Impact of CO2 Enrichment on Growth, Yield and Fruit Quality of F1 Hybrid Strawberry Grown under Controlled Greenhouse Condition

Carbon dioxide enrichment inside a greenhouse is a sustainable approach to increasing crop production worldwide. Recently, the F1 hybrid strawberry became an alternative to runner-propagated cultivation as an innovative method to shorten the production period and increase strawberry production. This work aims to present CO2 enrichment as a sustainable tool that improves the yield in a controlled greenhouse and addresses the efficiency of three F1 hybrid strawberry varieties grown under Saudi Arabian conditions. A greenhouse experiment was conducted at the National Research and Development Center for Sustainable Agriculture (Estidamah), KSA, to study the impact of two CO2 levels (400 ppm ("ambient") and 600 ppm ("enrichment")) on the growth, photosynthesis traits, fruit yield and fruit quality of three F1 hybrid strawberry varieties grown under soilless culture conditions. The results show that CO2 enrichment significantly improved the phenotyping of strawberry growth traits at 60 days post-transplanting. The physiological response of the varieties to CO2 enrichment reveals a significant increase in the photosynthetic rate (129.7%) and intercellular CO2 (43.7%) in the leaves of strawberry exposed to CO2 enrichment rather than in ambient conditions, combined with a significant increase in the number of fruits per plant (27.5%) and total fruit yield (42.2%). A similar pattern was observed with varieties D and S in terms of fruit number, length and diameter. However, CO2 at 600 ppm promoted total soluble solid accumulation and vitamin C for the tested varieties. In contrast, CO2 enrichment significantly decreased nitrogen, phosphorus, potassium and magnesium accumulation in the leaves of the exposed plants in comparison to 400 ppm of CO2. These results suggest that increasing CO2 enrichment could contribute to an increase in strawberry yield and nutritional value and demonstrate that understanding the response of each variety to CO2 enrichment is important to support selecting suitable greenhouse strawberry varieties to improve crop yield.