Correlation between Amino Acids Content of Fresh Tea Leaves and Nutrients in Soil

  Objective  Correlation between soil nutrients and amino acids content of fresh tea leaves in autumn was analyzed to optimize the cultivation.

  Method  Based on the projected importance of variables, indices on soil nutrients that significantly affect the amino acids in fresh tea leaves were used in a partial least squares regression analysis to establish linear programming equations. A scheme to optimize the amino acids synthesis and accumulation in tea leaves through soil management was formulated using LINGGO software.

  Result  Correlations between the amino acids in fresh tea leaves and the nutrients in the cultivation soil were obtained. The optimal soil pH for amino acids accumulation in tea leaves was in the range of 4.39 and 4.85, the organic matters at 31.91g·kg⁻¹ (that for taurine and glycine, 34.6 g·kg⁻¹), the total phosphorus 0.44–0.52 g·kg⁻¹, the total potassium at 20.01 g·kg⁻¹, the total nitrogen 1.73–2.13 g·kg⁻¹, the available phosphorus 178.27–219.77 mg·kg⁻¹, the available potassium 180.38–196.54 mg·kg⁻¹, and the available nitrogen 73.22–143.48 mg·kg⁻¹.

  Conclusion  Different soil nutrients affected the composition of tea leave amino acids differently. A plantation managed to use organic fertilizer, mitigate acidification, and apply ample nutrients, especially available nitrogen, in the cultivation soil could significantly increase the amino acids content in tea leaves harvested in autumn.