Iranian Journal of Seed Research

In order to investigate the seed vigor of corn hybrid 704 after maternal plant foliar application with methanol, some micro and macro-nutrients an experiment was conducted in a factorial form based on RCBD with three replications during growing seasons of 2010-2011. Treatments were four growth stages (the 8-10 leaves, the tasseling, the seed-filling, all the stages), seven levels of foliar application (Methanol, Zn, B, Mg, N, Mn, a mixture of all combinations) and control. The analysis of the data showed a significant effect of the combination type of foliar application in different stages on the germination percent, mean daily germination, germination speed, seedling vigor index, radical length, plumule length and seedling dry weight. The detailed results of the study showed that foliar application with N, Mg, Zn, Mn and B in grain-filling stage, foliar application with N, Mg and Mn in tasseling and foliar application with N, Mg and B in all stages had the highest germination percent (100%) and mean daily germination (14.29%). Also, Mg-foliar application in grain-filling and all stages, B-foliar application in grain-filling stage had the highest germination seed (12.33). In addition, Mg-foliar application in grain-filling stage had the vigor index, radical length, plumule length and seedling dry weight.

The effect of seed rate of alfalfa (Medicago sativa L.) and efficiency of plant growth promoting bacteria (PGPR) that facilitates phosphorus uptake with different doses of phosphate fertilizer was evaluated on seed quality. For this purpose, the germination and seed vigor tests before and after accelerated aging were performed in a split split plot experiment based on randomized complete block design with three replications in 2010 in the field of education and research in the College of Agriculture and Natural Resources, Tehran University, Karaj. Phosphorus factor at 4 levels (0, 30, 60 and 90 kg Phosphorus.ha-1) in main plots, PGPR (Pseudomonas) in three levels (no bacteria, bacterial strains, No. 9 and bacterial strains No. 41) in subplots and rate of seed factors on three levels (2, 6, and 10 kg of seed per hectare) were the sub-subplots. The results showed the highest rate of germination and seed vigor obtained by use of 6 kg seeds per hectare, PGPR No.41 strains with 30 kg Phosphorus per hectare and after accelerated aging. The highest rate of germination and seed vigor at 10 kg of seed per hectare were found for PGPR No.41 strains, with 60 kg Phosphorus ha-1 treatments. After accelerated aging practices to achieve maximum germination index and vigor, seed rates and phosphorus requirement were more than standard conditions. Based on obtained results for the storage conditions, bacterial strains No. 41 had a better effect on increasing seed vigor than bacterial strains No. 9. To produce alfalfa seed with high vigor and obtain better results, use of optimum seed rates and phosphorus (6 and 30 kg.ha-1, respectively) along with PGPR (strain No. 41) could be considered in crop plants.

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.

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.

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. 

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%.

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.

In this study, the effect of different doses of gamma radiation was investigated on seed germination factors of Caper species. Gamma irradiation was performed using a cobalt-60 radiation with the radiation speed of 0.018 Gray/second and five doses of gamma radiation (0, 20, 40, 60 and 100 Gray) in a completely randomized design with 4 replication. The results showed that gamma radiation significantly affects some of the seed germination factors. So that the 100 Gray treatment increased the germination percentage up to 43.2% as compared with other treatments. The average time of germination in seeds treated with gamma decreased 0.91 days rather than control. Length of the stem let in gamma treatments increased 62.3% rather than control; so that the fresh and dry weight of stem let at 100 Gray were respectively increased 171.4 and 27.3% in comparison with the control. The fresh and dry weight of rootlets were respectively increased 417.9% and 668% rather than the control one. Seed vigor at 100 Gray was 32.3% higher than the control. From among the different studied doses, 100 Gray showed the highest influence on the seed germination and physiology although the induced changes were in low amounts. This study revealed that gamma irradiation has not major influences on improving seed germination characteristics of Caper shrubs.

