Reduced fertilization regimes could boost biocontrol service without reducing crop yield

Area of Science:

• Agricultural Science
• Ecology
• Entomology

Background:

• Agricultural intensification alters ecological interactions, impacting pest control.
• Trophic networks are sensitive to changes in plant nutrition.

Purpose of the Study:

• To investigate how different fertilization levels affect biological control of aphids on tomato plants.
• To assess the performance of the parasitoid Aphidius ervi and the predator Adalia bipunctata under varying nutrient conditions.

Main Methods:

• Controlled greenhouse experiment with tomato plants, aphids (Macrosiphum euphorbiae), and two natural enemies (Aphidius ervi, Adalia bipunctata).
• Two fertilization levels (high vs. medium) were applied.
• Aphid densities, plant growth, and biocontrol agent efficiency were measured.

Main Results:

• High fertilization increased tomato plant growth and aphid populations.
• Parasitoid efficiency was reduced under high fertilization.
• Predator performance remained stable across fertilization levels.
• Biological control effectiveness is species-specific regarding plant nutrition.

Conclusions:

• Fertilization management is crucial for effective biological pest control.
• Excessive nutrients can benefit pests over natural enemies, compromising biocontrol.
• Tailoring fertilization to specific natural enemies can improve pest suppression and sustainable agriculture.