Iranian Journal of Seed 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%.

Germination is the first and the most stages for sainfoin (Onobrychis viciifolia) growth; which it has especially sensitivity to environmental stresses such as alkalinity. The current study was conducted to evaluate the effectiveness of seed pre-treatment methods on improving sainfoin tolerance to alkali stress in germination, early growth and its recovery as a factorial experiment based on a completely randomized design in College of Agriculture, Shiraz University in 2013. The first factor was four seed pre-treatment methods (seed with the pod, seed without the pod, pre-chilling of seed without pod and hydro-priming of seed without pod) and the second factor was five alkali stress levels (pH= 6.7, 7.9, 8.9, 9.8 and 10.7). Alkali stress levels were prepared using two neutral salts (Na₂SO₄ and NaCl) and two alkaline salts (NaHCO₃ and Na₂CO₃). The results showed that germination percentage was decreased as alkalinity (pH) levels were enhanced; so that, there were no germinated seeds in 9.8 and 10.7 treatments. Alkali stress reduced initial germination percentage (51.9%), final germination percentage (51.8%), plumule length (55.7%) and radicle length (72.2%). Under all alkalinity conditions, the lowest seed germination and seedling growth were observed in with pod seed, followed by pre-chilling treatments; while their highest were achieved in without pod seeds and hydro-priming treatments. The highest recovery was observed in without the pod, followed by hydro-primed seeds. Recovery was observed in Pre-chilled and with pod speeds up to 7.9 and in hydro-primed and without pod speeds up to 8.9.

There have been a few studies on removing the seed pods in annual medics, despite its importance. To investigate the role of pod removal on seed germination, seedling growth and antioxidant enzyme activities in annual medic (Medicago scutellata L.) Under salt stress, a factorial experiment was conducted based on a completely randomized design with four replications in 2014. Salinity at 5 levels: 0.62 (tap water as a control), 3, 6, 9 and 12 dS m^-1 was applied using sodium chloride. The results showed that salt stress caused changes in the characteristics of germination, seedling growth and antioxidant enzyme activities. With increasing in salinity levels, rate and percentage of germination as well as root length, shoot length and seedling weight was significantly decreased. However, increasing salinity levels increased the activity of antioxidant enzymes. Germination and growth in seed without pod was greater than those in seeds with pod; however, there were no significant differences between antioxidant enzyme activity; except about ascorbic peroxide that was significantly higher in seed without a pod. In general, salinity reduced germination and growth and increased antioxidant enzyme activity of annual medics. The results showed that planting seeds without pod had advantages for better germination and growth, especially under saline conditions.

In order to study the effect of zinc and magnesium on agronomic and seed germination traits of wheat (Sivand cultivar), the current study was carried out at Mahidasht Agricultural Research Station in Kermanshah over the years 2012 and 2013. The experiment was conducted as factorial based on completely randomized block design with three replications. The treatments consisted of four levels of zinc sulfate (zero, 20, 40 and 60 kg per hectare) and four levels of magnesium (zero, 70, 140 and 210 kg per hectare in the form of magnesium sulfate). The measured parameters included thousand seed weight, hectoliter weight, protein, zinc and magnesium seeds, germination test, growth rate, seed vigor, plant characteristics and grain yield. The results showed the effects of zinc and magnesium factors were significant for most traits at 1 and 5%. The effect of zinc sulfate showed that 60 kg zinc sulfate had the best effect on the traits under investigation. The effect of this treatment on two important traits (i.e., yield and grain protein percent) with 7.10 tons per hectare and 12.05% was higher (about 115 and 103%, respectively), as compared with the control treatment. Effect of magnesium sulfate levels on the traits showed that the treatment of 210 kg per hectare of magnesium sulfate was the superior treatment. The effects of the above-mentioned treatment on yield (7.84 tons per hectare) and grain protein (11.89 percent) were higher than the control treatment, which was 124 and 101.5%, respectively. Given the number of field nutrients and the wheat needs for these elements, the treatments of 20 kg per ha of zinc sulfate and 140 kg per ha of magnesium sulfate were better than other treatments and economically speaking, are very cost-effective and are thus recommended.
 

This study was conducted to evaluate the effects of accelerated aging and natural storage on seed germination and seedling heterotrophic growth of chickpea in Gorgan University of Agricultural Sciences and Natural Resources in 2014. The experiment was carried out, adopting a completely randomized design with four replications. Treatments were 8 aging levels (i.e., 2 years, and 4 years natural storage; 1, 2, 3, 4, 5 days of accelerated aging and a control). The results showed that the effect of aging treatment on all the traits was significant. Reduction of germination percentage, germination rate, root and shoot length seed vigor index and seedling dry weight of 4 and 5 accelerated aging days was higher than 2 and 4 natural storage years. The electrical conductivity of seed lots increased by an increase in accelerated aging to 4 and 5 days, which was higher than 2 and 4 natural storage years. This is due to incapability of a membrane to keep its permeability, which is the result of the higher sensitivity of seeds to accelerated aging. Reduction of the rate and efficiency of reserves used and also dynamic reserves in natural storage was lower than 4 and 5 accelerated aging days. However, maximum rate and efficiency of reserves used and also dynamic reserves were obtained at 2 accelerated aging days. This could be due to increase in repair reaction rates under these conditions and activation of hydrolytic enzymes in seeds. Finally, the results of the present study revealed that damages to chickpea seed at 4 and 5 accelerated aging days are more than 2 and 4 natural storage years, which leads to the reduction of germination percentage and rate.
 

