Enhancing Plant Growth and Yield Under Reduced Water and Nutrient Conditions: The Role of Biostimulants in Improving Irrigation Efficiency and Drought Resilience in Soilless Strawberry Cultivation Under Glasshouse Conditions

<p dir="ltr">Introduction: Strawberries are globally valued for their flavour, nutritional benefits and antioxidant content. However, their cultivation is highly sensitive to abiotic stresses, particularly water and nutrient limitations, which can impact yield and quality. Soilless systems like hydroponics offer a solution by improving irrigation efficiency in commercial strawberry cultivations. This study investigates the use of microbial biostimulants and protein hydrolysates to enhance water and nutrient use efficiency and drought tolerance in hydroponic strawberry production under glasshouse conditions.Method: The study was conducted at ARU Writtle's unheated glasshouse from May to November 2024, using two strawberry cultivars, ‘Loren’ and ‘Malwina’. Plants were grown in commercial compost media under two irrigation regimes (100% and 50%) and treated with biostimulants (Vitalnova TriBoost and Hicure). Measurements included plant growth, fruit yield, and physiological parameters. Statistical analysis was carried out using SPSS to assess treatment effects and correlations.ResultsBiostimulant treatments, significantly improved various growth and physiological traits, especially under deficit irrigation. In ‘Loren’, TriBoost moderately increased leaf production, while in ‘Malwina’, it significantly enhanced leaf count (14.4%), shoot fresh weight (52%), shoot water content (25.1%) and stomatal conductance (17%). Hicure improved stomatal conductance in both cultivars, suggesting improved physiological responses to reduced irrigation. Although biostimulants did not significantly influence fruit count, TriBoost and Hicure significantly improved fruit weight by 35.7% and 37.0% respectively in ‘Malwina’ under 50% irrigation.ConclusionThis study shows that biostimulants, particularly Hicure and TriBoost, can improve growth and physiological performance of hydroponically grown strawberries under reduced irrigation. However, yield increases were observed in only one cultivar, with no yield benefit in the other cultivar despite improved growth. These cultivar‐specific responses highlight the importance of tailored biostimulant use and provide valuable insights for growers, as biostimulants can support improved irrigation efficiency and drought resilience in soilless strawberry production.</p>