Arthropod predator nutrient content changes with wheat sowing period but is not driven by prey availability

Area of Science:

• Agricultural Entomology
• Ecology
• Biochemistry

Background:

• Conservation biocontrol is vital for sustainable crop pest management.
• Agricultural practices significantly influence natural enemy populations, but impacts are not fully understood.
• Crop sowing timing may alter resource availability, affecting predator nutrition and function.

Purpose of the Study:

• To investigate how crop sowing timing affects arthropod predator nutrition.
• To determine if differences in predator nutrition correlate with prey availability.
• To assess the implications for natural enemy effectiveness in pest control.

Main Methods:

• Collected arthropod predators and prey from winter- and spring-sown wheat plots.
• Quantified predator macronutrient content (carbohydrates, lipids, proteins) using colorimetric assays.
• Compared predator nutrition and prey abundance using multivariate and null network models.

Main Results:

• Significant differences in predator nutrient content, particularly carbohydrates, were observed between winter- and spring-sown wheat.
• Prey abundances also differed between sowing times.
• Neither recent nor current prey availability fully explained the observed differences in predator nutrition.

Conclusions:

• Crop sowing timing influences arthropod predator nutrition, likely due to changes in prey quality rather than quantity.
• Altered predator nutritional states may affect the movement and efficacy of natural pest enemies between crops.
• Understanding these dynamics is crucial for optimizing conservation biocontrol strategies.