Effect of salinity on germination and growth of Pennisetum macrourum in southern Tasmania.
The salinity tolerance of P. macrourum was determined in order to define its potential habitats in the Derwent River estuary of S. Tasmania. NaCl and PEG 6000 reduced seed germination of P. macrourum to a greater extent than that of Lolium perenne and Agropyron elongatum. Reduction of vegetative reproduction by NaCl and PEG 6000 was greater in P. macrourum than in Phragmites australis. In nutrient culture, increasing NaCl conc. reduced growth of test plants in the order P. macrourum (seedling) (greatest reduction), A. elongatum, P. macrourum (vegetatively reproduced), L. perenne, P. australis (least reduction). These results, together with conductivity measurements on water and soil samples from the Derwent River estuary, indicate that P. macrourum is unlikely to spread downstream from present infestations.