摘要
【目的】探讨盐胁迫对中华常春藤(Hedera nepalensis var.sinensis)生理特性的影响,以及外源NO对植株盐胁迫的缓解效应。为提高植株耐盐性及其在盐渍地区的推广应用提供参考依据。【方法】以中华常春藤水培苗为试验材料,进行不同浓度盐胁迫及叶面和根际施用NO供体SNP处理,测定其相关生理指标。【结果】(1)300 mmol/L盐处理下,中华常春藤叶片叶绿素a(Chla)和b(Chlb)及总量、电子传递速率(ETR)、最大光化学量子产量(F_(v)/F_(m))、实际光化学量子产量(Y_((Ⅱ)))降至最低,分别是对照(CK)的23%、20%、23%、41%、51%和41%,而丙二醛(MDA)含量却升至最高,相比CK增加了88%。过氧化氢酶(CAT)、抗坏血酸过氧化物酶(APX)、过氧化物酶(POD)活性和可溶性物质含量在不同程度盐胁迫下均显著增加。(2)100 mmol/L盐浓度下,叶面喷施和根际施用SNP组比未施用组叶绿素总量、ETR、F_(v)/F_(m)以及Y_((Ⅱ))分别上升了80%/2%、61%/21%、13%/11%和106%/56%。(3)300 mmol/L盐浓度下,叶面喷施和根际施用SNP组比未施用组叶绿素总量、ETR、F_(v)/F_(m)以及Y_((Ⅱ))分别上升了73%/35%、92%/18%、36%/15%和86%/50%;此外,抗氧化酶活性和可溶性物质含量均在300 mmol/L盐胁迫和叶面喷施SNP共同处理下达到最大值。【结论】高浓度盐胁迫导致中华常春藤叶片膜脂过氧化严重,光合机构受损,光合速率显著下降。而外施SNP可通过提高光合色素含量、抗氧化酶活性及可溶性物质含量等缓解盐胁迫对植株的伤害,且以叶面喷施SNP的缓解效果最佳。
[Objective]This study investigated the effects of salt stress on physiological characteristics of Hedera nepalensis var.sinensis,and the alleviating effect of exogenous NO on salt stress,which willprovide a reference for improving plant salt tolerance and its application in saline areas.[Methods]The hydroponic seedlings of H.nepalensis var.sinensis were treated with different concentrations of salt stress,and treatments of NO with sodium nitroprusside(SNP),including foliar spraying and rhizosphere application,the relevant physiological indexes of H.nepalensis var.sinensis were measured.[Results]The results showed that:(1)Under 300 mmol/L salt treatment,the photosynthetic pigments,including chlorophyll a(Chla),chlorophyll b(Chlb),total chlorophyll content(Chl(a+b))were decreased significantly,the chlorophyll fluorescence parameters,including electron transport rate(ETR),maximum photochemical quantum yield(F_(v)/F_(m))and actual photochemical quantum yield(Y_((Ⅱ)))of H.nepalensis var.sinensis decreased significantly,which were 23%,20%,23%,41%,51%and41%of the control group(CK),respectively,while the content of membrane lipid peroxidation product malondialdehyde(MDA)reached the highest level,with an increase of 88%compared with CK.In addition,with different degrees of salt stress,the activities of catalase(CAT),ascorbate peroxidase(APX),peroxidase(POD)and the content of soluble substances increased significantly.(2)Under the salt concentration of 100 mmol/L condition,compared with the none-application group,the total content of chlorophyll and the chlorophyll fluorescence parameters,including ETR,F_(v)/F_(m)and Y_((Ⅱ))of the foliar spraying SNP group increased by 80%,61%,13%and 106%respectively,while the total content of chlorophyll,ETR,F_(v)/F_(m)and Y_((Ⅱ))of the rhizosphere application SNP increased by 2%,21%,11%and 56%respectively.(3)Under the salt concentration of 300 mmol/L condition,compared with the none application group,the chlorophyll content and the chlorophyll fluorescence parameters,including ETR,F_(v)/F_(m)and Y_((Ⅱ))of foliar spraying SNP increased by 73%,92%,36%and 86%respectively,while the total content of chlorophyll,ETR,F_(v)/F_(m)and Y_((Ⅱ))of rhizosphere application SNP increased by 35%,18%,15%and 50%respectively.Furthermore,the activities of antioxidant enzymes and the accumulation of soluble substances content reached the maximum value under 300 mmol/L salt stress and foliar spraying SNP.[Conclusion]High concentration of salt stress resulted in severe peroxidation of membrane lipid,damage of photosynthetic mechanism and significant decrease of photosynthetic rate.While applying SNP with foliar and rhizosphere methods can alleviate the damage of salt stress by increasing the content of photosynthetic pigment,the activities of antioxidant enzymes and the content of soluble substances.In addition,the foliar spraying is more effective than the rhizosphere application.
作者
张敏
李燕
宁朋
程小毛
黄晓霞
ZHANG Min;LI Yan;NING Peng;CHENG Xiaomao;HUANG Xiaoxia(College of Landscape Architecture and Horticulture Sciences,Southwest Forestry University,Southwest Landscape Architecture Engineering Research Center of State Forestry and Grassland Administration,Kunming 650224,China)
出处
《江西农业大学学报》
CAS
CSCD
北大核心
2022年第3期583-592,共10页
Acta Agriculturae Universitatis Jiangxiensis
基金
国家自然科学基金项目(31760197)。
关键词
中华常春藤
盐胁迫
外源一氧化氮
不同施用方式
Hedera nepalensis var.sinensis
salt stress
exogenous NO
different application methods