Iranian Journal of Seed Research

Effect of Drought Stress and Normal Irrigation During Flowering to Maturity of 10 Spring Oilseed Rape (Brassica napus) Genotypes Seed Germination

Aidin Hamidi

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.

Effect of Flooding, Acidity and High Temperatures on Seed Germination and Durability of Common Purslane

Shahram Nazari

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.

Effect of Storage Condition, Initial Seed Moisture Content and Germination on Soybean Seed Deterioration

Saman sheidaei

In order to assess seed deterioration of soybean at Ardebil province, this study was conducted as a factorial experiment based on randomized complete block design in 2014. The treatments consisted of germination ability, seed moisture content and seed storing conditions. Germination ability treatment was concluded of three germination levels: 80%, 85% and 90%. Also, three rates of seed moisture content including 10%, 12% and 14%; and two seed storing conditions including seed storage of Moghan and controlled storage were considered as second and third treatments. The results indicated that seed quality significantly reduced by increasing the seed moisture content up to 14% and this moisture content was determined as inappropriate moisture for soybean seed storage. Seeds with high moisture content showed significantly lower normal seedlings percent, germination rate and seedling vigor indices. However, there was no significant difference between 12% and 10% seed moisture contents, so it can be concluded that 12% seed moisture content is proper moisture for soybean seed storage. According to the results, enhancement of seed moisture content more than 12% will result in more accelerated deterioration of soybean seed, in a way that seeds with higher moisture content, especially at inappropriate seed storage conditions will lose their quality and will cause yield reduction at field due to low plant density aroused from inadequate seedling emergence.

Effect of Seed Coat Color and Different Treatments on Seeds Dormancy and Germination Characteristics of Mustard (Sinapis arvensis)

Hamid Sharifi

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.

Effect of Different Treatments on Seed Dormancy Breaking and Germination Stimulation of Ammodendron persicum

Ali Tavili

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.

The Effect of Planting Date and Seed Moisture Content at Harvest on Seed Germination Indices of Corn (Zea mays) Cv. S.c704-Produced in Ardebil Province (Moghan)

Bita Oskouei

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.

Effect of Harvesting Time and Drying Temperature on Soybean Seed Quality

Hossein Sadeghi

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%.

Allelopathic Effect of Yarrow (Achilla wilhelmsii) and Habek Mint (Mentha longifolia) on Seed Germination Indices of Plantain (Plantago major)

Amin Salehi

In recent years the use of allopathic effects on weed management seems to have attracted many professionals. In order to investigate the effect of aqueous extracts of Yarrow (Achilla wilhelmsii L.) and Habek mint (Mentha longifolia (L.) Huds) medicinal plant on germination indices of plantain, two experiments were conducted in completely randomized design with three replications in 2014 in the laboratory of seed technology of Yasouj university. Treatments consisted of 0, 25, 50, 75 and 100% concentrations of aqueous extract of Yarrow and Habek mint aerial parts. The results showed that the extract of Yarrow and Habek mint aerial parts on germination percentage, root and shoot length, root and shoot fresh and dry weight and seed vigor was significant. The maximum percentage and rate of germination have belonged to the control treatment (distilled water) and by decreasing the aqueous extract concentrations of each plant, the percentage and rate of germination increased. The minimum percentage and rate of germination have belonged to 100% concentration of aqueous extract that had no significant difference by 75% concentration. Finally, these results showed allelopathic effects of aqueous extract aerial parts of Yarrow and Habek mint, as a bio-herbicide on growth and germination of plantain.

Germination Model for Arizona Cypress (Cupressus arizonica) in Response to Temperature and Drought Stress

Mehrdad Zarafshar

Select the appropriate tree species and compatible with harsh environmental conditions, with a high survival rate and optimal growth, is very important in the principled forestation projects. Offering moisture - temperature - time seed germination model is one of the solutions to the prediction of seed germination patterns as in this study, germination behavior model in four replications of 50 seeds of Cupressus arizonica (dishes 11cm) on the incubator was examined by applying five levels of water stress (0, -0.5, -1, -1.5, -2 MPa) and temperature treatments (10, 15, 20, 25, 30 °C). The results showed that the optimum temperature (To) and the basic temperature (Tb) for germination is 19.23±0.5 and 6.54 ± 0.0 °C respectively, and amount of the hydro time constant (θ_H) for this species is 0.29±0.11. According to the results, temperature and water potential factors and their interaction affected significantly on time and percent germination. Value of the hydrothermal time model was determined by using θ_HT= [(Ψ-Ψ_{b (g)}) (T-T_b)] tough model that its rate was 126.3 MPa°C. d with 0.87 coefficients of determination.

Effect of Vermicompost Extract on Germination Characteristics of Chickpea (Cicer arietinum) Under Salinity Stress

Rrahele Aahmadpour

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.

Determination of Cardinal Temperatures and Response of Securigera securidaca to Different Temperatures of Germination

Zeinab Alipoor

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 Potential of the Extract From Six Ornamental Spices on Germination and Seedling Growth of Marigold (Calendula officinalis)

Somayeh Rastegar

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.

Effect of Hydropriming and Seed Size on Germination Characteristics and Seedling Growth of Vigna radiata Seeds under Salinity Stress

Ghasem Parmoon

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.

Effects of Hardening and Quality of the Seeds From Different Positions of Inflorescence on the Storability of Pot Marigold

Mohammad Sedghi

Marigold (Calendula officinalis) is a medicinal plant belonging to the Asteraceae family, which seems necessary the review of its various features especially the improvement of reproduction in order to the development of vegetation and extraction of raw pharmaceutics materials. In order to study the effects of seed hardening on the quality of seeds harvested from different positions of inflorescence on the storability of pot marigold, an experiment conducted at the University of Mohaghegh Ardabili in 2011. Seeds hardened before planting with CaCl₂2% and distilled water. At harvest, the seeds collected from both inner and outer regions of the inflorescence from storage experiments in the laboratory. Harvested seeds stored for six months at 40°C. Then an experiment conducted as factorial based on a completely randomizes design with four replications at the laboratory. Results showed that the highest germination percentage (96%), rate (3.91 day^-1), radicle length (5.71 cm) and seed residual dry weight (0.061 g) were related to outer positioned seeds. The highest plumule length (4.79 cm) and seedling dry weight (0.016 g) obtained from outer seeds hardened with distilled water. In conclusion, for best stability results of pot marigold seeds, it is recommended to harden seeds before planting with water and harvest outer seeds from the inflorescence.

Response of Safflower (Carthamus tinctorius) Seed Germination under Cadmium Nitrate Stress to Salicylic Acid Priming

Mohsen Movahhedi Dehnavi

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.