The effect of different ammonium and nitrate ratios (NH4+-N : NO3--N = 0:100, 25:75, 50:50 and 75:25) on growth and yield of Chinese kale (Brassica alboglabra Bailey) with 3 cultivars were studied in hydroponics. The results indicated that, compared with the complete nitrate treatment, plant height, stem diameter and biomass of Chinese kale were increased in the low enhancement of ammonium (25%) in nutrient solution, while plant growth and biomass were decreased in the medium (50%) and high (75%) enhancement of ammonium. Ammonium enhancement treatments increased the root/shoot ratio of Chinese kale. Low enhancement of ammonium (25%) in nutrient solution had no significant effect on root activity of Chinese kale, while it was decreased by the medium (50%) and high (75%) enhancement of ammonium treatments. Nutrient solution with 25% ammonium enhancement maintained a high root absorption capacity and increased plant biomass, so it was appropriate to hydroponics for Chinese kale.
