Enhancing Seedling Growth in Capparis spinosa L. Seeds: Effects of Soaking and Cold Stratification

Document Type : Research Paper

Authors

1 Department of Plant Production and Genetics, Faculty of Agriculture, University of Zanjan, Zanjan, Iran

2 Seed and Plant Certification and Registration Institute, Karaj, Iran

3 Department of Plant Production, Universitat De Valencia, Valencia, Spain

Abstract

The caper bush (Capparis spinosa L.), a hardy Mediterranean plant, exhibits remarkable resilience to arid conditions while offering a wealth of medicinal and industrial applications. However, low and inconsistent seed germination has often hindered large-scale cultivation, primarily due to physical and physiological dormancy. This study investigates the effects of various seed soaking durations and stratification times on different germination substrates, specifically sand and paper. Nine caper ecotypes were selected from diverse provinces of Iran. The study included control seeds and evaluated three soaking periods: soaking seeds in tap water at room temperature for 24 hours, 15 days, and 30 days. Additionally, five stratification periods were assessed at 4 °C for 7, 14, 21, 28, and 35 days. The results indicated that cold stratification applied over various periods in a sand substrate was the most effective method for breaking dormancy. Among the ecotypes studied, Alborz exhibited the highest germination percentage (91%) following a 35-day cold stratification period. The treatment demonstrated a positive impact on both the germination percentage and the mean daily germination rate. suggesting that cold stratification is the most effective approach to overcoming seed dormancy in caper ecotypes. Furthermore, our findings revealed that sand is the superior substrate for enhancing caper seed germination. The results imply that the incidence of fungal infection in sterilized sand is lower than in paper, and moisture levels are more uniformly maintained during germination. It was also noted that caper plants derived from freshly collected seed do not consistently develop fully, with only approximately 10% of fresh seeds germinating. The reactions of six caper ecotypes to cold stratification indicate that physiological dormancy is the primary factor contributing to the low germination percentage and rate. Additionally, both physical factors (such as the hard seed coat) and physiological factors (including the immature embryo) contribute to seed dormancy in caper seeds. The seed coat and the mucilage layer that developed its surface represent the primary barriers to germination. The responses of six caper ecotypes to cold stratification further confirm that physiological dormancy plays a significant role in low germination percentages and rates. Consequently, low winter temperatures achieved through cold stratification may be critical in facilitating the spread of caper ecotypes in Iran.

