Search published articles


General users only can access the published articles

Sayyed Ali Tabatabaei, Omid Ansari,
Volume 3, Issue 1 ((Spring and Summer) 2016)
Abstract

The objective of this research was to evaluate the effect of salicylic acid and gibberellic acid on germination characteristics and changes of proline, protein and catalase activity of Brassica napus seedlings under Cu(SO4) stress. The experimental design was factorial with complete randomized design as a base design with 3 replications. The first factor was 4 levels of Cu(SO4) stress (0, 10, 20 and 30 mg/l), and the second factor was 4 levels of priming with salicylic acid and gibberellic acid 50 mg/l, hydro prime and control (non-priming). Results showed that with increasing levels of Cu(SO4) stress, germination characteristics (germination percentage, germination rate, normal seedling percentage, seedling length and seed vigor index) reduced and using of salicylic acid, gibberellic acid and hydro prime increased germination characteristics. The highest germination percentage (94%), germination rate (30.75 seed per day), normal seedling percentage (86.17%) seedling length (10.53 cm) and seed vigor index (9.08) were attained from priming by salicylic acid 50 ppm under non-stress conditions. Cu(SO4) stress increased proline (35%) and catalase (37%) activity but reduced protein (65%) and priming increased proline, protein and catalase activity as compared to unprimed under stress and control conditions. In this study, using priming treatment salicylic acid had usually higher germination characteristics and catalase activity, total proteins and proline content in comparison with untreated or control seeds.


Mehdi Shaban, Farshid Ghaderifar, Hamidreza Sadeghipour, Ahad Yamchi,
Volume 3, Issue 2 ((Autumn & Winter) 2017)
Abstract

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.
 


Omid Ansari, Farshid Ghaderifar, Farzad Sharif Zadeh, Ali Moradi,
Volume 3, Issue 2 ((Autumn & Winter) 2017)
Abstract

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 35oC. 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.
 


Mahnaz Aghdasi, Pooyan Mehrabanjoubani, Tahereh Nezamdoost, Fatemeh Tamaskani,
Volume 4, Issue 2 ((Autumn & Winter) 2018)
Abstract

The present study sought to compare the effect of seed priming by hydropriming, ascorbate and calcium chloride (CaCl2) versus different concentrations of silver nanoparticles on two Iranian rice cultivars (Hashemi and Shiroodi) under drought stress. The experimental design, which was factorial, was completely randomized. The first factor was control (without priming), hydro-priming, 20 mg.L-1 calcium chloride, 20 mg.L-1 ascorbates and 20, 40 and 80 mg.L-1 of silver nanoparticles. The second factor was the drought stress, including control, -1.48 and -4.91 bars created by polyethylene glycol 6000 solutions. In plants without drought stress, the time required to reach 50% germination (T50) reduced to 34 and 54 percent under ascorbate and CaCl2 priming in the Hashemi and Shiroodi cultivars, respectively.  In the drought stress condition, ascorbate and hydropriming pretreatments decreased T50 and the time required to reach 90% germination (T90) more than silver nanoparticles, especially in the Shiroodi cultivar. On the other hand, in comparison with other pretreatments, CaCl2 had an important role in increasing the growth factors in all of the drought stress treatments. Although 40 mg.L-1 silver nanoparticles increased the growth factors to some extent, it seems that higher levels of silver nanoparticles cause stress in seeds and therefore decrease the seed germination and growth of seedlings. By decreasing reactive oxygen species, Ascorbate improves the germination and by increasing plasma membrane efficiency, CaCl2 enhances the seedling growth under drought stress.

Highlights:

  1. Silver nanoparticles increased the effect of stress on the seedlings of rice cultivars.
  2. Ascorbate and calcium chloride improved the germination and seedlings growth of the rice cultivars, respectively under drought stress conditions.

Seyed Ali Tabatabaei, Omid Ansari,
Volume 5, Issue 2 ((Autumn & Winter) 2019)
Abstract



