不同氮水平下内生固氮菌对入侵植物南美蟛蜞菊生长策略的影响  

Effects of endophytic nitrogen-fixing bacteria on the growth strategy of an invasive plant Sphagneticola trilobata under different nitrogen levels

作　　者：汪晶晶 王嘉浩 黄致云 Vanessa Chiamaka OKECHUKW 胡蝶 祁珊珊[2] 戴志聪 杜道林 WANG Jing-Jing;WANG Jia-Hao;HUANG Zhi-Yun;Vanessa Chiamaka OKECHUKW;HU Die;QI Shan-Shan;DAI Zhi-Cong;DU Dao-Lin(School of the Environment and Safety Engineering,Jiangsu University,Zhenjiang,Jiangsu 212013,China;Key Laboratory of Modern Agricultural Equipment and Technology,Ministry of Education,School of Agricultural Engineering,Jiangsu University,Zhenjiang,Jiangsu 212013,China;Jiangsu Collaborative Innovation Center of Technology and Material of Water Treatment,Suzhou University of Science and Technology,Suzhou,Jiangsu 215009,China)

机构地区：[1]江苏大学环境与安全工程学院,江苏镇江212013 [2]江苏大学农业工程学院现代农业装备与技术教育部重点实验室,江苏镇江212013 [3]江苏省水处理技术与材料协同创新中心,苏州科技学院,江苏苏州215009

出　　处：《植物生态学报》2023年第2期195-205,共11页Chinese Journal of Plant Ecology

基　　金：江苏省自然科学基金(BK20211321);国家自然科学基金(32171509和32071521);江苏省博士后科学基金(2021K160B);江苏省高校优势学科项目

摘　　要：很多因素可以影响外来植物的入侵性,其中内生菌可能扮演了极其重要的角色。为了探究内生固氮菌对入侵植物生长策略的影响,本研究分别在高和低两种氮水平下,种植接种和不接种内生固氮菌的入侵植物南美蟛蜞菊(Sphagneticola trilobata)和同属本地植物蟛蜞菊(S.calendulacea),对比研究它们的生长和氮含量。从南美蟛蜞菊茎段分离出内生固氮菌Kosakonia sp.WTB-JS007,发现其对南美蟛蜞菊和蟛蜞菊这两种植物生长策略的影响存在显著差异,且这种差异不受氮水平的影响。在低氮处理下,接种WTB-JS007对蟛蜞菊的生长及植株氮含量没有显著影响,但显著提高了南美蟛蜞菊的地上生物量(30.48%),促进了匍匐茎的伸长,减少了地下生物量(56.58%),并提高了植株总氮含量(47.51%)。类似地,在高氮水平下,内生固氮菌亦显著影响南美蟛蜞菊地上部分的生长,但对蟛蜞菊生长的影响不显著。这些结果表明,内生固氮菌对入侵和非入侵植物生长、生物量分配及氮获取的影响存在显著差异,而这种生长策略的差异有利于入侵植物地上部分的快速生长与扩张,从而提高其入侵性。Aims Many factors can influence the invasiveness of alien plants,and among them endophytes may play a key role.Thus,the aim of this study is to investigate the effects of endophytic nitrogen-fixing bacteria on the growth strategy of invasive plants.Methods We grew the invasive plant Sphagneticola trilobata and its native congener S.calendulacea infected by endophytic nitrogen-fixing bacteria or not under two nitrogen levels(low and high)and compared their growth and total nitrogen content.Important findings The endophytic bacteria Kosakonia sp.WTB-JS007,isolated from S.trilobata,had different effects on the growth strategy of the two species(S.trilobata and S.calendulacea)and such an effect did not depend on the nitrogen levels.Under the low nitrogen level,inoculation with WTB-JS007 showed no significant effect on the growth or total nitrogen content of S.calendulacea,but significantly increased aboveground biomass(by 30.48%),promoted stolon length,decreased belowground biomass(by 56.58%),and enhanced total nitrogen content(by 47.51%)of S.trilobata.Similarly,under the high nitrogen level,endophytic bacteria stimulated the aboveground growth of S.trilobata,but had no effect on that of S.calendulacea.These results suggest that endophytic nitrogen-fixing bacteria can differently affect the growth,biomass allocation and nitrogen uptake of invasive and its co-occurring native plant species.Such a difference in the growth strategy can facilitate the rapid growth and expansion of the aboveground part of invasive plants and thus promote their invasiveness.

关 键 词：入侵植物 无菌培养体系 氮 生长策略 新生境扩张 

分 类 号：Q948[生物学—植物学]