Eliciting maize defense pathways aboveground attracts belowground biocontrol agents

Area of Science:

• Ecology
• Entomology
• Plant Pathology

Background:

• Plant defense mechanisms are crucial for mediating complex interactions within ecosystems, affecting both aboveground and belowground organisms.
• Understanding these plant-mediated interactions is key to developing sustainable pest management strategies.

Purpose of the Study:

• To investigate how aboveground stimulation of plant defense pathways in corn affects interactions involving aboveground and belowground herbivores (Diabrotica speciosa) and a subterranean natural enemy (Heterorhabditis amazonensis).

Main Methods:

• Experimental manipulation of corn plants to simulate herbivory and methyl salicylate treatment.
• Observation of the recruitment behavior of adult and larval Diabrotica speciosa to treated and untreated plants.
• Assessment of the attraction of the entomopathogenic nematode Heterorhabditis amazonensis to corn plants experiencing different herbivory levels.

Main Results:

• Adult Diabrotica speciosa were observed to recruit to plants with simulated aboveground herbivory and methyl salicylate treatment.
• Larval Diabrotica speciosa showed less specific recruitment patterns.
• The entomopathogenic nematode Heterorhabditis amazonensis demonstrated recruitment towards corn plants previously fed upon by adult Diabrotica speciosa.

Conclusions:

• Belowground natural enemies like entomopathogenic nematodes can detect and respond to aboveground plant defense signaling.
• Induced plant defenses can be leveraged to enhance biological control efficacy in agricultural systems.
• This study highlights the interconnectedness of aboveground and belowground ecological interactions and their potential for integrated pest management.