Seed priming is a method which is a quite effective method for improving germination and seedling establishment. Two separate experiments were performed to determine the best hydro and osmopriming treatments effects on canola‘s seed germination. The experiments were performed in seed technology laboratory of Islamic Azad University, Karaj, Iran, 2014. The first experiment contained three canola varieties seeds hydropriming (Okapi, Zarfam and Talayeh) using tap water over time interval 0. 2, 6, 10, 14, 18, 20 and 24 hours. The second experiment included, tree canola cultivars in accompany with six concentrations of ZnS04 (0, 0.035, 0.1, 0.4, 1 and 4 gr.Lit^-1) over priming time interval of 0, 6, 10 14 and 18 hours. Both experiments were conducted as a factorial experiment in the context of completely randomized design (CRD) with four replications. The results revealed that the maximum germination percentage across all cultivars e.g. Okapi (99%), Zarfam (95%) and Talayeh (80%) is achieved at 10 hours hydropriming interval. Also concerning to germination rate, the best performance was observed for Talayeh cultivar at 10 hydropriming hour’s interval. The most vigor longitudinal and vigor weighted indices (1050.55 and 4.56) were observed in the Okapi cultivar in the fourth hydropriming level. The interaction between the cultivars, the concentration of ZnS04 and osmopriming time was significant for all characters except for shoot dry weight and vigor weighted Index. The three-way interaction showed that the highest shoots dry weight (0.11, 0.057 and 0.055) and also vigor weighted index observed in Okapi, Zarfam and Talayeh cultivar in 0.035 concentration of ZnS04 (gr.lit^-1) at the time was 10 hours, respectively. The results of this study showed that hydropriming and ZnS04 might improve the performance of rapeseed Cultivars seed.

One of the important strategies for increasing germination speed and germination percentage, to produce high-quality seedling and plant optimal establishment is seed priming. In order to evaluate reactions of a lentil seed to priming duration and concentrations of the applied material as priming, a factorial experiment based on a completely randomized design with three replications was done in the agronomy laboratory of agriculture and Natural Resources College of Gonbad Kavous University in 2013. Factors included priming duration (4, 8 and 12 h) and various concentrations of the priming (hydro priming, hormonal priming by gibberellic acid and salicylic acid with the concentrations of 50, 100 and 150 ppm and non primed seeds). Results showed that the interaction effect of the concentrations and duration of the priming was significant on whole measured traits except the seed vigor index, germination percentage and seedling dry weight at 1% probability level. The lowest duration of germination (5, 10, 90 and 95%) obtained in the hydropriming treatment (2.72, 5.43 and 18.17 hour). The highest radicle fresh weight was observed in hydropriming treatment in three studied durations priming. In this study; the highest rate of germination obtained from GA_50ppm during 12 hours. GA_50ppm increased Germination percentage (98%). The greatest radicle length, shoot length and relative growth rate was obtained in the treatment of the gibberellic acid 100 ppm during 8 hours. All the average, gibberellic acid 100 ppm in 8h had an additive effect on the most of the measured traits of the lentil seed. Therefore, it can be introduced as the best mixture treatment.

Efficient seed germination and rapid and uniform seedling emergence are important in commercial agriculture. Therefore, the use of strategies to improve germination and seedling establishment is necessary for increasing productivity. Hydropriming has been suggested as a simple pre-germination strategy to improve seed performance. In this study, the effects of different durations of hydropriming (10, 24, 48 and 72 hours) at different temperatures (10 and 25 ˚C) compared to unprimed seeds on the vigor and germination performance of five milk thistle accessions (Ahvaz, Sari, Esfahan, Dezfol and Gachsaran) were evaluated. An experiment was conducted as a factorial experiment based on a completely randomized design with three replications. Germination performance was evaluated by final germination percentage, mean daily germination, mean germination time, the coefficient of germination, Timson's index, time to reach 50% the final germination percentage, germination value, coefficient of uniformity of germination, length and dry weight of seedlings and vigor index. The results show that germination capacity, germination rate and seedling vigor indexes increase significantly in hydro primed seeds at a temperature of 10˚C, whereas a decrease in hydro primed seeds at a temperature of 25˚C. Our results also show that the efficacy of hydropriming on seedling emergence and vigor traits depends on the priming duration and temperature. Hydropriming at 10˚C indicated the most effective on germination indicators and seedling vigor when compared to unprimed seeds. In addition, the comparison of germination and growth indicators in different durations of hydropriming in five milk thistle accessions indicated that the best duration of hydropriming for Ahvaz and Gajsaran is 72h, for Sari and Dezfol is 48 and 72h and for Esfahan is 10 and 24h. Therefore, the effect of hydropriming on germination performance and seedling vigor depends on plant association and hydropriming time and therefore, the selection of the best condition for hydropriming will improve the seed germinability and vigor.