Iranian Journal of Seed Research

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.
 

Gaining insights into the germination and emergence patterns of weeds as well as the factors which have an impact on these patterns is beneficial for weeds management programs. In order to investigate the effect of temperature, waterlogging and salinity on germination and emergence of common lambsquarters, three separate experiments were conducted, adopting a completely randomized design with four replications. The results of the temperature experiment showed that the highest germination percentages, which were 87, 93 and 88%, were obtained in the temperature range of 15, 20 and 25°C, respectively. Maximum values of germination rate, radicle length, plumule length, and seedling dry weight were obtained at 20°C. In addition, optimum seed vigor index of 796.29 was observed at 20°C. The results of the Regression Model showed that germination percentage decreased with an increase in waterlogging duration and halted after 8 and 10 days of consecutive waterlogging. Mean comparisons revealed that radicle and plumule length, seedling dry weight and vigor index decreased significantly by increasing the period of waterlogging. Salinity adversely affected germination percentage, germination rate and seedling dry weight of common lambsquarters. These factors were at their highest amounts in the control and 50 mM NaCl treatments. A downward trend was observed in these factors as NaCl concentrations increased and finally the germination process stopped in concentrations ranging from 300 to 400 mM NaCl. Radicle and plumule length also decreased from 10.51 and 9.23 cm in the control treatment to 3.57 and 2.47 cm at 250 mM NaCl. Overall, the results revealed that the maximum seed vigor index of 851.84 was obtained in the control treatment and seed vigor halted when the salinity level increased to more than 250 mM NaCl. Finally, the results showed that optimum temperature for germination of common lamsquarters was 20 °C and the existence of salinity and waterlogging stress can decrease growth indices of this weed at germination and seedling stages.

The present study sought to evaluate the effect of different temperatures on germination and to determine cardinal temperatures (i.e., base, optimum and maximum) of Secale mountanum at temperatures of 3, 5, 10, 15, 20, 25, 30 and 35^oC. Three nonlinear regression models (i.e., segmented, dent-like and beta) were used for quantifying the response of germination rate to temperature. The results showed that in addition to germination percentage, the temperature has a significant impact on germination rate. Given the root mean square of errors (RMSE) of germination time, the coefficient of determination (R²), the simple linear regression coefficients a and b, and the relationship between the observed and the predicted germination rates, the best models for determination of cardinal temperatures of Secale mountanum were dent-like and beta models. Base, optimum and maximum temperatures were estimated to be about 2.70 to 3.17, 21.27 to 30.00 and 35.00 to 35.05^°C, respectively for the dent-like model. However, given the high value of SE for temperature base and a negative estimate of the base temperature of the beta model, one can report the dent-like model as the right model. Therefore, by using the dent-like model and the estimated parameters, it is possible to use this model for predicting germination.
 

A controlled experiment was run to quantify emergence of Kochia indica under different temperature, salinity and seeding depth levels at Yazd National Salinity Research Center in 2013. Treatments were five day/night temperature regimes: 20/10, 25/15, 30/20, 35/25 and 40/30 °C, five salinity levels: 2, 6, 10, 14 and 18 dS m^-1, and seeding depth on the surface (0 mm), 5, 10 and 15 mm. Final emergence percentage, emergence rate index and elapsed time (days) to reach 50% of the maximum emergence were measured. The results showed that the highest and lowest final emergence percentages were observed at 25/15°C and 40/30°C day/night, respectively. Final emergence percentages at salinity levels of 6, 10, 14 and 18 dS m^-1were, respectively, 9, 22, 36 and 57% lower than 2 dS m^-1. Final emergence percentages for 5, 10 and 15 mm seeding depths were, respectively, 30, 44 and 72% lower, as compared with the placement of seeds on the soil surface. Regression analysis showed that final emergence percentage linearly decreased with increase in salinity and seeding depth levels. However, elapsed time (days) to reach 50% of the maximum emergence (T₅₀), increased as salinity and seeding depth increased, so that the highest T₅₀ was obtained for 18 dS m^-1 and seeding depth of 15 mm. Increase in salinity and seeding depth was associated with a significant decrease in emergence rate index. In addition, using a logistic regression equation, emergence rate of K. indica was quantified on each day after sowing for each temperature-salinity combination to predict the distribution range of the plant in these situations.
 

