Abstract:

This study investigated the effects of glutathione （GSH） priming on the antioxidant capacity of aged oat （Avena sativa） seed embryo mitochondria， aiming to provide scientific evidence for the improving outcomes of storage and utilization of seeds. Using 5-day-old aged seeds， this experiment examined the variations in antioxidant enzyme activity， and antioxidant and hydrogen peroxide （H₂O₂） contents in embryo mitochondria treated by priming with 0.2 mmol·L^-1 GSH for 24 hours. The results indicated that seed aging significantly （P<0.05） increased the H₂O₂ content in the embryo mitochondria and significantly （P<0.05） decreased the activities of antioxidant enzymes catalase （CAT）， peroxidase （POD）， superoxide dismutase （SOD）， ascorbate peroxidase （APX）， monodehydroascorbate reductase （MDHAR）， glutathione reductase （GR）， and dehydroascorbate reductase （DHAR）. The content of ascorbic acid （AsA） showed no significant change， while GSH content， AsA/dehydroascorbic acid （DHA） ratio， and GSH/oxidized glutathione （GSSG） ratio significantly （P<0.05） increased， and DHA and GSSG contents significantly （P<0.05） decreased. Moreover， GSH priming treatment in aged seeds significantly （P<0.05） decreased H₂O₂ content and significantly （P<0.05） increased the activities of CAT and GR in the embryo mitochondria. POD， SOD， MDHAR， APX， DHAR activities， AsA and DHA contents and GSH/GSSG ratio showed an increase， GSH and GSSG contents and AsA/DHA ratio showed a decrease， but none of these differences were significant. In conclusion， GSH priming treatment effectively mitigated oxidative damage and maintained seed vigor mainly by enhancing mitochondrial antioxidant enzyme activities and reducing H₂O₂ content in aged oat seed embryos.

Key words: GSH priming, seed aging, oat, antioxidant capacity, seed vigor