Tibouchina pulchra (Cham.) Cogn., a native Atlantic Forest species, as a bio-indicator of ozone: visible injury.
Tibouchina pulchra saplings were exposed to carbon filtered air (CF), ambient non-filtered air (NF) and ambient non-filtered air+40 ppb ozone (NF+O3) 8 h per day during two months. The AOT40 values at the end of the experiment were 48, 910 and 12,895 ppb h(-1), respectively, for the three treatments. After 25 days of exposure (AOT40=3871 ppb h(-1)), interveinal red stippling appeared in plants in the NF+O3 chamber. In the NF chamber, symptoms were observed only after 60 days of exposure (AOT40=910 ppb h(-1)). After 60 days, injured leaves per plant corresponded to 19% in NF+O3 and 1% in the NF treatment; and the average leaf area injured was 7% within the NF+O3 and 0.2% within the NF treatment. The extent of leaf area injured (leaf injury index) was mostly explained by the accumulated exposure of ozone (r2=0.89; p<0.05).
Departamento de Botânica, Instituto de Biociências, Universidade de São Paulo, CP 11461, 05422-970 São Paulo, SP, Brazil. furlancm@yahoo.com.br
Cláudia M
CM
Furlan
Regina M
RM
Moraes
Patricia
P
Bulbovas
Maria J
MJ
Sanz
Marisa
M
Domingos
Antonio
A
Salatino
D000393:Air Pollutants / Q000633:toxicity*; D018533:Biomass; D001938:Brazil; D004781:Environmental Exposure; D004784:Environmental Monitoring / Q000379:methods; D035322:Melastomataceae / Q000187:drug effects*; D010126:Ozone / Q000633:toxicity*; D018515:Plant Leaves / Q000187:drug effects*; D036226:Seedlings; D014329:Tropical Climate
D000393:Air Pollutants; D010126:Ozone