To study the effect of production region and seed size on germination indices and heterotrophic growth components of peanut seedling, a study was performed in three peanut fields in Astaneh Ashrafieh and Agronomy Laboratory of Rasht Islamic Azad University from 2010 to 2012. This research was carried out using the standard germination, cold and accelerated aging tests. Tests were performed using factorial experiment with a completely randomized block design in 3 replications. The first factor was seed production region in 3 levels (Noghredeh, Amshal and Bandar-Kiyashahr) and the second factor was seed weight in 3 levels [large, medium and small]. The results indicated that the effect of production region on the germination speed (p<0.01) and coefficient of uniformity of germination (p<0.05) was significant so that the maximum means (6.17 and 18.11 day^-1, respectively) were achieved in seeds produced in Amshal. The effect of the interaction of the region and seed size on the mean germination speed was significant so that the maximum mean (282.22) was achieved in large seeds produced in Amshal. The effect of production region on the seed reserve use rate was significant in standard germination (p<0.01) and cold tests (p<0.05). The effect of seed size on the seed reserve use rate and seed use reserve fraction were significant (P<0.01) in all the three germination tests. The maximum amount of seed reserve use rate was achieved in seeds produced in the Amshal region (in standard and cold tests with averages of 0.562 and 0.440, respectively). In addition, the maximum amount of seed reserve use rate was achieved in large seeds (with averages of 0.541, 0.470 and 0.277 mg per seed in standard, cold and aging tests, respectively). The maximum seed use reserve fraction was achieved in small seeds (with averages of 1.371, 1.310 and 1.664 in standard, cold and aging tests, respectively).

 

Highlights:

1. Peanut seed germination tests were performed based on seed production regions and seed sizes.
2. Three different vigour tests (standard, aging, cold) were used to identify higher quality seeds.
3. Germination indices indicated high quality in large seeds produced in different environmental conditions.
4. Large seeds had the maximum seed reserve use rate and minimum seed use reserve fraction at the germination stage of peanuts.

This study was conducted to study the effects of different priming methods on germination rate and percentage under salinity stress and to determine the stability of primed seeds. In order to accomplish this, three different experiments were conducted separately, including the experiment of water uptake, the experiment of salinity stress, and the experiment of storability of primed seeds. Priming treatments were five levels of control (unprimed), hydropriming (Hyd), priming with humic acid (HA), priming with salicylic acid (SA) and priming with gibberellic acid (GA). Salinity stresses were four levels of 0, 4, 8 and 12 ds/m of NaCl. The stability of prime seeds was investigated over a period of 226 days after priming. The results of water uptake showed that rapeseeds entered into the third phase of water uptake after 18 hours of hydration. The results of the salinity experiment showed that salinity levels of 12 and 0 ds/m had the lowest (74.3 %) and highest (83 %) germination percentage, respectively. In terms of germination rate, there were significant differences between GA (0.034 h^-1), HA (0.036 h^-1) and Hyd (0.036 h^-1) with C (0.019 h^-1) and SA (0.027 h^-1). Generally speaking, primed seeds germinated better than control seeds at all levels of salinity. The storability of primed seeds and control seeds had no significant decrease during storage. Finally, it was concluded that seed priming increased the tolerance to salinity stress; in terms of storability, there was no significant difference between primed seeds and primed seeds could be stored in the same way as control seeds.

Highlights:

1. At the current research, the stability of prime seeds was investigated for the first time.
2. There was no significant difference between the storability of primed seeds and control (unprimed) at each sampling time (with an exception for SA).
3. Primed seeds had better germination performance than control at the all salinity stress levels.
4. Seed priming treatments using gibberellic acid, humic acid and hydropriming were the best compared with the other treatments.

1. Introduction of proper storage conditions and initial seed moisture in order to decrease fungal damage and soybean seed deterioration.
2. Determination of different fungal damages during the storage of soybean seeds.
3. Determination of relationship between the degree of soybean seed infection of storage fungi and the seed’s quality, its amount of protein and soluble sugars.

1. Using the time to the event model in estimation of seed germination parameters.
2. Comparing the time to event and nonlinear regression methods in different seed germination experiments.
3. Using the Monte-Carlo method for investigating the accuracy of results of the used methods.

1. The effect of priming on the germination and vigor of safflower seeds before and after artificial deterioration was compared and investigated.
2. The effect of priming before and after artificial deterioration on the improvement of safflower seed quality varied in different cultivars.