined as -1, 22.5 and 40.2^oC respectively. Maximum rate and percentage of germination obtained in the range of 20-25^oC. Maximum of radicle length and dry weight, maximum of caulicle length and dry weight and maximum of vigor seedling were obtained in 20^oC,10-20^oC and 5-30^oC respectively. Maximum and minimum germination uniformity (GU) was obtained in 25 and 5^oC. 

Allelopathic compounds display an important role in biodiversity, stability and ability of ecosystem production. An experiment was conducted to investigate the allelopathic effect of six species, Cordia myxa, Melia indica, Delonix regai, Terminalia catappa, Eucalyptus camadulensis, Ficus religiosa on germination and seedling growth of Calendula officinalis. An experiment was performed in a completely randomized design with three replications in the lab of the horticultural Hormozgan university during 2014. A completely randomized design with three replications was carried out in the laboratory. Results indicated that the percentage of germination, seed germination rate, plumule and radicle length, and seed vigor of Calendula officinalis significantly reduced under aqueous extract of all species. But, there was no significant difference between dry weights. Delonix regia extract ceased the seed germinates in both concentrations. After that Melia indica extract had a highly significant inhibitory effect on seed germination, plumule and radicle length when compared to control. The results of this experiment also showed that the inhibitory effects of Cordia myxa and Terminalia catappa were lower in compared to other species. Between two concentrations, 100% concentration has a more inhibitory effect. The results of the present study revealed that inhibition of germination and growth parameters of Calendula officinalis showed variation according to the different plants. Cultivation of Calendula officinalis with Melia indica, Delonix regia species don’t suggest in the landscape.

Seed coat color as a perfect and simple index is effective in water absorption, seed dormancy and germination. The mustard plant produces seeds with different coat color. So, in order to investigate the effect of seed coat color on germination rate, the percentage of germination and dormancy of Mustard (Sinapis arvensis L.) seeds an experiment was carried out based on a completely randomized design with four replications. Treatments were included two types of seed coat color (brown and black) and dormancy breaking treatments (Control, Potassium nitrate 0.2%, GA₃ 250, GA₃ 500 ppm and one, two and three weeks prechilling). The results showed that the differences between germination indices traits in brown and black seeds were significant. So that, the germination rate and germination percent in black seed were greater than brown seeds, but the duration of dormancy in brown seeds was greater than black seed. One week prechilling treatment had the most effect on breaking dormancy. So that germination percentage and germination rate for black seed was 75% and 0.54 respectively and these amounts for brown seeds were 58% and 0/43 respectively. Potassium nitrate and GA₃ (250 and 500 ppm) reduced germination rate and germination percent in both types of seeds. In addition, water absorption percent in brown seeds was more than black seeds. The final results showed that heteromorphic seeds of Mustard have variation in duration of dormancy, germination and water absorption percent.

In order to evaluate the effect of hydropriming on seed germination of Vigna radiata under salinity stress, an experiment was arranged in a factorial based on a completely randomized design with three replications in the laboratory of the Agricultural College of the University of Ramin Khuzestan. Treatments were salinity stress at 4 levels (0, 3, 6 and 9 Mmhos) and hydro priming at 3 levels (1, 1.5 and 3 h) and two sizes of seed (small and large seeds) that was carried out by NaCl. Results showed that all of the germination characteristics decreased with increased salinity, but this decrement for seeds that primed at a long time, was less. Also at all characteristics, small seeds, showed better reactions than large seeds. Generally, hydropriming was improved germination characteristics of Vigna radiata under saline conditions. According to this experiment, hydropriming improved germination and establishment.

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.

In order to evaluate the effect of seed moisture content at harvesting time and drying temperature on soybean seed germination characteristics, an experiment was conducted as factorial (2×3×2) based on Randomized Complete Block Design with three replications in Karaj and Moghan areas. The first factor was cultivar with two levels (Williams and L₁₇), the second factor was seed moisture content with three levels (15, 20 and 25%) and the third factor was drying temperature with two levels (30 and 45 °C). Results show that the germination percentage of producing seeds in Karaj (81.3%) were higher than Moghan area (77.4%). The difference between the germination percentage of dried seeds at 30 and 45^◦C with initial seed moisture content of 15% was about 5.5%, while this difference for seeds with 25% initial moisture content was about 18.5%. There was no significant difference between seedling vigor index of seeds with 15% moisture content of two cultivars that have been produced in Karaj, but at 20% moisture content, the seedling vigor index in Williams cultivar (139.7) was higher than L₁₇ cultivar (107.3). The highest (51.42 µsm cm^-1 g^-1) electrical conductivity of seed leakage soluble was obtained from the L₁₇ cultivar with 25% moisture content and 45^◦C and the lowest (28.46 42 µsm cm^-1 g^-1) rate of it was observed in Williams cultivar with 20% moisture content and 30^◦C. According to these results, we must harvest and dry soybean seeds at 30^◦C when its moisture content reached under 20%.

This experiment was conducted as a factorial experiment based on a completely randomized design with three replications at two locations: Agricultural and natural resource center of Ardebil province (Moghan) and seed and plant certification and registration institute of Karaj in 2013. The treatments included: planting date in three levels (10-May, 25-May and 9-Jun), seed moisture content at harvest time in four levels (30%, 25, 20 and 15) and seed size in three levels (flat, round and medium). The measured traits were a standard germination test, mean time of germination, seedling weight and length vigor index, germination percent in radical emergence test and germination percent in cold test. The results illustrated that delayed planting caused reduction of seed quality and this reduction was more obvious in delayed harvest (15%), also the reduction rate in round seeds was more than flattered and medium seeds. The minimum percentage of germination and vigor were seen in round seeds of third planting date and moisture harvest by 15%. So it is recommended for corn seed production to sow the seeds before the last week of May and when seed moisture content reached 30 percent, cob harvesting should be started and the harvest not is delayed.

Three separate experiments conducted to survey the response of two populations of common purslane weed collected from Karaj and Ahvaz on germination and early growth. The first experiment was based on 4 levels of flooding, including 1, 2, 4, 8 days plus non-flooding treatment as a control. Second experiment addressed the impact of various acidity levels, such as 4, 5, 6, 7, 8, 9, 10 and finally third experiment considered the influence of high temperatures of 60, 80, 100, 120, 140, 160, 180, 200, 220 centigrade on germination rate, germination percentage, radicle length and plumule length as well as fresh weight of the aforementioned population of common purslane (Karaj and Ahvaz). Analysis of variance revealed that in both weed populations, all germination indices were impressed by flooding periods, acidity levels and high temperatures. Extending the flooding periods resulted in reducing all measured parameters in both weed populations, so the growth of common people was completely inhibited less than 8 consecutive days of flooding. Germination rate and percentage improved gradually by increasing the acidity value from 4 up to 7. An adverse relation was observed between the measured parameters and temperature variations in both Karaj and Ahvaz weed population. Germination rate and percentage, radicle and plumule length, as well as the fresh weight of seedling, decreased significantly in response to increasing the oven temperature. Overall, it can be concluded that boosting our knowledge about both ecology and biology aspects of the common person can pave the way for introducing new ways in line with expanding long-term strategies, improving management systems and predicting the mode of germination and growth of this important weed.