Metabolomics analysis reveals the responses of tea plants to excessive calcium

Abstract

BACKGROUND: The proper growth and development of tea plants requires moderately acidic soils and relatively low calcium levels, and excessive calcium at high pH can damage tea plant roots. To reveal the effects of calcium on the responses of tea plant to three pH levels (3.5, 5.0 and 6.5), a repeated test of two factors was designed. RESULTS: Root growth and elemental analysis indicated that excessive calcium improved the growth of tea roots at low pH conditions, whereas it did not harm the growth of tea roots under normal and high pH conditions, especially at pH 6.5. Excessive calcium antagonized the absorption and utilization of magnesium by tea plants. Gas chromatography-mass spectrometry results showed that the addition of Ca 2+ resulted in the primary metabolism in roots being more active at a low pH level. By contrast, it had obvious adverse effects on the accumulation of root metabolites with high calcium treatment at normal or high pH. Differential metabolites identified using ultra-performance liquid chromatography quadrupole time of flight mass spectrometry indicated that flavonoids demonstrated the largest number of changes, and their biosynthesis was partially enriched with excessive calcium at low and high pH conditions, whereas it was down-regulated under normal pH conditions. Kaempferol 3-(2 0 -rhamnosyl-6 0 -acetylgalactoside) 7-rhamnoside, quercetin 3-(6 0 -sinapoylsophorotrioside) and delphinidin 3-(3 0 -p-coumaroylglucoside) showed the greatest increase. The results of gene expression related to root growth and calcium regulation were consistent with root growth and root metabolism. CONCLUSION:The overall results demonstrated that high Ca concentrations further aggravate the detrimental effects of high pH to tea roots. However, it is interesting that excessive calcium reduced the harm of a low pH on tea root growth to some extent.

Metabolomics analysis of the effect of acidification on rhizosphere soil microecosystem of tea tree

“…Soil metabolomics is a large-scale study of low-molecularweight organic compounds in soil, and it provides an important means to reveal complex molecular networks and metabolic pathways in soil microbial communities and to evaluate soil function (Withers et al, 2020). In recent years, many scholars have used soil metabolomics to analyze the effects of environmental factors on soil microbial diversity and soil function, and a series of important research results have been obtained (Brown et al, 2021;Liang et al, 2021;Sun et al, 2022a;Wu et al, 2022). However, few studies have been reported using soil metabolomics to analyze the effects of acidification on microbial diversity and function in tea rhizosphere soil.…”

Analysis of growth resistance mechanisms and causes in tea plants (Camellia sinensis) in high-pH regions of Northern China

“…If the effective Ca content in the soil exceeds 500 mg kg −1 , it is not suitable for tea plant cultivation (19). Under high-pH conditions, excessive Ca treatment was previously shown to cause damage to tea roots (19).…”

Effects of pruning on mineral nutrients and untargeted metabolites in fresh leaves of Camellia sinensis cv. Shuixian

“…Through long diversification processes, tea plants have formed their own ecological adaptation types ( Liang et al., 2021 ). For one, tea adapted to grow in calcium-deficient acidic soil by demanding relatively low amounts of Ca, and thusly is considered a calcifuge plant ( Liang et al., 2021 ).…”

“…Through long diversification processes, tea plants have formed their own ecological adaptation types ( Liang et al., 2021 ). For one, tea adapted to grow in calcium-deficient acidic soil by demanding relatively low amounts of Ca, and thusly is considered a calcifuge plant ( Liang et al., 2021 ). Pruning shortens the transport distance of nutrients, allowing Ca to accumulate in tea leaves where it may promote the accumulation of phenolic glycosides, which is consistent with previous reports that Ca can regulate sugar metabolism in sugar beet ( Hosseini et al., 2019 ).…”