不同磷水平对雷竹幼苗根系形态、酸性磷酸酶活性的影响

为了解不同磷水平下,雷竹幼苗根系形态和酸性磷酸酶活性的变化,以无性繁殖的雷竹苗作为试验材料,采用砂培试验方法,研究不同磷水平(0,0.5,5,50,500 mg/L)对雷竹幼苗的根系形态、酸性磷酸酶活性的影响.结果表明,随着磷浓度的增加,雷竹幼苗的根冠比呈逐渐降低趋势,添加磷素促进有机物在地上部分的积累,从而降低了根冠比值;0.5 mg/L处理时,根系长度达最大值1344.76 cm/株,根表面积和根体积在0 mg/L处理下均达最大值,分别为384.28 cm2/株和11.67 cm3/株;在0～5 mg/L磷浓度范围内,雷竹幼苗叶片和根尖酸性磷酸酶(Apase)活性随供磷水平的升高而降低,无磷处理时,叶片和根尖Apase活性均达到最大值,分别为14.44 μmol/(g· min)和11.46 μmol/(g· min).这表明雷竹幼苗根系形态的变化和酸性磷酸酶活性的增强,可能都是其对低磷环境的一种适应性反应.

Effects of Phosphorus on Root Morphology and Acid Phosphotase Activity of Phyllostachys praecox

To understand the effect of different phosphorus concentration on root morphology and acid phosphotase activity in Phyllostachys praecox. The effects of phosphorus concentrations, e.g. 0, 0.5, 5, 50, 500 mg/L, on root morphology and acid phosphotase activity of one-year old Phyllostachys praecox were investigated by potted sand experiment. The results showed that with phosphorus concentration increasing, root/shoot ratio of Phyllostachys praecox decreased gradually. Addition of phosphorus to promote on the accumulation of organic matter, thereby dropped the value of root shoot ratio.0.5 mg/L of phosphorus concentration, root length reached a maximum value of 1344.76 cm/plant. Root surface area and root volume reached the maximum as 384.28 cm2/plant and 11.67 cm3/plant respectively in 0 mg/L of treatment. In the range of 0 to 5 mg/L of P concentration, acid phosphotase (Apase) activities in the leaf and root decreased gradually. They were maximum as 14.44 μmol/(g?min) and 11.46μmol/(g?min) respectively, when incubated under 0 mg/L of P concentration. These suggested morphological change and acid phosphatase activity enhancement induced by a P deficiency could be an adaptive response of Phyllostachys praecox to low phosphorus.