The effects of cadmium on biomass production and growth parameters of drunken horse grass (Achnatherum inebrians) over an 8-week period were determined in a controlled-environment experiment. Changes were determined for relative water content, anti-oxidative enzymes (i.e., catalase (CAT), Superoxide dismutase (SOD), peroxidase (POD), and ascorbate peroxidase (APX)) and for H2O2 content, as well as levels of proline, malondialdehyde (MDA), and chlorophylls "a" and "b" present within leaves infected with Neotyphodium gansuense vs. non-infected controls. Observations began 4 weeks after addition of CdCl2 (0, 50, 100 and 200 mu M) to the nutrient solution. Under high concentrations (100 and 200 mu M) of CdCl2, endophyte-infected plants produced more biomass and had higher values for plant height and tiller number compared to non-infected controls, but there was no significant difference (P > 0.05) under 0 and 50 mu M CdCl2. Anti-oxidative enzyme activities, H2O2 concentration, and chlorophylls "a" and "b" levels increased, but proline and malondialdehyde content declined in the infected plants vs. non-infected plants under high (100 and 200 mu M) concentrations of CdCl2. There was no significant difference (P > 0.05) under 0 and 50 mu M CdCl2. Endophyte infection was concluded to be of benefit to the growth and anti-oxidative mechanisms within A. inebrians under high concentrations exposures to CdCl2. (C) 2009 Elsevier B.V. All rights reserved.