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.
 

The purpose of this study was to evaluate the effect of Nano TiO₂ and Nano CNT on some germination indices and growth parameters of some hulled barley cultivars. The experiment was conducted in a laboratory at Shahrekord University during 2014. The study was a factorial, adopting a completely randomized design with four replications. Treatments consisted of titanium dioxide nanoparticles and carbon nanotube (CNT) in four concentrations (0, 10, 30 and 60 mg.l^-1) which were applied to seeds of hulled barley cultivars such as Bahman, Makoii and Nosrat. The traits measured were the dry weight of seedling and seedling length, germination percentage, germination rate, mean germination time, the percentage of resistance of radical, seedling vigor length and weight index. The results showed that carbon nanotubes treatments with 60 mg.l^-1 had a significant impact on germination percentage, germination rate, seedling vigor length and weight index and seedling dry weight, as compared with other treatments. In this experiment, the highest percentages of resistance of radicle, seedling vigor weight index and seedling dry weight of Nosrat Cultivar were obtained under 60 mg.l^-1 carbon nanotube treatment, which was 70, 122.2 and 64.9%, respectively, as compared with control treatment. In addition, 60 mg.l^-1 carbon nanotube treatment increased the seedling vigor of Makoii cultivar by 39.8%, as compared with the control treatment. The findings were that in terms of seedling vigor length and weight index, seedling length, seedling dry weight and the percentage of resistance of radical, the Nosrat Cultivar showed better morphological characteristics than Bahman and Makoii cultivars, under laboratory conditions.
 

Asafetida (Ferula assa- foetida L.) is an important medicinal plant belonging to Apiaceae family and has long dormancy. In this research, vernalization, washing time, GA3, medium strength, harvesting time and interaction of these treatments were studied to optimize condition of germination. The results showed that vernalization at 4-5°C for two weeks increased germination by 50%, as compared with the control. Maximum and minimum germinations were obtained for 6 and 2 hours’ washing, which was 42% and 20.47%, respectively. Germination of Ferula was increased (41.5%) by using 10 mg/l of GA3, as compared with the control. In addition, using half strength MS media led to a 25% increase in germination. Moreover, germination mean increased by applying these treatments to one-year-old seeds, in comparison with fresh ones (61% and 36%, respectively). By running factorial experiments in the CRD, the best combination of treatments which could significantly increase germination was a combination of vernalization (4-5°C for two weeks), half strength MS media, GA3 (10 mg/l) and washing time (6h). Given the results of the study, for the purpose of breaking the dormancy of Asafetida, it is suggested that use is made of one-year-old seeds, and half strength MS media, along with right combinations of vernalization, washing time and GA3.
 

In order to study the seed germination behavior and dormancy breaking methods of three weed species (i.e., Chenopodium album, Convolvulus arvensis and Setariaviridis) of pistachio orchards in Rafsanjan, Iran, three separate factorial experiments (with 2 factors) were conducted based on a completely randomized design with four replications, at the Faculty of Agriculture, Vali-E-Asr University of Rafsanjan, Iran, in 2014. Weed seeds were collected from five different regions of Rafsanjan, such as Markazi, Anar, Koshkoiyeh, Kabotarkhan and Nogh. Dormancy breaking treatments for Chenopodium album involved distilled water (control), KNO₃ (at 500 and 1000 ppm), chemical scarification by sulfuric acid (for 5 and 10 min), and cold stratification (for 1, 3 and 5 weeks). Treatments for Convolvulus arvensis involved distilled water (control), scarification by sandpaper, chemical scarification by sulfuric acid (20 and 30 min), and boiling water (for 15 and 30 min). Treatments for Setaria viridis involved distilled water (control), gibberellic acid (250, 500 and 1000 ppm), KNO₃ (500 and 1000 ppm), and cold stratification (for 1, 3 and 5 weeks). The results showed that seed germination percentage (SGP) and mean germination time (MGT) of three weed species were significantly different among weed populations and dormancy breaking methods. For Chenopodium album, cold stratification of 5 weeks resulted in highest SGP (97%) in Nogh population. For Convolvulus arvensis and Setaria viridis, the highest SGP was obtained after scarification by sandpaper (98% in Kabotarkhan population) and using 1000 ppm gibberellic acid (60% in Kabotarkhan population), respectively. In addition, increasing the weight of 1000 seeds in the three weed species in question increased SGP.
 
