Crop Resilience to Drought With and Without Response Diversity

Area of Science:

• Ecology
• Agronomy
• Plant Science

Background:

• Droughts threaten crop productivity globally.
• Ecological theory posits higher species diversity enhances ecosystem resistance and resilience.
• Empirical evidence for diversity effects under drought is limited.

Purpose of the Study:

• To investigate if mixing two legume species with contrasting drought responses (alsike clover and black medic) enhances resistance and resilience to drought.
• To assess the role of response diversity and species identity in drought resilience.

Main Methods:

• Two pot experiments were conducted using sole crops and a mixture of alsike clover and black medic.
• Plants were subjected to cumulative drought stress and transient drought events.
• Aboveground biomass, resistance, and resilience were measured at different growth stages.

Main Results:

• The mixture was more productive than sole crops, but this effect decreased under drought stress.
• Response diversity was observed through asynchronous growth patterns post-drought.
• Sole alsike clover showed significant drought resilience; the mixture was more resilient than the average sole crop but not more than alsike clover alone.

Conclusions:

• Crop diversity can promote drought resilience via growth asynchrony.
• Species identity, particularly the traits of alsike clover, significantly influences drought resilience.
• While diversity can contribute, species-specific traits are crucial for drought-resilient agricultural systems.