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  1. Kdimy A., El Yadini M., Guaadaoui A., Bourais I., El Hajjaji S., Le H.V. Phytochemistry, biological activities, therapeutic potential, and socio-economic value of the caper bush (Capparis spinosa L.). Chemistry and Biodiversity. 2022; 19: e202200300. https://doi.org/10.1002/cbdv.202200300
  2. Nowruzian A., Aalami A. Effect of different treatments on dormancy breaking for seed germination enhancement and metabolite analysis of Capparis spinosa L. Journal of Medicinal Plants and By-Products. 2023; 12: 387-396. https://doi.org/10.22092/jmpb.2022.357295.1443
  3. Saleh S.S., M Serag El-Din W., Youssef S.M. Enhancement Rutin production from Capparis spinosa plant by UV-C or gamma irradiation using in vitro culture. Egyptian Journal of Horticulture. 2024; 51: 41-59. https://doi.org/10.21608/EJOH.2023.215114.1251
  4. Trovato M., Brini F., Mseddi K., Rhizopoulou S., Jones M.A. A holistic and sustainable approach linked to drought tolerance of Mediterranean crops. Frontiers in Plant Science. 2023; 14: 1167376. https://doi.org/10.3389/fpls.2023.1167376
  5. Zittis G., Almazroui M., Alpert P., Ciais P., Cramer W., Dahdal Y., Fnais M., Francis D., Hadjinicolaou P., Howari F. Climate change and weather extremes in the Eastern Mediterranean and Middle East. Reviews of Geophysics. 2022; 60: e2021RG000762. https://doi.org/10.1029/2021RG000762
  6. Archana B., Bharath P., Deepika G., Kiran M.D., Pavani B. Pharmacological, Pharmacognostic and phytochemical review of Capparis spinosa L. Future Journal of Pharmaceuticals and Health Sciences. 2022; 2: 9-21. https://doi.org/10.26452/fjphs.v2i1.165
  7. Karimzadeh S., Safaie N., Mojerlou S., Ebrahimi L. Two new endophytic Microascus species from Capparis spinosa L. in Iran. Journal of Crop Protection. 2024; 13: 89-99. http://jcp.modares.ac.ir/article-3-72950-en.html
  8. Chedraoui S., Abi-Rizk A., El-Beyrouthy M., Chalak L., Ouaini N., Rajjou L. Capparis spinosa L. in a systematic review: A xerophilous species of multi values and promising potentialities for agrosystems under the threat of global warming. Frontiers in Plant Science. 2017; 8: 1845. https://doi.org/10.3389/fpls.2017.01845
  9. Annaz H., Sane Y., Bitchagno G.T.M., Ben Bakrim W., Drissi B., Mahdi I., El Bouhssini M., Sobeh M. Caper (Capparis spinosa L.): an updated review on its phytochemistry, nutritional value, traditional uses, and therapeutic potential. Frontiers in Pharmacology. 2022; 13: 878749. https://doi.org/10.3389/fphar.2022.878749
  10. Merlino M., Condurso C., Cincotta F., Nalbone L., Ziino G., Verzera A. Essential oil emulsion from caper (Capparis spinosa L.) leaves: Exploration of its antibacterial and antioxidant properties for possible application as a natural food preservative. Antioxidants. 2024; 13: 718. https://doi.org/10.3390/antiox13060718
  11. Foschi M.L., Juan M., Pascual B., Pascual-Seva N. Water uptake and germination of caper (Capparis spinosa L.) seeds. Agronomy. 2020; 10: 838. https://doi.org/10.3390/agronomy10060838
  12. Asaadi A.M. Effects of different treatments on improving seed germination characteristics in medicinal species of Origanum vulgare and Thymus transcaspicus. Journal of Medicinal Plants and By-Products. 2017; 6: 191-200. https://doi.org/10.22092/jmpb.2017.113542
  13. Kumar M., Sarvade S., Kumar R., Kumar A. Pre-Sowing treatments on seeds of forest tree species to overcome the germination problems. Asian Journal of Environment and Ecology. 2024; 23: 1-18. https://doi.org/10.9734/ajee/2024/v23i5543.
  14. Olmez Z., Yahyaoglu Z., Ucler A. Effects of H2SO, KNO, and GA, treatments on germination of caper (Capparis ovata Desf.) seeds. Pakestan Journal of Biological Science. 2004; 7: 879-882. https://doi.org/10.3923/pjbs.2004.879.882
  15. Wang M., Yuan X., Xu L. Preliminary study on bioassay of Capparis spinosa L. seed extract and seed germination. PeerJ. 2023; 11: e15082. https://doi.org/10.7717/peerj.15082
  16. Pascual B., San Bautista A., López-Galarza S., Alagarda J., Maroto J. Germination behaviour after storage of caper seeds. Seed Science and Technology. 2006; 34: 151-159. https://doi.org/10.15258/sst.2006.34.1.16
  17. Abadi N.E.M., Kaboli SH., Rejali F., Zolfaghari A.A. Improvement of germination characteristics of capper (Capparis spinosa) with biological, chemical, and mechanical priming. Journal of Arid Biome. 2021; 10: 149-158. https://doi.org/10.29252/aridbiom.2021.13439.1781
