Dataset Information

Physiological, biochemical and genetic responses of Caucasian tea (Camellia sinensis (L.) Kuntze) genotypes under cold and frost stress.

ABSTRACT:

Background

Cold and frost are two serious factors limiting the yield of many crops worldwide, including the tea plant (Camellia sinensis (L.) Kuntze). The acclimatization of tea plant from tropical to temperate climate regions resulted in unique germplasm in the North-Western Caucasus with extremely frost-tolerant genotypes.

Methods

The aim of the current research was to evaluate the physiological, biochemical and genetic responses of tolerant and sensitive tea cultivars exposed to cold (0 to +2 °C for 7 days) and frost (-6 to -8 °C for 5 days). Relative water content, cell membranes integrity, pH of the cell sap, water soluble protein, cations, sugars, amino acids were measured under cold and frost. Comparative expression of the following genes ICE1, CBF1, WRKY2, DHN1, DHN2, DHN3, NAC17, NAC26, NAC30, SnRK1.1, SnRK1.2, SnRK1.3, bHLH7, bHLH43, P5CS, LOX1, LOX6, LOX7 were analyzed.

Results

We found elevated protein (by 3-4 times) and cations (potassium, calcium and magnesium) contents in the leaves of both cultivars under cold and frost treatments. Meanwhile, Leu, Met, Val, Thr, Ser were increased under cold and frost, however tolerant cv. Gruzinskii7 showed earlier accumulation of these amino acids. Out of 18 studied genes, 11 were expressed at greater level in the frost- tolerant cultivar comparing with frost-sensitive one: ICE1, CBF1, WRKY2, DHN2, NAC17, NAC26, SnRK1.1, SnRK1.3, bHLH43, P5CS and LOX6. Positive correlations between certain amino acids namely, Met, Thr, Leu and Ser and studied genes were found. Taken together, the revealed cold responses in Caucasian tea cultivars help better understanding of tea tolerance to low temperature stress and role of revealed metabolites need to be further evaluated in different tea genotypes.

SUBMITTER: Samarina LS

PROVIDER: S-EPMC7457925 | biostudies-literature | 2020

REPOSITORIES: biostudies-literature

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Physiological, biochemical and genetic responses of Caucasian tea (<i>Camellia sinensis</i> (L.) Kuntze) genotypes under cold and frost stress.

Samarina Lidiia S LS Malyukova Lyudmila S LS Efremov Alexander M AM Simonyan Taisiya A TA Matskiv Alexandra O AO Koninskaya Natalia G NG Rakhmangulov Ruslan S RS Gvasaliya Maya V MV Malyarovskaya Valentina I VI Ryndin Alexey V AV Orlov Yuriy L YL Tong Wei W Hanke Magda-Viola MV

PeerJ 20200828

<h4>Background</h4>Cold and frost are two serious factors limiting the yield of many crops worldwide, including the tea plant <i>(Camellia sinensis</i> (L.) Kuntze). The acclimatization of tea plant from tropical to temperate climate regions resulted in unique germplasm in the North-Western Caucasus with extremely frost-tolerant genotypes.<h4>Methods</h4>The aim of the current research was to evaluate the physiological, biochemical and genetic responses of tolerant and sensitive tea cultivars ex ...[more]

PMID: 32923182

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