摘要
【目的】以入侵种空心莲子草(Alternanthera philoxeroides)与本土伴生种马唐(Digitaria sanguinalis)为研究对象,探讨UV⁃B辐射、施氮及其交互效应对二者竞争的影响,以期为全球变化下的入侵植物防治提供科学依据。【方法】依据de Wit取代试验法,在单种、混种盆栽模式下分别设置处理方式(施氮、UV⁃B辐射、施氮×UV⁃B辐射)、物种属性(空心莲子草、马唐)2个因子,测定各处理组合下的植物总生物量、形态、色素及光合荧光等指标,并采用二因素方差分析和LSD多重比较法分析以上各指标差异。【结果】①单种模式中,施氮导致植物最大茎长和马唐叶面积显著增加207.154%和297.643%、空心莲子草总生物量及稳态光适应光化学猝灭系数(qp_Lss)显著降低40.612%和52.381%;UV⁃B辐射导致植物最大茎长、空心莲子草最大光量子产率(QY_max)及稳态光量子效率(QY_Lss)显著增加117.607%、404.459%和835.714%,导致马唐QY_Lss显著降低45.605%;施氮×UV⁃B辐射导致空心莲子草总生物量及马唐QY_max显著降低79.310%和18.984%,空心莲子草QY_max显著增加685.350%,施氮×UV⁃B辐射还使得空心莲子草暗适应后最小荧光(F_(0))下降而QY_Lss增加、马唐F_(0)增加而QY_Lss下降。②混种模式中,施氮导致马唐叶面积及其叶绿素a指数(Chla)显著增加254.259%和53.018%,导致空心莲子草根长及其Chla显著降低76.051%和12.084%;UV⁃B辐射导致空心莲子草Chla显著增加45.434%;施氮×UV⁃B辐射导致空心莲子草根长显著降低58.824%。【结论】施氮相对增加了马唐在生物量及形态上的优势,但UV⁃B辐射削弱马唐光合活性而增加空心莲子叶绿素含量;且UV⁃B辐射、施氮×UV⁃B辐射交互作用显著提升空心莲子草的实际光化学效率。全球变化下应加强空心莲子草入侵监控,以防多类因子交互效应加剧其对于本土植物的竞争替代。
【Objective】The present paper aimed to examine the effects of enhanced UV⁃B radiation,nitrogen addition and their interaction on the interspecific competition between invasive weed Alternanthera philoxeroides and its native accompanying species Digitaria sanguinalis,providing reference for the control of invasive plants under the global change.【Method】According to the de Wit substitution test method,we totally set two experimental factors that contained the treatment method(nitrogen addition,UV⁃B radiation,nitrogen×UV⁃B)and the species(A.philoxeroides,D.sanguinalis)on the mono and mixed potting cultures,measured the total biomass,morphology,pigment,and photosynthetic fluorescence of these two studied plant species,and then used the two⁃way ANOVA and the least significant difference(LSD)multiple comparisons to examine the differences of above indicators with different treatment combinations.【Result】(i)In the monoculture,nitrogen addition led to a significant increase in the maximum stem length of plants and leaf area of D.sanguinalis by 207.154%and 297.643%,and a significant decrease in the total biomass and qp_Lss of A.philoxeroides by 40.612%and 52.381%,respectively.UV⁃B radiation led to a significant increase in the maximum stem length of plants,QY_max and QY_Lss of A.philoxeroides by 117.607%,404.459%and 835.714%,respectively,and a significant decrease in the QY_Lss of D.sanguinalis by 45.605%.The interaction effect led to a significant decrease in the total biomass of A.philoxeroides and QY_max of D.sanguinalis by 79.310%and 18.984%,and a significant increase in the QY_max of A.philoxeroides by 685.350%,respectively.The interaction effect also led to an opposite trade⁃off of F_(0)and QY_Lss between these two studied plant species.(ii)In the mixed culture,nitrogen addition led to a significant increase in the leaf area and Chla of D.sanguinalis by 254.259%and 53.018%,respectively,and a significant decrease in the root length and Chla of A.philoxeroides by 76.051%and 12.084%,respectively.UV⁃B radiation led to a significant increase in the Chla of A.philoxeroides by 45.434%.The interaction effect led to a significant decrease in the root length of A.philoxeroides by 58.824%.【Conclusion】Nitrogen addition relatively increased the competitive advantage of D.sanguinalis in terms of biomass and morphology,but UV⁃B radiation weakened its photosynthetic activity and increased the chlorophyll content of A.philoxeroides.Furthermore,UV⁃B radiation and its interaction with nitrogen addition significantly increased the actual photochemical efficiency of A.philoxeroides.Thus,we should strengthen the monitoring of A.philoxeroides invasion under global change,to prevent the interaction of multiple factors aggravating the competitive substitution of native plants by this invader.
作者
吴昊
姜俊慧
罗莉
崔益萌
张婉莹
WU Hao;JIANG Jun-hui;LUO Li;CUI Yi-meng;ZHANG Wan-ying(College of Life Sciences,Xinyang Normal University,Xinyang,Henan 464000,China;Henan Dabieshan National Field Observation and Research Station of Forest Ecosystem,Zhengzhou 450046,China;Xinyang Academy of Ecological Research,Xinyang,Henan 464000,China)
出处
《西南农业学报》
CSCD
北大核心
2024年第2期344-352,共9页
Southwest China Journal of Agricultural Sciences
基金
国家自然科学基金项目(31800460)
河南省科技攻关计划项目(232102110062)
河南省高等学校重点科研项目(24A180028)
信阳生态研究院开放基金项目(2023XYMS16)
信阳师范大学“南湖学者奖励计划”青年项目(2023A017)。
关键词
空心莲子草
竞争
氮素
植物入侵
光合荧光
UV⁃B辐射
Alternanthera philoxeroides
Competition
Nitrogen
Plant invasion
Photosynthetic fluorescence
UV⁃B radiation
