Phytochemical analysis of mite‐infested tea leaves of Darjeeling Hills, India

Abstract

Introduction Darjeeling tea of India is one of the most famous beverages globally. However, a large amount of tea crop is damaged every year by the attack of mites. Objectives The study aimed to determine the changes in different pigments and biochemical components of tea leaves due to mite infestation. Materials and Methods We used UV‐visible and Fourier‐transform infrared (FTIR) spectroscopy simultaneously to understand the damages in pigment contents of the leaves of tea (Camellia sinensis (L.) Kuntze) due to attack of phytophagus mite, Oligonychus coffeae Nietner. Furthermore, chemical analysis of infested tea leaves was also performed to compare the nutrients of the plants, namely total phenol, protein and soluble sugar. Results The UV‐visible study reveals severe reduction of the pigments such as chlorophyll (Chl), carotenoids and xanthophylls in the tea leaf due to mite infestation. The findings of the FTIR study, also shows variation in different physiochemical components in the leaf Chl. The sugar and protein content of the infested leaves have been reduced compared to uninfested ones. Results in the case of tea leaves plucked during first (March) and third (November) flushes show similar trends. Conclusion The increase in phenolic and alcoholic components and decrease in Chl contents may affect the quality of Darjeeling tea. The extent of damages done by the pests measured here could aid the pest management in tea gardens.

Identification of Pu'er raw tea with different storage years by infrared spectroscopy

“…The peak near 1518 cm −1 is the vibration of aromatic ring (Guo et al, 2016). The peaks near 1452 and 1369 cm −1 are due to bending vibration of C-H (Moskal et al, 2018), and the peak near 1238 cm −1 is the vibration of phenolic substance C-O (Banerjee et al, 2019). The peak near 1147 cm −1 is the asymmetric stretching vibration of an ether bond (C-O-C) of the pyranose ring (Paradkar & Irudayaraj, 2006).…”

Acaricidal activity of nishinda (Vitex negundo) leaf and garlic (Allium sativum) bulb extract against red spider mite, Oligonychus coffeae (Acari: Tetranychidae) in tea plantations of Darjeeling hill, West Bengal, India

“…More than one thousand arthropods have been recorded to feed on different parts of the tea plants (Chen and Chen 1989) all over the world. Among them, Oligonychus coffeae Nietner, the tea red spider mite, a major arthropod pest that attacks most cultivars in tea plantations of Darjeeling, India (Das 1965;Banerjee et al 2020) played a significant role for causing damage to tea. The red spider mite increased within a short period of time in the tea plantations due to its high reproductive capacity (Das 1959a(Das ,1959b(Das , 1960.…”