Spot blotch tolerance in barley is associated with early accumulation of hydrogen peroxide and jasmonic acid in leaves

A. Aldaoude*, M. Jawhar, Al-Shehadah, A. Shoaib

Volume 28, Issue 4;
Pages: 340-344; 2022
ISSN: 2069-0053 (print) (former ISSN: 1453-1399), Agroprint;
ISSN (online): 2068-9551

Spot blotch (SB), caused by the fungus Cochliobolus sativus, is an economically important disease of barley worldwide. Barley plants combat SB infection by eliciting a wide array of signaling pathways. To understand barley defense mechanisms towards this disease, the involvement of hydrogen peroxide (H₂O₂) and Jasmonic acid (JA) in tolerant ‘Banteng’ and susceptible ‘WI2291’ cultivars at early points of infection with the virulent C. sativus pathotype Pt4 was investigated. Data showed increasing accumulation of H₂O₂ and JA 24 hours post inoculation (hpi) as compared with the non-inoculated controls.  It is noteworthy that JA signaling was activated in parallel with H₂O₂ signaling up to 48h and then decreased at 72h in both cultivars. However, data revealed higher levels of H₂O₂  (0.92 µmol/g FW) in the tolerant cv. ‘Banteng’ as compared with the susceptible one ‘WI2291’ (0.33 µmol/g FW) 72hpi. The obtained results suggest that H₂O₂ and JA accumulation might have important role during barley - C. sativus interaction.