Integrative Biology Journals

Plant Diversity ›› 2014, Vol. 36 ›› Issue (05): 611-621.DOI: 10.7677/ynzwyj201413243

• Articles • Previous Articles     Next Articles

Influence of Elevated CO2 Concentration and Nitrogen Source on Photosynthetic Traits in the Invasive Species Eupatorium adenophorum (Asteraceae)

OUYANG-Fen-1、2, ZHENG Guo-Wei-1, LI Wei-Qi-1、3   

  1. 1 Germplasm Bank of Wild Species in Southwest China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China; 2 University of Chinese Academy of Sciences, Beijing 100049, China; 3 Biology Department, Honghe University, Mengzi 661100, China
  • Received:2013-12-24 Online:2014-03-25 Published:2014-09-25
  • Supported by:

    NSFC (31070262), West Light Foundation of the Chinese Academy of Sciences (CAS), Germplasm Bank of Wild Species

CO2浓度升高和不同氮源对紫茎泽兰生长及光合特性的影响

欧阳芬1、2, 郑国伟1, 李唯奇1、3   

  1. 1 中国科学院昆明植物研究所中国西南野生生物种质资源库,云南 昆明650201; 2 中国科学院大学,北京100049;3 红河学院生物系,云南 蒙自661100
  • 基金资助:

    NSFC (31070262), West Light Foundation of the Chinese Academy of Sciences (CAS), Germplasm Bank of Wild Species

Abstract:

Increases in the concentration of atmospheric CO2 and plant invasion are two important problems that face humans worldwide. In some plants, exposure to a shortterm elevated concentration of CO2 (SE[CO2]) promotes photosynthesis, but the promotion of elevated [CO2] (E [CO2]) to photosynthesis might disappear after longterm treatment (socalled “CO2 acclimation”); this might result from the associated inhibition of nitrate assimilation. The present study investigated the physiological effects of shortterm (8 days) and longterm (40 days) exposure to E[CO2] when these were combined with different forms of inorganic N (full N; nitrate (NO3-)N) in the invasive species Eupatorium adenophorum. Exposure to E[CO2] increased the biomass of Eadenophorum, regardless of the duration of exposure to E[CO2] and the type of inorganic N that was supplied. E[CO2] could promote the photosynthesis of Eadenophorum seedlings fertilised with nondepleted Hoagland solutions (full N). For plants fertilised with NH4+depleted Hoagland solution (NO3-N), LE[CO2] treatment promoted the photosynthesis of Eadenop horum, but the promotion of photosynthesis by E[CO2] disappeared under SE[CO2] conditions. Photosynthetic pigments contents were determined to estimate potential changes in the photosynthetic capacity of Eadenophorum. For plants fertilised with nondepleted Hoagland solution, there were no significant differences in chlorophyll among the three [CO2] treatments, but the treatment of SE[CO2] increased the levels of chlorophyll in leaves. The apparent promotion of biomass accumulation and photosynthesis at LE[CO2] without a decrease in chlorophyll indicates that Eadenophorum might not acclimate to longterm exposure to E[CO2]. NH4+ depletion did not affect the capacity of LE[CO2] to promote the photosynthesis of Eadenophorum. Thus, considering some plants fertilised with NO3- acclimating to LE[CO2], Eadenophorum might be more competitive in areas where the soils are relatively poor in NH4+ as levels of atmospheric CO2 continue to rise.

Key words: Elevated CO2, Eadenophorum, Invasive plants, Photosynthesis acclimation, NO3- assimilation

摘要:

大气CO2浓度升高和植物入侵是全世界面临的两大重要问题。CO2浓度升高促进植物的光合作用,但在某些植物中,这种促进作用出现在短期高浓度CO2下,而在长期高浓度CO2处理下消失(称为CO2驯化),被认为源于高浓度CO2对光呼吸和NO3-同化的抑制。通过比较研究不同形式氮源(全氮、硝态氮)和短期(8days)、长期(40days)CO2浓度升高处理对入侵植物紫茎泽兰生理特征的影响,结果表明在全氮供应下,短期和长期CO2浓度升高均促进了紫茎泽兰的光合;氨态氮缺失情况下,长期CO2浓度升高促进紫茎泽兰的光合,而短期CO2浓度升高对紫茎泽兰的光合没有促进作用;缺NH4+下,短期高浓度CO2提高了叶片叶绿素含量,长期CO2升高又使其回复到正常CO2下的较低水平。这些结果表明紫茎泽兰并不会对长期的CO2升高产生驯化,即长期CO2升高会促进紫茎泽兰的光合作用,而且这一促进作用不受土壤中缺NH4+的影响。鉴于培养介质中缺NH4+会导致一些植物产生“CO2驯化”,未来CO2浓度升高情况下,在缺NH4+的土壤中,紫茎泽兰的竞争力可能会更强。

关键词: CO2浓度升高, 紫茎泽兰, 入侵植物, 光合驯化, NO3-吸收

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