Variation in leaf morphology and architecture, phytochemical content, and antioxidant capacity among 36 Camellia sinensis clones of the Indian sub-Himalayan region

Abstract

Camellia sinensis, renowned as the second most widely consumed nonalcoholic beverage worldwide, bears substantial economic importance, prompting cultivators to breed various clones for enhanced flavor and quality. This study analyzed the variation in leaf phenotype, phytochemicals (total tannins and proanthocyanidins content) and antioxidant potential of 36 widely cultivated tea clones from India’s sub-Himalayan region using multivariate analysis. Results indicated that TV23 had the largest leaf and SS27 and RR had the smallest. TS520 was the richest in tannin, proanthocyanidins, and antioxidants, while S3A1 and Heeleakah were the least. Principal components analysis (PCA) and cluster analysis unveiled four morphological clusters (representative clones - TV1, TV23, TV30, 124.48.8) and four phytochemical clusters (representative clones - TS520, TV9, TV27, P126). GC-MS analysis revealed that TV1 and TV30 had high caffeine content (82.0%), while TS520 exhibited abundant antioxidant compounds, including sycllo-inositol (23.84%) and epigallocatechin (4.23%). TS520’s exceptional antioxidant properties, confirmed by DPPH, ABTS, and total antioxidant capacity assays, may result from its cultivation through seed propagation. Correlation analysis showed antioxidant potential had moderate negative associations with leaf size, strong negative with inter-secondary vein number, and positive with petiole length. This study is pivotal for assessing tea clone diversity, with broader applications in tea improvement and breeding programs.

Keywords:

• Leaf architecture
• GC-MS
• Principal Component Analysis
• antioxidant
• tea tannins
• proanthocyanidins

Acknowledgements

PD thanks CSIR-UGC for providing senior research fellowship. ACR acknowledges DBT for SRF. The authors acknowledge the GC-MS facility, AIRF, Jawaharlal Nehru University, New Delhi, and the tea garden managers’ and workers’ assistance during the field visit. We would like to thank our mentors and anonymous reviewers for their constructive comments and help in improving the quality of the manuscript. No funding was provided for this study.

Author contributions

PD: conceptualization, sampling, methodology, investigation, resources, data curation, writing – original draft, writing – review & editing, validation, formal analysis, visualization, software; ACR: investigation, conceptualization, formal analysis, validation, writing and editing, software. IG: resources, acquisition, validation. CG: conceptualization, resources, sampling, writing – review & editing, validation, supervision, project administration, funding acquisition

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

All data generated or analyzed during this study are included in this manuscript.