高频度模拟酸雨胁迫条件下菲白竹的光合响应  

Response of photosynthetic characteristics of Pleioblastus fortunei to high frequent simulated acid rain

作　　者：何亚飞[1] 张珊珊[1] 孙鑫[1] 王涛[1] 代丽[1] 谢寅峰[1] 

机构地区：[1]南方现代林业协同创新中心,南京林业大学生物与环境学院,江苏南京210037

出　　处：《南京林业大学学报（自然科学版）》2016年第4期49-55,共7页Journal of Nanjing Forestry University：Natural Sciences Edition

基　　金：“十二五”国家科技支撑计划(2015BAD04B02);江苏高校优势学科建设工程资助项目(PAPD)

摘　　要：为了探讨竹类植物对高频度酸雨胁迫的光合响应特性及其机制,以园林观赏竹种菲白竹(Pleioblastus fortunei)为材料,通过模拟不同强度酸雨(pH=2.0、3.0、4.0)高频度处理,研究其对叶绿素含量、光合作用日变化及叶绿素荧光特性的影响。结果表明:各胁迫处理组均导致菲白竹叶片叶绿素相对含量下降,酸度越强,降幅越大。酸雨胁迫导致光合速率日变化从对照的"单峰型"向"双峰型"转变,呈现明显的"午休"现象。随着胁迫强度的增加,净光合速率(P_n)、气孔导度(G_s)、蒸腾速率(T_r)、气孔限制值(L_s)均呈下降趋势,而胞间二氧化碳浓度(C_i)总体上则呈上升趋势,表明酸雨胁迫抑制光合速率主要由非气孔限制所致。不同强度的酸雨胁迫均使菲白竹PSⅡ最大光化学效率(F_v/F_m)、PSⅡ潜在活性(F_v/F_o)、PSⅡ有效光化学效率(F_v'/F_m')、PSⅡ实际光化学效率(ΦPSⅡ)、光化学淬灭系数(qP)显著降低,而非光化学淬灭系数(q_(NPQ))显著增加。经过1个多月的恢复期,pH4.0处理组各荧光参数恢复趋势明显;而pH 2.0处理组则无法恢复,表明菲白竹对p H 4.0的酸雨胁迫处理表现出较强的自我修复能力。其中,qNPQ的增强可能是菲白竹防御酸胁迫下光破坏的一种重要机制。In order to explore the photosynthetic response characteristic of bamboos to the high frequency of acid rain stress, the relative content of chlorophyll, the diurnal variation of photosynthesis and chlorophyll fluorescence in the leaves of Pleioblastus fortunei, an ornamental bamboo species were determined by foliar spraying with simulated acid rain （SAR） in different intensity of pH （2.0,3.0,4.0）. The results showed that treating with different intensity of SAR could result in the decrease of the relative content of chlorophy. The lower was the pH value, was the greater the decrease. The acid rain stress led to diurnal variation changing from the control “single peak” to “bimodal”, which present obviously photosynthetic depression at midday. With the increase of stress intensity, net photosynthetic rate （ Pn ） , stomatal con-ductance （ Gs ） , transpiration rate （ Tr ） and stomatal limitation （ Ls ） decreased. while, the increasement of the intercel-lular CO2 concentration （ Ci ） indicated that the decline of photosynthetic rate was mainly caused by non-stomatal limiting factor under acid rain stress. In addition, the determination of fluorescence parameters showed that SAR of different in-tensity made PSⅡ photochemical efficiency （ Fv/Fm ） , the largest PSⅡ activity of potential （ Fv/Fo ） , PSⅡ photo-chemical efficiency （ Fv′/Fm′） , PSⅡ photochemical efficiency （ΦPSⅡ） , photochemical quenching （ qP ） significantly lower, but the non-photochemical quenching （NPQ） was significantly increased. After the recovery of a month, the fluo-rescence parameters of P.fortunei under pH 4.0 treatment could mostly recover;However, all of P.fortunei under pH 2.0 can-t recover. It shows that P. fortunei treated with SAR of pH 4.0 has a strong ability to repair itself, but with pH 2.0, it can-t recover through self-regulation. The enhancement of NPQ in P. fortunei might be a vital mechanism for the resis-tence to light under the acid stress.

关 键 词：高频度模拟酸雨 菲白竹 光合日变化 叶绿素荧光 

分 类 号：Q945.78[生物学—植物学]