Home among the gum trees - not necessarily so for silverleaf nightshade

摘要

Silverleaf nightshade is a widespread weed in south-eastern Australia. Despite many years of use of synthetic herbicides, populations of this deep rooted summer active weed continue to pose a problem, with more infestations occurring. As part of an innovative management strategy, the phytotoxic potential of eucalyptus species was evaluated.Aqueous extracts were prepared from ground Eucalyptus spathulata, E. salubris, E. brockwayii and E. dundasii leaves. Germination of silverleaf nightshade seed was significantly decreased by aqueous extracts from all species. Results suggest that compounds in the aqueous extract exhibit a phytotoxic effect on silverleaf nightshade seed germination. Further research is being conducted to determine the effect of these compounds on mature silverleaf nightshade plants. Phytochemical or possible allelopathiccontrol of silverleaf nightshade may allow development of innovative new management options such as bioherbicides or use of agrofor-esry for weed management.