郭卫珍 张亚利 奉树成

摘要： 以束花品種玫瑰春和茶梅品种小玫瑰为试验材料，采用Hoagland营养液水培法，研究了不同浓度（0 mmol/L、20 mmol/L、40 mmol/L、80 mmol/L、120 mmol/L）NaCl处理对2个山茶品种盐害及叶绿素荧光特性的影响，并就此探讨2个品种的耐盐性差异。结果表明，未经盐胁迫处理的小玫瑰的qP、ФPS II、ETR值均显著高于玫瑰春（P<0.05）;低盐浓度（20 mmol/L、40 mmol/L）胁迫下，2个山茶品种的盐害较轻，叶绿素荧光参数均与对照无显著差异（P>0.05），此时小玫瑰的盐害率、盐害指数以及Fv/Fm和Fv/Fo的下降幅度均小于玫瑰春;随着盐浓度的增加，2个山茶品种的盐害率和盐害指数增大，Fv/Fm和Fv/Fo均降低，且盐浓度越高，降低幅度越明显。其中较高盐浓度（120 mmol/L）胁迫下，玫瑰春的盐害率和盐害指数小于小玫瑰，此外玫瑰春的qN值上升幅度以及其他5个叶绿素荧光参数的下降幅度均显著低于小玫瑰（P<0.05）。综上得出，低盐浓度（≤40 mmol/L）对供试的2个山茶品种的生长影响较小，其中小玫瑰在非盐处理环境下的实际光化学效率和电子传递速率优于玫瑰春，在低盐浓度（20 mmol/L、40 mmol/L）下的耐盐性高于玫瑰春，在较高盐浓度（120 mmol/L）时玫瑰春的耐盐性高于小玫瑰，具有潜在的耐盐能力。

关键词： 山茶;NaCl胁迫;盐害;叶绿素荧光特性

中图分类号： S685.140.1 文献标识码： A 文章编号： 1000-4440（2021）03-0562-08

Effects of NaCl stress on salt injury and chlorophyll fluorescence characteristics of two Camellia cultivars

GUO Wei-zhen， ZHANG Ya-li， FENG Shu-cheng

（Shanghai Research Center of Urban Plant Resources Development and Application & Engineering and Technology， Shanghai Botanical Garden， Shanghai 200231， China）

Abstract： Camellia hybrid Meigui Chun and C.sasanqua Xiao Meigui were used as experiment materials and water culture methods using Hoagland nutrient solution was adopted to study the influence of different NaCl concentrations （0 mmol/L， 20 mmol/L， 40 mmol/L， 80 mmol/L， 120 mmol/L） on salt injury and chlorophyll fluorescence characteristics of two camellia varieties， and the difference of two camellia varieties in salt tolerance was discussed. The results showed that， the photochemical quenching coefficient （qP）， actual photochemical quantum efficiency （ФPSⅡ） and electron transport rate （ETR） value of Xiao Meigui were significantly higher than Meigui Chun without salt stress treatment （P<0.05）. Under salt stresses with low concentrations （20 mmol/L， 40 mmol/L）， the salt injury of two camellia cultivars was slight and the chlorophyll fluorescence parameters showed no significant difference compared with CK （P>0.05）， and the salt injury degree， salt injury index and decline range of PSⅡ maximum photochemical efficiency （Fv/Fm） and PSⅡ potential activity （Fv/Fo） of Xiao Meigui were less than those of Meigui Chun. As the salt concentration increased， the salt injury degree and salt injury index of two camellia varieties increased， while Fv/Fm and Fv/Fo decreased， the decrease range became more obvious as the salt concentration increased. Under higher salt concentration （120 mmol/L） stress， the salt injury degree and salt injury index of Meigui Chun were less than those of Xiao Meigui. In addition， the increase range of non-photochemical quenching coefficient （qN） and the decrease range of other five chlorophyll fluorescence parameters of Meigui Chun were significantly less than those of Xiao Meigui （P<0.05）. In summary， two camellia cultivars can grow normally under low salinity stresses （≤40 mmol/L）， and the practical photochemical efficiency and electron transfer rate of Xiao Meigui are better than those of Meigui Chun without salt stress. Under low salt concentrations （20 mmol/L， 40 mmol/L）， salt tolerance of Xiao Meigui is higher than Meigui Chun， but the salt tolerance of Meigui Chun is higher than that of Xiao Meigui under salt stress with high concentration （120 mmol/L）， which shows potential ability of salt tolerance.

Key words： Camellia;NaCl stress;salt injury;chlorophyll fluorescence characteristics

山茶（Camellia）作为世界名花和中国十大传统名花之一，观赏价值极高，在园林中的应用也十分广泛。传统山茶喜酸性土壤，而目前全世界正面临着土壤盐碱化的难题，中国盐碱地面积占现有耕地面积的10%[1-2]，可见盐碱土壤已成为限制山茶栽培和应用范围扩大的主要问题之一。目前，关于山茶耐盐碱方面的研究较少，张亚利等[3]对部分山茶在华东地区的生长情况及栽培土壤进行分析，认为影响其生长的土壤因子主要是pH和水溶性盐浓度（EC），郭卫珍等[4]通过观测发现山茶品种玫玉能够适应低盐浓度的土壤环境。

玫瑰春是由连蕊茶组（Camellia Sect. Theopsis Cohen-Stuart）原种杂交选育获得的束花品种，兼适应性好、抗逆性强等特性，具有广阔的应用前景，但对其耐盐性尚未进行系统研究。……