 

For the purpose of evaluating the effect of chitosan on seed germination and some biochemical characteristics of the milk thistle herb in the conditions of salinity, an experiment was conducted as factorial in a completely randomized design (CRD) with three replications in the Laboratory of Seed Science and Technology of Shahed University, Tehran in 2015. Experimental factors comprised salinity levels (0, 4, 8 and 12 dS.m^-1) and different levels of Chitosan (0, 0.25, 0.5, 0.75 and 1 percent). The results showed that salt stress reduced germination percentage, germination coefficient, germination speed, weight and length vigor index, radical, plumule and seedling length and total biomass and increased mean germination time. Seed priming with chitosan up to 0.5% concentration increased germination coefficient, weighted index vigor and plumule length. The highest amounts of total chlorophyll and total protein were obtained in seed priming with 0.5% chitosan levels in zero salinity level (control). By increasing salinity levels, the activity level of catalase and peroxidase increased, so that the highest level of the activity of these two enzymes was obtained in the salinity level of 12 dS.m^-1 in pre-treatment with 0.5% Chitosan. The results showed that seed priming with chitosan of 0.5% could reduce harmful effects of salt stress on some traits of milk thistle seedlings and could even improve their growth.
 

In order to investigate the effect of pretreatment of chitosan biological compounds on seeds of soybean (Glycine max L. cv. Williams) under salt stress conditions, a factorial experiment was conducted, adopting a completely randomized design with three replications at Shahed University in 2015. Factors examined included the combination of chitosan at three levels (0, 0.25 and 0.5 the weight-volume) and salinity at 4 levels (0, 5, 5.7 and 10 dS/m). The results showed that the interaction of chitosan and salinity had a significant impact on seed germination characteristics such as germination percentage, germination rate, mean germination time, normal seedling and physiological characteristics such as proline and soluble sugars of shoots. In contrast to salt stress increase of 30%, and an increase of 24 and 35% of proline and soluble sugars of the shoot, pretreatment of chitosan (0.25%) improves seedling germination characteristics of soybeans. Given the impact of the treatments of chitosan on seed germination and seedling growth of soybean, it is possible to introduce 0.25% W/V chitosan as a treatment to deal with conditions of salinity.
 

1.  The role of maternal sesame plant (cv. Darab 1) foliar application by zinc and boron elements in germination, vigour and storage capability of seeds was studied.
2. The effect of seeds soaked in solutions enriched with zinc and boron elements on germination, vigour and storage capability of seeds was examined.

1.  Due to higher storage capacity, the use of large seeds brings about increases in the seedling germination rate and their establishment in the field
2. The use of large seeds with more seed vigor decreases competition between seedlings and reduces vapor from the field.

1. For the first time, an augment design was adopted in an experimental study to investigate the non-repeat genotypes in the generations.
2. The tolerance and sensitivity of genotypes were evaluated, consistent with the definition of statistical intervals.
3. The results of this research led to the introduction of superior crossings for replications at the farm level.

1. The germination response of six hybrids of the maze to seed deterioration was investigated.
2. The role of antioxidant enzymes in deteriorated seeds of maize hybrids was examined.

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.