Accumulation of salicylic acid, jasmonic acid and phytoalexins in rice, Oryza sativa, infested by the white-backed planthopper, Sogatella furcifera (Hemiptera: Delphacidae)

Abstract

In order to clarify the mechanism of induced resistance to blast disease in rice, Oryza sativa, that had been previously infested by the white-backed planthopper, Sogatella furcifera Horváth, we first investigated the accumulation of salicylic acid (SA) and jasmonic acid (JA) in rice plants infested by the planthopper. The results confirmed that infestation of S. furcifera strongly stimulates the production of SA and JA in rice. These results indicate that both salicylate-and jasmonate-mediated pathways (SA and JA pathways), which are involved in the general defense system in plants, were activated in rice infested by S. furcifera. Further results confirmed that S. furcifera infestation induces accumulation of a major rice diterpenoid phytoalexin, momilactone A, and a flavonoid phytoalexin, sakuranetin, which are well known as antimicrobial chemicals, particularly in blast disease caused by the blast fungus, Magnaporthe oryzae B. Couch. All these results strongly suggest the following hypothetical mechanism of induced-resistance to M. oryzae in rice infested by S. furcifera. First, S. furcifera releases some elicitor-active compounds, which might be produced in the salivary glands, into the rice plant during feeding. Next, the defense signal systems, SA-and JA-mediated pathways, are activated by the elicitor. Finally, phytoalexins are induced in rice as antimicrobial compounds mainly through activation of the JA-mediated pathway.

Multiple roles of plant volatiles in jasmonate-induced defense response in rice

“…[1][2][3] It is also well known that JA plays an important role in rice defense responses. [4][5][6][7][8] In addition, it has been revealed that JA treatment causes the accumulation of plant volatile compounds in rice. [9][10][11] Plant volatile compounds, such as terpenoids and C 6 volatiles, are emitted from microbe-infected or wounded plant sites, and are potential signal compounds that induce defenses against tissue damage from herbivores and plant pathogens.…”

Combining effects of ozone and Xanthomonas oryzae pv. oryzae on antioxidants and phytoalexins in rice (Oryza sativa L.)

“…Normally, the high amount of phytoalexin was found close to damaged area from the disease attack (Großkinsky et al, 2012). Phytoalexins would directly damage cell wall of intruding microorganisms by inhibiting growth, interfering metabolism and retarding colonizing process of pathogenic disease (Kanno et al, 2012). This experiment showed that after rice leaves were clipped and inoculated by Xanthomonas oryzae pv.…”

“…oryzae (c). under abiotic and biotic (Dillon et al, 1997;Liu et al, 2012;Kanno et al, 2012), depend on type of stress. In this experiment the results showed that ozone had more capacity to induce sakuranetin rather than momilactone A.…”

Relation between O3-Inhibition of Photosynthesis and Ethylene in Paddy Rice Grown under Different CO2Concentrations

“…According to Yang et al (2004), rice had two orders of magnitude higher levels of SA than tobacco and Arabidopsis, and was insensitive to exogenous SA. In addition, Kanno et al (2012) reported that JA and SA contents in rice leaves were increased by the feeding damage of white-back planthopper (Sogatella furcifera), but the increment of SA was less than that of JA because rice plants contain much higher levels of endogenous SA in healthy tissues. Therefore, we conclude that the role of SA in rice is less pronounced than in other plants, and that JA and ethylene are major components of signal transduction causing O 3 injury.…”