Use of biochemical compounds in tea germplasm characterization and its implications in tea breeding in Sri Lanka

Abstract

Thirty five tea germplasm accessions selected to represent the germpalsm collection of Sri Lanka was used for biochemical characterization based on the biochemical compounds present in the fresh tea leaf. Rate of fermentation, crude fibre content, total polyphenols, total catechins, chlorophyll- a , chlorophyll- b and total carotenoids were analysed. Principal component analysis (PCA) using 7 biochemical parameters and clustering on first three principal components accounted for 87 % of the total variation and delineated the 35 accessions into 4 clusters. Biochemical parameters such as fermentation rate, total polyphenols, total catechins and plant pigments in green leaf were important in explaining the biochemical variation. The selected 35 accessions could also be categorized into 4 groups based on the fermentation rate. Estate selections (PK2, N2, DUN7, S106, DT1, TC9, WT26 and NAY3) and some introductions (TRI777, INTRI6 and VHMOR) recorded the highest total polyphenols and catechin content. Besides, ASM4/10, TRI2016, TRI2025 and TRI2043 showed the highest content of chlorophylls and total carotenoids. The significant variation of the selected biochemical compounds detected in the present study indicated the high genetic diversity of tea germplasm in Sri Lanka. Results suggests that accessions PLLG2, VHMOR, DUN7 and WT26 possess unique characteristics such as rapid fermentation, high amount of polyphenols and catechins, and these could be used as potential parents for future tea breeding programmes after analyzing other complementary traits. The present study provides useful guidelines on the use of fresh leaf biochemical parameters such as the rate of fermentation, total polyphenols, total catechins, chlorophylls and carotenoid content in characterizing the Sri Lankan tea germplasm. J.Natn.Sci.Foundation Sri Lanka 2013 41 (4): 309-318 DOI: http://dx.doi.org/10.4038/jnsfsr.v41i4.6252