Rice defense responses are induced upon leaf rolling by an insect herbivore

Area of Science:

• Plant Science
• Chemical Ecology
• Entomology

Background:

• Plant defense mechanisms are crucial for survival against herbivores.
• Rice plants can detect and defend against Cnaphalocrocis medinalis feeding.
• The perception of C. medinalis leaf-rolling behavior by rice remains uninvestigated.

Purpose of the Study:

• To evaluate the role of C. medinalis leaf rolling in rice plant defense.
• To assess the indirect effects of leaf rolling on C. medinalis parasitoids.
• To understand rice's perception of leaf-rolling behavior.

Main Methods:

• Volatile profiling of undamaged, naturally rolled, and artificially rolled rice leaves.
• Gene-transcriptional profiling to identify defense-related gene expression.
• Phytohormonal profiling to measure jasmonic acid (JA) and salicylic acid (SA) levels.

Main Results:

• Natural leaf rolling by C. medinalis significantly increased attraction of parasitoids.
• Leaf rolling altered headspace volatile profiles, with natural rolling showing distinct patterns.
• Both leaf rolling and feeding upregulated defense genes; rolling increased SA, while feeding increased JA.

Conclusions:

• Rice plants can perceive the leaf-rolling behavior of C. medinalis.
• Leaf rolling acts as an early warning signal, initiating rice plant defenses.
• This perception enhances rice's ability to combat C. medinalis infestations.