Key Laboratory for Forest Resources Conservation and Utilization in the Southwest Mountains of China, Ministry of Education, Southwest Landscape Architecture Engineering Research Center of State Forestry Administration, Southwest Forestry University, Kunming, 650224, Yunnan, China.
Ecology and Environment Department, Southwest Forestry University, Kunming, 650224, Yunnan, China.
BMC Plant Biol. 2021 Jan 21;21(1):55. doi: 10.1186/s12870-021-02841-w.
Intercropping is often used in the tea producing areas where land resources are not so abundant, and the produced green tea is tasted more delicious through a tea-Chinese chestnut intercropping system according to the experience of indigenous farmers. The length and weight of tea leaf increase under this intercropping system and their root systems are stratified vertically and coordinate symbiosis. However, the delicacy mechanism under the intercropping is not fully understood.
Green tea from the Chinese chestnut-tea intercropping system established in the 1980s ranked highest compared with a pure tea plantation from the same region. Based on the non-targeted metabolomics, 100 differential metabolites were upregulated in the tea leaves from intercropping system relative to monoculture system. Twenty-one amino acids were upregulated and three downregulated in response to the intercropping based on the targeted metabolomics; half of the upregulated amino acids had positive effects on the tea taste. Levels of allantoic acid, sugars, sugar alcohols, and oleic acid were higher and less bitter flavonoids in the intercropping system than those in monoculture system. The upregulated metabolites could promote the quality of tea and its health-beneficial health effects. Flavone and flavonol biosynthesis and phenylalanine metabolism showed the greatest difference. Numerous pathways associated with amino acid metabolism altered, suggesting that the intercropping of Chinese chestnut-tea could greatly influence amino acid metabolism in tea plants.
These results enhance our understanding of the metabolic mechanisms by which tea quality is improved in the Chinese chestnut-tea intercropping system and demonstrate that there is great potential to improve tea quality at the metabolomic level by adopting such an intercropping system.
在土地资源并不丰富的茶叶产区，通常采用间作的方式，根据当地农民的经验，通过茶-板栗间作系统生产的绿茶口感更好。在这种间作系统下，茶叶的长度和重量增加，其根系垂直分层，协调共生。然而，间作的微妙机制尚不完全清楚。
与同一地区的纯茶园相比，80 年代建立的板栗-茶间作系统生产的绿茶排名最高。基于非靶向代谢组学，与单作系统相比，间作系统中的茶叶中有 100 种差异代谢物上调。基于靶向代谢组学，有 21 种氨基酸上调，3 种下调；有一半上调的氨基酸对茶味有积极影响。与单作系统相比，间作系统中的天门冬氨酸、糖、糖醇和油酸含量更高，苦味黄酮类化合物含量更低。上调的代谢物可以促进茶叶的品质和有益健康的功效。类黄酮和黄酮醇生物合成以及苯丙氨酸代谢表现出最大的差异。许多与氨基酸代谢相关的途径发生改变，这表明板栗-茶间作可以极大地影响茶树的氨基酸代谢。
这些结果增强了我们对板栗-茶间作系统改善茶叶品质的代谢机制的理解，并表明通过采用这种间作系统，可以在代谢组学水平上极大地提高茶叶的品质。
