Relative toxicity of heavy metals to red pine pollen germination and germ tube elongation

Journal Article · · J. Environ. Qual.; (United States)

OSTI ID:5997066

Chaney, W R; Strickland, R C

Heavy metals are known to affect vegetative growth of plants, but little is known concerning the effects of these environmental pollutants on reproductive processes. Hence, the effects of Cd/sup 2 +/, Hg/sup 2 +/, Pb/sup 2 +/, Cu/sup 2 +/, Zn/sup 2 +/, and Ba/sup 2 +/ on red pine (Pinus resinosa Ait.) pollen germination and germ tube elongation were determined in vitro in a series of nine aqueous solutions with concentrations that ranged from 0.56 ..mu..mol L/sup -1/ to 71.16 ..mu..mol L/sup -1/ for each cation. Large differences among metals in inhibition of the two growth parameters were found. Based on the lowest concentration significantly inhibiting germination, Cd/sup 2 +/ was the most toxic ion followed by Cu/sup 2 +/ > Hg/sup 2 +/ > Pb/sup 2 +/ >> Zn/sup 2 +/ > Ba/sup 2 +/. Similarly, the order for metal inhibition of tube elongation was Cd/sup 2 +/ > Pb/sup 2 +/ > Hg/sup 2 +/ Cu/sup 2 +/ >> Zn/sup 2 +/ > Ba/sup 2 +/. Compared with the other ions, Zn/sup 2 +/ and Ba/sup 2 +/ were relatively nontoxic. The concentration (effective dose) of each metal necessary to produce a 10% reduction of germination and tube elongation (ED/sub 10/) was calculated from linear regression equations. The ED/sub 10/ for germination for Cd/sup 2 +/ was 0.27 ..mu..mol L/sup -1/ and was 2.2, 2.5, and 19.0 times less than the ED/sub 10/ for Hg/sup 2 +/, Cu/sup 2 +/, and Pb/sup 2 +/, respectively. In comparison, the Cd/sup 2 +/ ED/sub 10/ for germ tube growth was 1.00 ..mu..mol L/sup -1/. Although the concentrations of Cd/sup 2 +/, Hg/sup 2 +/, and Pb/sup 2 +/ that produced inhibitory effects in vitro occur in the environment, extrapolation of these results to in vivo conditions is cautioned.

• Research Organization: Purdue Univ., W. Lafayette, IN
• OSTI ID: 5997066
• Journal Information: J. Environ. Qual.; (United States), Vol. 13:3
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
BARIUM COMPOUNDS
TOXICITY
CADMIUM COMPOUNDS
GERMINATION
INHIBITION
LEAD COMPOUNDS
MERCURY COMPOUNDS
PLANT GROWTH
ZINC COMPOUNDS
CATIONS
COMPARATIVE EVALUATIONS
DOSE-RESPONSE RELATIONSHIPS
EXPERIMENTAL DATA
PINES
POLLEN
ALKALINE EARTH METAL COMPOUNDS
CHARGED PARTICLES
CONIFERS
DATA
GAMETES
GERM CELLS
GROWTH
INFORMATION
IONS
NUMERICAL DATA
PLANTS
TREES
560303* - Chemicals Metabolism & Toxicology- Plants- (-1987)