Bark extracts of Litsea glutinosa induces systemic resistance for controlling wilt of tomato caused by Ralstonia solanacearum

Ralstonia solanacearum (Smith) Yabuuchi et al. causes wilt disease of Tomato crops might be controlled by bark extracts of Litsea glutinosa (Lour.) C.B. Robinson. Bark extracts from L. glutinosa was screened against the test pathogen R. solanacearum which strongly reduced infection of tomato plants causing bacterial wilt disease. Crude methanolic bark extract displayed inhibition of R. solanacearum and exposed toxicity. After isolation, bark extracts were applied on the infected tomato plants in the field and greenhouse to determine the potency in regulating wilt disease in two successive years (2024 and 2025). Upregulation of the plant immune system in tomatoes, characterized by a substantial increase in pathogenesis-related proteins such as β-1,3-glucanase, peroxidase and defense-related compounds such as phenylalanine ammonia-lyase, polyphenoloxidase and phenolic substances were observed following application of bark extract in consecutive years. β-Sitosterol and Kaempferol were selected as active principle in bark extracts from L. glutinosa.