Iranian Journal of Seed Research

Extended abstract
Introduction: Small size of Satureja (Satureja hortensis L.) seed causes many problems in mechanized cultivation and its seed consumption is increased significantly.  The approach discussed in the present study is the seed coating of Satureja by several matters and selecting the suitable method as well as investigation of adding hormonal and nutritional substances to the selected coating material for better emergence and the elimination of problem arise as a result of coating.
Materials and Methods: Purified Satureja seeds (97%) were prepared and poured into the coating machine at a specified amount. First, 1% solution of benomyl fungicide was sprayed on the seeds. Then some coating powder was sprayed on the spinning wet seeds inside the machine. Then some of the adhesive solution was sprayed on it and again the coating powder was added and this was repeated several times to create a suitable form for the coated seeds. This was repeated using different materials and among these coatings powder, vermiculite and perlite provided better coating on Satureja seed. Then, different materials including gibberellin, BAP, cytokinin, thiourea (CH₄N₂S) and potassium nitrate (KNO₃), phosphorus from H₂PO₄ source and manganese sulfate (MnSO₄) were used to the emergence of the enlarged seeds and also, the emergence of these seeds were evaluated in the greenhouse.
Results: Initial results showed that vermiculite and perlite provided better cover for Satureja compared with the other coating materials. Investigating the emergence of perlite-coated seeds in the greenhouse showed that gibberellin (all concentrations) and kinetin (500 mg/l) present in the seed coat improved the Satureja seed emergence under greenhouse condition. Also, it was found that Thiourea (700 and 7000 mg/l), potassium nitrate (7, 70, 700 mg/l), phosphorous (9 kg/100 kg seed) and manganese sulphate (2 and 4 mg/l) present in the coat significantly increased the Satureja seed emergence and led to improved seedling growth.
Conclusion: Perlite for the purpose of seed pelleting of Satureja showed good results and the use of gibberellin (at all concentrations) and quintine (500 mg/l) in the seed pelleting improved germination of pelleted Satureja seed.
 

Highlights:
1- Technical knowledge of Satureja seed pelleting was obtained.
2- The suitable material to improve the emergence of pelleted Satureja seed was introduced.

Extended Abstract
Introduction: Galbanum is one of the most important native medicinal plants in Iran, and nowadays the use of its products and derivatives has become widespread in various industries. Thus, the excessive harvest of this species within its natural habitats has increased. Therefore, the species is enlisted as prone to extinction. Due to the lack of information about germination behavior and dormancy alleviating or breaking methods of Galbanum seeds, less attention has been paid to this plant species by seed science researchers. Hence, this study was designed and performed to investigate the effects of different treatments on Galbanum seed dormancy-breaking.
Materials and Methods: In this study, two Galbanum seed populations were collected from Boyer-Ahmad pastures (Iran, Kohgiluyeh and Boyer-Ahmad Province) and Pakan Bazr Isfahan Company (Iran). Seeds were exposed to a cold stratification test for 120 days and germinability and dormancy breaking responses were studied. Also, seed drying effects on germinability after exposure to stratification treatment were investigated to evaluate the practical aspects of this treatment. The impacts of different hormonal pre-treatments including gibberellic acid (GA₃) and cytokines (Kinetin, 6-Benzylaminopurine) at different concentrations on germination and dormancy behaviors were investigated so as to assess the effect of these treatments on seed dormancy breaking.
Results: Results showed that germination/dormancy behaviors of Galbanum populations were different and also the effect of different treatments on seeds germination and dormancy varied. An increase in germination was observed when stratification was applied for up to 60 days on two seed populations, thereafter germination decreased by prolonged stratification. Also, it was revealed that desiccation of the treated seeds after stratification reduced seed germination. Examining the cause of this issue revealed that the most important reason for the decrease in seed germination in long periods of stratification was the germination of seeds in the stratification bed and in other words, the difference in seed dormancy levels in different stratification periods. Seed germination behavior and dormancy breaking were improved significantly in both Galbanum populations when the different concentration of gibberellic acid and cytokinins was used.
Conclusion: The results of this study indicated the existence of different levels of seed dormancy in different Galbanum populations. It was also found that cold stratification and hormonal pre-treatment of seeds can be significantly effective in seed dormancy breaking. Eventually, it was concluded that Galbanum seed dormancy was classified as semi-deep and deep morphological dormancy due to the effects of different treatments.

Highlights: