Abstract

Manganese (Mn) is an important micronutrient in plant development. In order to test its capability to delay the senescence related oxidative stress in perennial ryegrass (Lolium perenne L.); a pot experiment was conducted in China Agriculture University during 2009 and 2010. Plants were sprayed with Manganese at 51 days after sowing then leaves were harvested at both 53 and 55 days after sowing for analyzing superoxide anion production and antioxidation enzymes activity. Results indicated that Mn clearly enhanced the dry weight of individual plants by 34%, inhibited the lipid peroxidation through decreasing the malondialdehyde (MDA) by 26 and 24% in 53 and 55 days after sowing, respectively, prevented chlorophyll from decomposing and maintained the integrity of cell membrane. Meanwhile, the activity of superoxide dismutase (SOD) was increased in Mn treatment group by 13.8 and 11.9% in 53 and 55 days after sowing compared with control group, Mn effectively increased the proline content of treatment plants by 16.3 and 18.2% over the control plants in 53 and 55 days after sowing, respectively. So the results significantly proved that Mn can delay the senescence induced by drought in perennial ryegrass. 

Key words: Manganese, senescence, oxidants, antioxidative enzymes.