Lower Nitrogen Availability Enhances Resistance to Whiteflies in Tomato

Area of Science:

• Agricultural Science
• Plant Science
• Ecology

Background:

• Nitrogen (N) fertilizer application can increase crop yields but may enhance plant attractiveness to herbivores.
• Increased herbivory due to higher tissue N content can reduce plant resistance and crop production.

Purpose of the Study:

• To investigate the impact of reduced nitrogen (N) supplementation on tomato resistance to whiteflies.
• To assess the relationship between N availability, plant resistance, and tolerance to herbivores in different tomato varieties.
• To evaluate the trade-off between plant resistance and tolerance to herbivory.

Main Methods:

• Four tomato varieties were grown under varying levels of nitrogen (N) fertilization.
• Plant resistance to whiteflies and fruit production were measured.
• Plant tolerance to herbivore damage and root:shoot ratios were assessed.

Main Results:

• Plants receiving half the recommended N rate exhibited enhanced resistance to whiteflies without significant fruit yield reduction.
• Significant differences in resistance and tolerance to whiteflies were observed among tomato varieties.
• A clear trade-off between resistance and tolerance was identified in tomato plants.

Conclusions:

• Lowering nitrogen fertilization rates can improve tomato plant resistance to whiteflies, offering economic advantages.
• Reduced N input minimizes potential yield losses and decreases environmental costs associated with agrochemicals.
• Optimizing nitrogen fertilization balances crop yield, pest resistance, and environmental sustainability.