Abstract:

In view of nitrate accumulation Chinese chive production, effects of exogenous salicylic acid on nitrate accumulation and reduction and assimilation in the leaves of Chinese chive were studied. The results indicated that the nitrate content of Chinese chives were significantly decreased from 15.9% to 21.6% with various concentration SA treatment after 6 to 9 days under different levels of nitrogen. Optimal concentration of SA is 3.0 mmol·L^-1, and SA concentration reached 10.0 mmol·L^-1, nitrate accumulation could be aggravated. After 9 days with spraying 3.0 mmol·L^-1 SA on leaves, the activity of nitrate reductase (NR) and glutamine synthetase (GS) were increased 48.9% and 40.3%; photosynthetic rate and dissolvable protein were increased 43.4% and 21.3%; However, the activity of GOT and GPT were slightly higher than the control. Therefore, activity of NR (which was named as 'N-reducing-driving-pump') and GS (which was called 'first driving pump') were significantly increased by spraying on leaves with exogenous SA, while photosynthesis and transaminations were played the positive role of coordination, and translation of nitrate into free amino acid and dissolvable protein were promoted and nitrate accumulating into the vacuole of Chinese chives were reduced.

Key words: Chinese chive, salicylic acid, nitrate accumulation, nitrate reduction and assimilation