Intercropping Alters Phytochemicals Associated With Insect Herbivory.

Area of Science:

• Agroecology
• Plant Chemical Ecology
• Sustainable Agriculture

Background:

• Interspecific chemical interactions can modify plant phytochemical profiles.
• Intercropping with diverse neighbors may enhance crop defense compounds.
• Volatile organic compounds (VOCs) play a role in plant defense signaling.

Purpose of the Study:

• To assess how intercropping affects plant biomass and VOC emissions.
• To investigate the impact of intercropping on induced VOC profiles under herbivory.
• To understand plant responses to intercropping and insect herbivory.

Main Methods:

• Intercropping sweetclover (Melilotus alba) and wheat (Triticum aestivum) with silflower (Silphium integrifolium).
• Assessing plant biomass and aerial VOC emissions.
• Conducting an in-situ bioassay with fall armyworm (Spodoptera frugiperda) to study induced VOCs.

Main Results:

• Prenol lipids (terpenoids) upregulated in silflower under intercropping and herbivory.
• Carboxylic acids and organooxygen compounds altered in sweetclover by intercropping and herbivory.
• Wheat and sweetclover biomass increased, while silflower biomass remained unaffected.

Conclusions:

• Intercropping and herbivory significantly alter VOC emissions in diverse plant species.
• These alterations in VOCs may influence insect herbivory resistance.
• Optimizing intercropping systems can enhance natural plant defenses for sustainable agriculture.