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Effect of calcium nutrient on calcium distribution and ultrastructure of cell and chloroplast in Bunching Onion (Allium fistulosum L. var. caespitosum Makino) leaf was studied in sands with 4 Ca2+ treatments (0, 40, 80 and 160 mg/L ), in which the solution was Hoagland's. Localization and distribution of calcSuperscript textium and the influence of calcium nutrition on cell ultrastructure were observed by transmission electron microscopy combined with in situ precipitation of calcium with potassium pyroantimonate technique. The results showed that Ca2+ were mainly located in cell membrane, vacuoles, envelope of chloroplast and intercellular space in normal cells of bunching onion, however, Ca2+ was found to compartment in cytosol in large quantity, and the release of membrane-associated Ca2+ to cytosol and wall-associated Ca2+ to the intercellular spaces was observed in Ca-deficient leaves. In serious Ca-deficient leaves, Ca2+ quantities in cell decreased. Under Ca-deficiency, chloroplast membranes, plasma membranes and nuclear membranes were damaged, and cell walls disassociated, an enlarged space could be found between cells. In serious Ca-deficient leaves, cell compartmentation was destroyed, chloroplast deformed, plasma separated from cell wall, then whole cell constricted.

A substrate culture experiment was conducted to study the effect of different biological organic fertilizer levels (control: zero fertilization, low level, medium level and high level) on plant growth and yield of Chinese kale (Brassica alboglabra Bailey). Results showed that compared with control, treatments of medium and high fertilization increased the leaf number, plant height, stem diameter, yield and plant dry matter of Chinese kale. Thus they promoted plant growth. The fertilizer utilization ratio of Chinese kale was the lowest for low fertilization treatment, and it was the highest for medium fertilization treatment, while it was decreased for high fertilization treatment. The treatment of medium level fertilization (30g/plant) promoted plant growth and increased the yield of Chinese kale; also it had the highest fertilizer use efficiency. So it was the appropriate organic fertilization amount for Chinese kale production.

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.

The effect of water stress on growth and quality of bunching onion（Allium fistulosum L. var. caespitosum Makino）was studied in hydroponics by PEG treatments (10%, 15%, 20%). The results showed that the growth of bunching onion was significantly affected by water stress induced by PEG. Plant height, pseudo-stem weight, total plant weight decreased with PEG concentration increased, the inhibitions in 10% PEG and 20% PEG were greater than in 15% PEG. The root/shoot ratio increased in PEG treatments. Concentrations of allicin and pyruvic acid significantly increased at 10, 17 days after PEG treatments. With PEG concentration increased, concentrations of soluble protein increased.

Effect of nitrogen level (50, 100, 200, 300, 400 mg/L) on pigment accumulation of flower stalk in Chinese kale (Brassica alboglabraBailley) (cv. Zhonghua) were studied by hydroponics. The results showed that chlorophyll concentration of flower stalk in 50 mg/L and 100 mg/L N treatments were higher before stage Ⅲ, those in 50 mg/L were the highest, while those in 200 mg/L N treatment were the highest at stage Ⅳ and Ⅴ. Carotenoid concentrations in 50mg/L N treatment were the highest during flower stalk development (except at stageⅤ), while those in 100mg/L N treatment were the highest at stagesⅤ.The concentrations of flavonoids and anthocyanin in flower stalk epidermis were the highest in 100 mg/L N treatment, those in 50mg/L N treatment were higher than other treatments. The ratio of anthocyanin/chlorophyll in flower stalk epidermis also were the highest in 100 mg/L N treatment, and higher in 50mg/L N treatment, thus the epidermis appeared mauve in 50 and 100mg/L N treatments.

Effect of ammonium and nitrate ratios (0:100, 25:75, 50:50 and 75:25) on nutritional quality of flowering Chinese cabbage (Brassica campestris L. ssp. chinensis var. utilis Tsen et Lee) with 3 cultivars were studied in hydroponics. The results indicated that, with the increasing of ammonium proportion in nutrient solution, the soluble sugar content in product organ of flowering Chinese cabbage increased gradually, but Vc content decreased gradually. Enhancement of ammonium by 25% or 50% in nutrient solution increased the soluble protein content in leaf significantly, while it increased gradually in stalk with the increasing of ammonium proportion. Free amino acids in product organ of flowering Chinese cabbage were improved significantly by enhancement of ammonium in nutrient solution. Integrated nutritional quality of flowering Chinese cabbage in 25% ammonium enhancement treatment was better than others under hydroponics condition.