  18. Pascual-Seva N., San Bautista A., López-Galarza S., Maroto J., Pascual B. Effect of accelerated ageing on germination in caper (Capparis spinosa L.) seeds. In V Int Symp on Seed, Transplant and Stand Establishment of Hortic Crops 898. 2009;69-74. https://doi.org/10.17660/ActaHortic.2011.898.7
  19. Foschi M.L., Juan M., Pascual B., Pascual-Seva N. Influence of seed-covering layers on caper seed germination. Plants. 2023; 12: 439. https://doi.org/10.3390/plants12030439
  20. Aghighi Shahverdi M., Omidi H., Tabatabaei S.J. Effect of nutri-priming on germination indices and physiological characteristics of stevia seedling under salinity stress. Journal of Seed Science 2017; 39: 353-362. https://doi.org/10.1590/2317-1545v39n4172539
  21. Gorzi A., Omidi H., Bostani A. Morpho-physiological responses of Stevia (Stevia rebaudiana Bertoni) to various priming treatments under drought stress. Applied Ecology and Environmental Research. 2017; 16:   4753-4771.,  https://doi.org/  10,15666/aeer/1604-47534771
  22. Hunter J.R. Seed dispersal and germination of Enterolobium cyclocarpum (Jacq.) Griseb.(Leguminosae: Mimosoideae): are megafauna necessary. Journal of Biogeography. 1989: 369-378. https://doi.org/10.2307/2845228
  23. Pascual B., San Bautista A., Pascual Seva N., García Molina R., López-Galarza S., Maroto J. Effects of soaking period and gibberellic acid addition on caper seed germination. Seed Science and Technology. 2009; 37: 33-41. https://doi.org/10.15258/sst.2009.37.1.05
  24. Marković M., Grbić M., Skočajić D., Đukić M., Đunisijević-Bojović D. Germination of Capparis spinosa L. seeds under different dormancy breaking treatments. In Proceedings of the X International Scientific Agriculture Symposium Agrosym. 2019; 460-464.
  25. Labbafi M., Mehrafarin A., Badi H., Ghorbani M., Tavakoli M. Improve germination of caper (Capparis spinosa L.) seeds by different induction treatments of seed dormancy breaking. Trakia Journal of Sciences. 2018; 16: 71-74. https://doi.org/10.15547/tjs.2018.01.011
  26. Kaya M., Kulan E., Gümüşçü G., Gümüşçü A. Factors affecting germination performance of four endemic sideritis. Journal of Agricultural Sciences. 2015; 21: 406-413. https://doi.org/10.3390/seeds3030029
  27. Baskin J.M., Baskin C.C. What kind of seed dormancy might palms have? Seed Science Research. 2014; 24: 17-22. https://doi.org/10.1017/S0960258513000342
  28. Song Y., Li X., Zhang M., Xia G., Xiong C. Effect of cold stratification on the temperature range for germination of Pinus koraiensis. Journal of Forestry Research.. 2023; 34: 221-231. https://doi.org/10.1007/s11676-022-01540-y
  29. Caldwell P., Biberand J. Seed germination and seedling survival of Spartina alterniflora Loisel. American Journal of Agricultural and Biological Sciences. 2008; 3: 633-638. https://doi.org/10.3844/ajabssp.2008.633.638
  30. Bhatla S.C., Lal M.A. Seed dormancy and germination. in, Plant Physiology. Development and Metabolism (Springer). 2023. https://doi.org/10.1007/978-981-99-5736-1
  31. Bhattacharya A. Effect of low-temperature stress on germination, growth, and phenology of plants: A review. Physiological Processes in Plants Under Low Temp Stress. 2022: 1-106. https://doi.org/10.1007/978-981-16-9037-2_1
  32. Yang L.E., Peng D.L., Li Z.M., Huang L., Yang J, Sun H. Cold stratification, temperature, light, GA3, and KNO3 effects on seed germination of Primula beesiana from Yunnan, China. Plant Diversity. 2020; 42: 168-173. https://doi.org/10.1016/j.pld.2020.01.003
  33. Al‐Hawija B.N., Partzsch M., Hensen I. Effects of temperature, salinity and cold stratification on seed germination in halophytes. Nordic Journal of Botany. 2012; 30: 627-634. https://doi.org/10.1111/j.1756-1051.2012.01314.x
  34. Karlsson L.M., Tamado T., Milberg P. Inter-species comparison of seed dormancy and germination of six annual Asteraceae weeds in an ecological context. Seed Science Research. 2008; 18: 35-45. https://doi.org/10.1017/S0960258508888496
  35. Cheng J., Huang H., Liu W., Zhou Y., Han W., Wang X., Zhang Y. Unraveling the effects of cold stratification and temperature on the seed germination of invasive Spartina alterniflora across latitude. Frontiers in Plant Science. 2022; 13: 911804. https://doi.org/10.3389/fpls.2022.911804
  36. Feurtado J.A., Yang J., Ambrose S.J., Cutler A.J., Abrams S.R., Kermode A.R. Disrupting abscisic acid homeostasis in western white pine (Pinus monticola Dougl. Ex D. Don) seeds induces dormancy termination and changes in abscisic acid catabolites. Journal of Plant Growth Regulation. 2007; 26: 46-54. https://doi.org/10.1007/s00344-006-0035-4