Changes in primary metabolite content may affect thrips feeding preference in soybean crops.

Area of Science:

• Plant-insect interactions
• Plant biochemistry
• Crop science

Background:

• Plant defense responses are well-studied for chewing insects.
• Limited knowledge exists on plant reactions to piercing-sucking insects like thrips.
• Understanding soybean responses to Caliothrips phaseoli is crucial for crop management.

Purpose of the Study:

• To investigate metabolite changes in soybean leaves induced by thrips damage.
• To compare responses between two soybean cultivars with differing susceptibility.
• To identify potential feeding cues influencing thrips preference.

Main Methods:

• Used Nuclear Magnetic Resonance (NMR) spectroscopy to analyze leaf metabolites.
• Exposed field-grown soybean cultivars (cv. Charata and cv. Williams) to thrips damage for six days.
• Assessed thrips colonization and feeding preference on treated and untreated leaves.

Main Results:

• Thrips damage reduced sucrose concentration in both soybean cultivars.
• Pinitol, a major soluble carbohydrate, was induced in cv. Charata but not cv. Williams.
• Cv. Charata exhibited lower thrips colonization and higher levels of trigonelline and tyrosine.

Conclusions:

• Soybean cultivars exhibit differential metabolic responses to thrips infestation.
• Plant soluble carbohydrates (sucrose, pinitol) do not solely determine thrips feeding preference.
• Other compounds or leaf physical characteristics likely mediate thrips host selection.