Extended abstract
Introduction: Heavy metal pollution is one of the most serious environmental problems. These metals which accumulate in food chain bring about a lot of hazards to both humans and animals. Among heavy metals, lead is considered to be the most dangerous heavy metal in the environment. It contaminates the environment through the lead-acid battery industry, paint and gasoline additives, insecticides, chemical fertilizers, car exhaust pipes and soldering. The objective of this study was to investigate the effect of Pb(NO3)2 on germination characteristics and biochemical changes of two wheat cultivars (Chamran and Kohdasht cultivars).
Materials and Methods: The objective of this research was to evaluate germination and biochemical changes of two wheat cultivars under Pb(NO3)2 stress, using three-parameter sigmoid model. The experimental design adopted was factorial with a completely randomized design, as the base design, with 3 replications. The first factor was 2 wheat cultivars (Kohdasht and Chamran), and the second factor was 6 levels of Pb(NO3)2 (0, 0.25, 0.5, 0.75, 1 and 1.5 mg.L).
Results: The results showed that with increases in levels of Pb(NO3)2 stress, germination percentage, germination rate, normal seedling percentage, seedling length, seedling weight and seed vigor index reduced for both wheat cultivars. The results of fitting three-parameter sigmoidal to characteristics indicated that the highest characteristics and X50 were obtained from the Chamran cultivar. The highest germination percentage (96%), germination rate (23 seeds per day), normal seedling percentage (93.33%), seedling length (13.07 cm), seedling weight (0.07) and seedling vigor index (12.18) were obtained from the Chamran cultivar under non-stress conditions. Pb(NO3)2 stress increased proline and catalase activity but reduced protein, proline and protein for the Chamran cultivar, as compared with the Kohdasht cultivar.
Conclusion: Generally speaking, the results showed that Pb(NO3)2 had a significant effect on germination characteristics and catalase, proline and protein of wheat. Finally, it could be said that in copper-accumulated areas, choosing proper cultivars can slightly mitigate the damages caused by copper. The Chamran cultivar seems to be a better candidate for these conditions.
 
Highlights:

  1. Evaluation of the effect of Pb(NO3)2 stress on germination characteristics of wheat.
  2. Using three-parameter sigmoid model for the evaluation of biochemical changes and germination of wheat under Pb(NO3)2 stress.

Mohsen Malek, Farshid Ghaderi-Far, Benjamin Torabi, Hamid Reza Sadeghipour,
Volume 6, Issue 2 ((Autumn & Winter) 2020)
Abstract



Extended Abstract
Introduction: Priming is one of the most commonly used seed enhancement techniques. Events such as increased synthesis of nucleic acids, activation of repair processes, increased respiratory activity, and improved antioxidant capacity during priming lead to advanced metabolism in seeds. The most important effects of priming include increased percentage, speed and uniformity of germination and emergence. However, the longevity of primed seeds in storage is the major concern for researchers as it restricts widespread use of this technique. Some researchers believe that priming reduces the storage capacity of seeds, while others have reported increased seed shelf life after using priming treatments. Therefore, this study sought to investigate the effects of priming on the storage capacity of the seeds of canola cultivars under different storage conditions.
Material and Methods: In this study, the effects of priming on the shelf life of seeds of three canola cultivars including Dk-xpower, Traper and Hayola50 were investigated. For this purpose, the seeds were first treated with hydropriming and osmopriming methods. Then primed and control seeds with 6, 9, 12 and 15% moisture content were stored for 8 months at 15, 25, 35 and 45 °C. Sampling from different seed treatments was carried out at intervals of 1 to 30 days to assess germination. Finally, by fitting a three-parameter logistic model to cumulative germination data versus the day after storage, the time to germination loss to 50% was calculated and used to compare seed storage behavior between the treatments.
Results: The results showed that the storage behavior of canola seed varies greatly depending on the cultivar, and each cultivar showed a distinct behavior. Priming effects on the shelf life of seeds were different depending on the storage conditions, cultivars and also the priming methods. Comparison of the effects of priming on the seeds’ shelf life under different storage conditions showed that priming treatments were more efficient under higher seed moisture content and storage temperatures than those with lower seed moisture content and storage temperatures. In addition, priming treatments in Dk-xpower cultivar often increased the seeds’ shelf life. However, in the Traper and Hayola 50 cultivars, hydropriming often improved the seeds’ shelf life, and in contrast to osmopriming, it led to a decrease in the shelf life of the seeds.
Conclusion: Based on the results of this study, it was shown that priming effects on canola seed viability can be a function of various factors such as cultivar, storage conditions, and also the type of priming treatment. Moreover, in this study, hydropriming often increased seed longevity whereas osmopriming often increased the deterioration rate and reduced seed longevity.
 
 
Highlights:
  1. Seed storage behavior of canola cultivars was compared under natural storage conditions.
  2. Priming effects on seed longevity of canola cultivars was investigated under different storage conditions.


Page 1 from 1     

© 2024 CC BY-NC 4.0 | Iranian Journal of Seed Research

Designed & Developed by : Yektaweb


This work is licensed under a Creative Commons Attribution 4.0 International License.