Effects of copper sulfate on black bindweed (Polygonum convolvulus L.).

Seedlings of black bindweed (Polygonum convolvulus L.) were transplanted to soil contaminated with copper sulfate at different dosages. These plants were followed until maturity under greenhouse conditions, and measures of mortality, growth, and reproduction were obtained from harvests 21, 34, and 105 days after the transplant. It was found that application of 125 mg Cu2+ kg-1 resulted in 1.7% lifetime mortality increasing to 100% at 500 mg kg-1. The mortality was dependent on exposure time. No further mortality was observed after 50 days. The population consisted of a relatively tolerant and a sensitive group. This was indicated by differences in lifetime of plants treated with 500 mg kg-1 and by a diversification in biomass of individuals dying from treatment with 315 mg kg-1. The plants surviving treatment had reduced biomass and seed production at dosages above 200 mg kg-1.