Evaluation of some secondary metabolites, morphophysiological and biochemical characteristics of Calendula officinalis L. under the influence of chitosan elicitor in in vitro culture

Document Type : Research Paper

Authors

1 Assistant Professor, Department of Horticultural Science and Engineering, Faculty of Agriculture and Natural Resources, University of Hormozgan, Bandar Abbas, Iran.

2 Department of Horticultural Science and Engineering, Faculty of Agriculture and Natural Resources, University of Hormozgan, Bandar Abbas, Iran

3 Department of Horticultural Science and Engineering, Faculty of Agriculture and Natural Resources, University of Hormozgan, Bandar Abbas, Ira

10.22103/jab.2025.24064.1618

Abstract

Objective: Due to its important medicinal metabolites (including calenduloside, quercetin, and others), Calendula officinalis L. is considered an excellent source for new drugs. One of the biotechnological tools for enhancing the production of these metabolites is the use of the elicitation process in vitro culture. Therefore, the aim of this study was to improve the medicinal metabolites, morphophysiological characteristics, and biochemical properties of this plant under the influence of chitosan elicitor in vitro culture.
Materials and methods: In this study, the effects of different seed sterilization methods and seed coating on the germination rate and seed contamination of Calendula officinalis L. were evaluated. A factorial experiment was conducted in a completely randomized design with two factors (sterilization method and seed coating type) and four replications. Then, Low molecular weight chitosan elicitor was prepared in different concentrations (0, 25, 50, and 75 mg/L) and applied to the seeds. Finally, the effects of chitosan on the improvement of morphophysiological, metabolite, and biochemical traits of Calendula officinalis L. in vitro culture were investigated.
Results: The results of the interaction effect between sterilization method and seed coating showed that treatment S2C1 (second sterilization method, place in 10% benomyl fungicide for 5 minutes, place in 70% ethanol for 30 seconds, place in 1% sodium hypochlorite for 15 minutes, combined with no seed coating) had the highest germination percentage (100) compared to other treatments. The results of simple main effect analysis of sterilization methods showed that the highest and lowest contamination rates were related to the first (S1) and third (S3) sterilization methods, respectively. The results of the mean comparison indicated a significant increase in the traits of plant height, fresh weight of seedlings, number and length of roots, stem length, and leaf number and width in all chitosan concentrations compared to the control. The highest and lowest amounts of flavonoids, total phenol, antioxidant activity, anthocyanin, carotenoids, chlorophyll a and b, catalase, peroxidase, and proline content were found in the treatment with 50 mg/l chitosan and the control, respectively. The highest and lowest levels of malondialdehyde were observed in the control and 50 mg/l chitosan treatments.
Conclusion: Overall, the results showed that a chitosan concentration of 50 mg/l was more effective in improving the morphophysiological, metabolic, and biochemical traits of Calendula officinalis L. in vitro culture.

Keywords

References

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Agricultural Biotechnology Journal
Volume 17, Issue 2
May 2025
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