Premium
Investigating indices to explain the impacts of ozone on the biomass of white clover ( Trifolium repens L. cv. Regal) at inland and coastal sites in Spain
Author(s) -
Bermejo V.,
Gimeno B. S.,
Granados I.,
Santamaría J.,
Irigoyen J. J.,
Bermejo R.,
Porcuna J. L.,
Mills G.
Publication year - 2002
Publication title -
new phytologist
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.742
H-Index - 244
eISSN - 1469-8137
pISSN - 0028-646X
DOI - 10.1046/j.1469-8137.2002.00497.x
Subject(s) - trifolium repens , phytotoxicity , ozone , stomatal conductance , biomass (ecology) , horticulture , relative humidity , botany , environmental science , agronomy , photosynthesis , biology , chemistry , meteorology , organic chemistry , physics
Summary• Ozone (O 3) phytotoxicity is driven by the concentrations the plants are exposed to, and also by meteorological and physiological variables. Thus, O3uptake might be a better indicator of the phytotoxicity of this pollutant than O3 exposure. • An ozone biomonitoring system based on the biomass ratio between an ozone‐resistant (NC‐R) and an ozone‐sensitive (NC‐S) biotype of white clover ( Trifolium repenscv. Regal) has been tested for 4 yr at four Spanish sites experiencing wide differences in their climatic and ozone exposure profiles. A complementary experiment was also carried out in open‐top chambers exposing plants of both biotypes to three O3treatments. Ozone exposure, air temperature, relative humidity and leaf stomatal conductance to water vapour were measured during the life span of both clover clones. These measurements enabled the total O3accumulated dose (CUMFO3 ) for each biotype to be calculated. • The biomass ratio of both clones was best correlated with indices based on O 3uptake, rather than with indices related to O3exposure. In fact, the best performance of the system was achieved when O3uptake > 40 nl l−l(CUMFO3 40) was considered. • The results support the need to relate O 3phytotoxicity to actual plant O3 uptake.