绿斑病藻寄生对夏橙叶片光合作用特性的影响

以盆栽的2年生奥灵达夏橙为试材，研究了绿斑病藻寄生对夏橙叶片光合作用特性的影响.结果表明，轻度病叶对叶绿素总量（Chl a+b）、类胡萝卜素含量（Car）、净光合速率（P_n）、胞间CO₂浓度（C_i）、原初光能转换效率（F_v/F_m）、光合电子传递量子效率（ΦPS Ⅱ）和光化学猝灭系数（qP）无显著影响；中度病叶和重度病叶的Chla+b、Car、P_n、F_v/F_m、ΦPS Ⅱ和qP较对照分别下降了23.85%、26.49%、43.3%、4.5%、35.1%、22.5%和37.61%、44.04%、64.5%、8.6%、63.6%、40.1%，与对照差异显著，而C_i较对照显著上升.绿斑病藻的大量寄生减弱了夏橙叶片的光合作用，而净光合速率的下降主要是由非气孔因素限制引起.

Effects of Apatococcus lobatus parasitization on leaf photosynthesis characteristics of orange (Citrus cv. Olinda)

With 2-year pot-grown grafted Citrus cv. Olinda as test material, this paper studied the effects of Apatococcus lobatus parasitization on its leaf photosynthesis characteristics. No significant differences were observed between slightly affected and control leaves in their total chlorophyll (Chl a + b) and carotenoid (Car) contents, net photosynthetic rate (P(n)), intercellular CO2 concentration (C(i)), primary maximum photochemical efficiency of PS II (F(v)/F(m)), quantum efficiency of noncyclic electron transport of PS II (phiPS II), and photochemical quenching (qP), but for medium and severely affected leaves, their Chl a + b, Car, P(n), F(v)/F(m), phiPS II and qP decreased by 23.85%, 26.49%, 43.3%, 4.5%, 35.1% and 22.5%, and 37.61%, 44.04%, 64.5%, 8.6%, 63.6% and 40.1%, respectively, while C(i) increased, with significant differences to the control. It could be concluded that the massive parasitization of A. lobatus caused a stress to orange plant, and non-stomatal limitation was the dominating factor of P(n) reduction.