Morphological evaluation of regenerated plantlets of the medicinal plant Jujube ‎‎(Ziziphus jujuba Mill.) with emphasis on somaclonal variation

Jujube (Ziziphus jujuba Mill.) is a medicinally and agriculturally significant fruit tree with a long history of cultivation. In vitro propagation techniques offer an alternative to traditional vegetative propagation, often leading to genetic and phenotypic changes known as somaclonal variation. This study aimed to investigate the impact of long-term in vitro subculturing on the morphological traits of regenerated Jujube plantlets. Single-node explants from three cultivars, Taghab, Siojan and Shahzileh, were cultured on Murashige and Skoog (۱۹۶۲) (MS) medium supplemented with different concentrations of benzylaminopurine (BA) and indole-۳-butyric acid (IBA). The three Jujube cultivars showed the most marked increase in the mean number of shoots when grown on MS medium with amounts of BA (۲ mgL-۱) and IBA (۰.۲ mgL-۱). With regards to morphological traits, the Shahzileh cultivar demonstrated the greatest branching among all cultivars, suggesting superior regenerative capabilities. Several morphological features were evaluated under five subcultures of the Shahzileh cultivar. The Shahzileh cultivar showed the highest branching in the third subculture, and longer shoot length was also recorded at the fifth subculture. With each subsequent subculture, there was a gradual decrease in leaf and node number per branch, suggesting that somaclonal variation may be occurring in these cultivars through regeneration in plantlets. In this study, ۱۰-year-old Shahzileh Jujube trees were used for explants. Only one tree was used as a source of explants, so variations observed in the regenerated plantlets were likely due to several factors, particularly the explant source. The single nodes from the Shahzileh Jujube cultivar were used as explants, which contain meristematic tissues. The use of meristematic tissues such as axillary buds exhibits the chances of somaclonal variation. Plantlets regenerated from nodes of Jujube showed optimal results with ۰.۲ mgL-۱ IBA and ۲ mgL-۱ BA. The combination of auxins and cytokinins has been shown to play a key role in causing somaclonal variation. The volatile chemical compounds present in fruit extracts of three jujube cultivars were identified using Gas Chromatography-Mass Spectrometry (GC-MS). This indicates that the chemical composition of jujube fruits varies significantly among different cultivars. This study investigates the correlation between phenotypic variation induced by in vitro plantlet regeneration across different cultivars and the nutritional quality as well as bioactive compound profiles of their fruits. The outcomes of this research provide valuable insights for cultivar improvement, genetic resource conservation, and the enhancement of production strategies for economically and medicinally important plants such as jujube (Ziziphus jujuba Mill.).

کلیدواژه ها:

Fruit ، In vitro culture ، GC-MS analysis ، Jujube ، Regeneration ، Somaclonal variation ، Fruit ، In vitro culture ، GC-MS analysis ، Jujube ، Regeneration ، Somaclonal variation