Magnesium nutrition on accumulation and transport of amino acids in tea plants

作者：Ruan Jianyun^*; Ma Lifeng; Yang Yajun

来源：Journal of the Science of Food and Agriculture, 2012, 92(7): 1375-1383.

DOI：10.1002/jsfa.4709

• amino acids
• carbohydrate
• internal nitrogen cycling
• magnesium nutrition
• tea
• theanine

BACKGROUND: Free amino acids in young tea shoots are important chemical constituents, remarkably influencing the quality of green teas. Nutrient solution, soil pot and field experiments were conducted to investigate the effect of magnesium nutritional status on accumulation and transport of free amino acids in tea plants (Camellia sinensis (L.) O. Kuntze). RESULTS: A sufficient supply of Mg in nutrient solution increased biomass production and concentrations of free amino acids, notably theanine in young shoots and roots, without affecting total N in the leaves, absorption rates of inorganic N and glutamine synthetase activity. Amino acids in xylem saps and phloem exudates or total sugars in phloem exudates of tea plants from pot and field experiments showed their highest levels in bud breaking and shoot extension in early spring (March and early April). Application ofMg increased the amounts of amino acids and total sugars in the xylem saps and phloem exudates. CONCLUSION: Adequate supply of Mg nutrient promoted the synthesis of theanine in roots and its accumulation in the young shoots of tea plants. Magnesium nutritional status was an important factor influencing the mobility of amino acids and sugars via xylem and phloem especially when N and C reserves remobilized to support spring growth of young shoots.

• 出版日期2012-5
• 单位中国农业科学院