BVOC emissions, photosynthetic characteristics and changes in chloroplast ultrastructure of Platanus orientalis L. exposed to elevated CO2 and high temperature.
To investigate the interactive effects of increasing [CO(2)] and heat wave occurrence on isoprene (IE) and methanol (ME) emissions, Platanus orientalis was grown for one month in ambient (380 micromol mol(-1)) or elevated (800 micromol mol(-1)) [CO(2)] and exposed to high temperature (HT) (38 degrees C/4 h). In pre-existing leaves, IE emissions were always higher but ME emissions lower as compared to newly-emerged leaves. They were both stimulated by HT. Elevated [CO(2)] significantly reduced IE in both leaf types, whereas it increased ME in newly-emerged leaves only. In newly-emerged leaves, elevated [CO(2)] decreased photosynthesis and altered the chloroplast ultrastructure and membrane integrity. These harmful effects were amplified by HT. HT did not cause any unfavorable effects in pre-existing leaves, which were characterized by inherently higher IE rates. We conclude that: (1) these results further prove the isoprene's putative thermo-protective role of membranes; (2) HT may likely outweigh the inhibitory effects of elevated [CO(2)] on IE in the future.
Velikova
Violeta
V
Bulgarian Academy of Sciences, Institute of Plant Physiology, Acad. G. Bonchev, Bl. 21, 1113 Sofia, Bulgaria. violet@bio21.bas.bg
Tsonev
Tsonko
T
Barta
Csengele
C
Centritto
Mauro
M
Koleva
Dimitrina
D
Stefanova
Miroslava
M
Busheva
Mira
M
Loreto
Francesco
F
D002070:Butadienes / Q000737:chemistry* / Q000378:metabolism; D002245:Carbon Dioxide / Q000378:metabolism*; D002736:Chloroplasts / Q000737:chemistry / Q000378:metabolism / Q000648:ultrastructure*; D045782:Hemiterpenes / Q000737:chemistry* / Q000378:metabolism; D006358:Hot Temperature; D019684:Magnoliopsida / Q000737:chemistry / Q000378:metabolism* / Q000648:ultrastructure; D000432:Methanol / Q000737:chemistry; D010420:Pentanes / Q000737:chemistry* / Q000378:metabolism; D010788:Photosynthesis; D018515:Plant Leaves / Q000737:chemistry / Q000378:metabolism / Q000648:ultrastructure; D055549:Volatile Organic Compounds / Q000737:chemistry* / Q000378:metabolism
D002070:Butadienes; D045782:Hemiterpenes; D010420:Pentanes; D055549:Volatile Organic Compounds; C005059:isoprene; D002245:Carbon Dioxide; D000432:Methanol