Efficacy of Biostimulants under Drought Stress

An agricultural scientist is investigating the efficacy of two novel biostimulants designed to enhance the drought tolerance of young olive trees (Olea europaea).

Sixty olive saplings of identical age and genetic clone were selected. The saplings were randomly divided into three groups of twenty:

• Group 1 was treated with a microalgal extract biostimulant.
• Group 2 was treated with a mycorrhizal fungi inoculation.
• Group 3 received only standard irrigation with no biostimulant.

All three groups were subjected to identical deficit-irrigation schedules (reduced watering) for 10 weeks to simulate drought conditions. At the end of the trial, physiological stress was quantified via leaf relative water content (RWC).