Salicylic acid and ethylene signaling pathways are involved in production of rice trypsin proteinase inhibitors induced by the leaf folder Cnaphalocrocis medinalis (Guenée)

Abstract

The roles of signaling pathways in the production of trypsin proteinase inhibitors (TrypPIs) in rice infested by the leaf folder (LF) Cnaphalocrocis medinalis were studied. Infestation by LF increased TrypPI levels in the leaves of rice plants at the tillering, booting and flowering stages but decreased TrypPI levels at the ripening stage; TrypPI levels in rice stems did not increase at any developmental stage. Infestation by LF at the tillering stage systemically increased TrypPI levels in leaves but not in stems; it also enhanced salicylic acid (SA) levels in leaves and stems, and the ethylene level released from plants. However, LF infestation did not increase JA concentrations. Exogenous application of SA or ethylene enhanced TrypPI levels in the leaves and stems of plants at the tillering stage, whereas treatment with both SA and ethylene induced lower levels of TrypPIs than treatment with SA or ethylene alone, suggesting an antagonistic effect of SA and ethylene on TrypPIs induction. The results suggest that both SA and ethylene signaling pathways are involved in the production of TrypPIs in rice induced by LF; moreover, the antagonistic effect of SA and ethylene may explain the changes in TrypPI levels seen at different plant developmental stages and in different organs.rice, Cnaphalocrocis medinalis, jasmonic acid, salicylic acid, ethylene, trypsin proteinase inhibitor, herbivore-induced defense response Citation:Wang X, Hu L C, Zhou G X, et al. Salicylic acid and ethylene signaling pathways are involved in production of rice trypsin proteinase inhibitors induced by the leaf folder Cnaphalocrocis medinalis (Guenée).

Activity of defense related enzymes and gene expression in pigeon pea (Cajanus cajan) due to feeding of Helicoverpa armigera larvae

“…In our experiment, TI activity was found to increase in all the treated samples with respect to the control. A similar induced response was reported in rice (Casaretto et al 2004;Wang et al 2011). In addition amylase inhibitors, which act as an inhibitor of larval midgut amylase (Kluh et al 2005) accumulates due to foliar treatment with exogenous jasmonic acid was observed, previously (Délano-Frier et al 2004).…”

Effects of exogenous methyl jasmonate and salicylic acid on rice resistance toOebalus pugnax

“…Studies of the regulation of these volatile compounds in plants show that their expression is often triggered by specific elicitors of herbivores that activate signaling pathways and genes related to plant defense . Rice plants that suffered herbivory from the rice leaffolder had increased levels of endogenous SA, and increased SA led to induced production of trypsin proteinase inhibitors . Zhao et al ., in contrast, did not find increases in SA levels in plants subjected to herbivory by S. frugiperda , but emission of methyl salicylate was higher in plants with S. frugiperda injury.…”

OsNPR1 negatively regulates herbivore‐induced JA and ethylene signaling and plant resistance to a chewing herbivore in rice

“…TrypPIs and HIPVs are important direct and indirect defense chemicals in rice against herbivores, and their production is regulated by JA, SA and ET signaling pathways (Zhou et al , Lu et al , Qi et al , Wang et al ). Therefore, we investigated if OsNPR1 modulates the production of TrypPIs and HIPVs.…”

“…Both JA and ET pathways have been reported to play an important role in mediating herbivore‐induced rice defense responses, including a positive regulation for the production of TrypPIs and HIPVs (Zhou et al , Lu et al , Lu et al , Qi et al , Wang et al ). Furthermore, in rice, TrypPIs have been reported to influence the performance of SSB (Zhou et al ), and HIPVs protect plants from attack by herbivores by attracting the natural enemies of the herbivores (Lou et al, , , Qi et al ).…”