A hydroponics cultivation experiment was conducted using celery,to find the variety of the nitrates auumulated,at different developmental stages,different organ tissues and different harvest.

• 以美国西芹为材料，用营养液盆栽方法，研究了不同生育期、不同部位、不同收获期芹菜体内硝酸盐含量的变化规律．结果表明：芹菜体内硝酸盐的积累量与不同生育期生长势呈正相关；