Boron toxicity tolerance in barley may be related to intrinsically higher levels of reactive oxygen species in the shoots

There is considerable intra-and interspecific variation in boron (B) toxicity tolerance crop plants. In this study, we aimed to investigate the mechanisms involved excess B barley (Hordeum vulgare) early stages of plant development. To do this, B-sensitive (B?lb?l-89) and B-tolerant (Tarm-92) cultivars were grown hydroponically under control stress conditions (10 mM H3BO3) for 4 or 7 days. The hydrogen peroxide (H2O2), malondialdehyde (MDA), total phenolic, flavonoid, anthocyanin, proline, sugar contents, as well DPPH radical scavenging capacity, then determined both cultivars. Our results showed that treatment led significant increases concentration exposure times. However, there no drastic differences roots shoots between sensitive tolerant While dry root weight B?lb?l-89 was reduced after days (p < 0.05), such a decrease not observed Tarm-92. H2O2, MDA, sugar, anthocyanin contents increased considerably response during at least one period 0.05). H2O2 content Tarm-92 significantly greater than B?lb?l-89, but difference MDA capacity two Finally, 35% increase found flavonoid seedlings exposed conclusion, findings study suggest may be related their tolerate higher levels reactive oxygen species.