Salicylic Acid Induces Resistance in Rubber Tree against Phytophthora palmivora

Abstract

Induced resistance by elicitors is considered to be an eco-friendly strategy to stimulate plant defense against pathogen attack. In this study, we elucidated the effect of salicylic acid (SA) on induced resistance in rubber tree against Phytophthora palmivora and evaluated the possible defense mechanisms that were involved. For SA pretreatment, rubber tree exhibited a significant reduction in disease severity by 41%. Consistent with the occurrence of induced resistance, the pronounced increase in H2O2 level, catalase (CAT) and peroxidase (POD) activities were observed. For defense reactions, exogenous SA promoted the increases of H2O2, CAT, POD and phenylalanine ammonia lyase (PAL) activities, including lignin, endogenous SA and scopoletin (Scp) contents. However, SA had different effects on the activity of each CAT isoform in the particular rubber tree organs. Besides, three partial cDNAs encoding CAT (HbCAT1, HbCAT2 and HbCAT3) and a partial cDNA encoding PAL (HbPAL) were isolated from rubber tree. Moreover, the expressions of HbCAT1, HbPAL and HbPR1 were induced by SA. Our findings suggested that, upon SA priming, the elevated H2O2, CAT, POD and PAL activities, lignin, endogenous SA and Scp contents, including the up-regulated HbCAT1, HbPAL and HbPR1 expressions could potentiate the resistance in rubber tree against P. palmivora.

Comparative Analyses of Four Chemicals Used to Control Black Mold Disease in Tomato and Its Effects on Defense Signaling Pathways, Productivity and Quality Traits

“…Additionally, Xu and Tian [ 70 ] reported that treatment with salicylic acid increased the CAT activity and stimulated the expression of CAT genes in sweet cherry fruits. On the other hand, pre-harvest spraying of rubber trees with salicylic acid induced the accumulation of catalase and peroxidase in the leaves [ 71 ]. Additionally, Hortensia et al [ 72 ] observed that the exogenous application of chemical elicitors such as chitosan and salicylic acid during different stages in the development of tomato fruits significantly increased the activity of catalase and peroxidase enzymes in the fruit tissue.…”

Integrated Proteomic and Metabolomic Profiling of Phytophthora cinnamomi Attack on Sweet Chestnut (Castanea sativa) Reveals Distinct Molecular Reprogramming Proximal to the Infection Site and Away from It

“…Contrasting evidence exists about the role of SA signaling during Phytophthora infection. Whereas SA-pretreatment on rubber tree reduced the disease symptoms against P. palmivora [ 52 ], P. cinnamomi attack on chestnut did not alter SA levels [ 53 ]. Interestingly, we detected increased SA levels in stem sections both proximal and distal to the infection ( Figure 6 B), indicating that P. cinnamomi mounts a defense response similar to that triggered by biotrophic pathogens.…”

Changes in Nematode Communities and Functional Diversity With the Conversion of Rainforest Into Rubber and Oil Palm Plantations

“…The decrease in bacterivore nematodes with the conversion of rainforest into plantations may have been due to the reduction of certain bacterial groups, especially in rubber plantations. Rubber plants produce salicylic acid to control microbial pathogens (Kästner et al, 2014;Deenamo et al, 2018) and this may reduce certain prey species of bacterivores. However, in general, the abundance and diversity of bacteria benefitted from the conversion of rainforest into plantations, presumably due to fertilizer application and liming (Ettema et al, 1999;Schneider et al, 2015).…”