Improving quality and water tolerance in strawberry through combined application of Nano Zinc and Brassinosteroids

Strawberry ( Fragaria × ananassa Duch.), are vulnerable to water limitations due to their root structure and high-water content. The experiment was carried out as a factorial experiment in a randomized complete block design with three replications. water deficiency at 4 levels (100% of FC, 75% of FC, 50% of FC, and 25% of FC), brassinosteroid at 4 levels (control, 100, 200, and 400 ml/liter), and zinc nanoparticles (control, 1, 2, and 3 g/liter) in Sabrina cultivar were treated. The results showed, the highest fruit weight (20.53 g) was observed under 75% FC and 400 ml L ^− 1 Br in combination with 3 g L ^− 1 nano zinc. the interaction between Br and nano zinc (1.79 N) resulted in the lowest firmness in the treatment with 25% drought stress and 1 g L ^− 1 of nano zinc. Also, the application of Br (200 ml L ^− 1 ) and nano zinc (2 g L ^− 1 ) under FC (25%) enhanced the accumulation of TSS (11.6%) in the fruit. content of TS had the highest value (1.137 gr ^− 1 FW) in fruit subjected to mild FC (75%) with the application of 400 ml L ^− 1 Br combined with 2 g L ^− 1 nano Zn. The highest Fo was observed in fruits treated with 75% FC and 400 ml L ^− 1 Br in combination with 3 g L ^− 1 nano zinc. The lowest Fo was recorded under moderate drought stress and Br in combination with 3 g L ^− 1 nano zinc. The lowest Fv/Fm was found after 50% FC and 100 ml L ^− 1 Br treatment in combination with 2 g L ^− 1 nano zinc. Thus, foliar application of nano zinc and brassinosteroids under drought stress conditions can be considered an effective strategy to enhance growth, quality, and stress tolerance in the ’Sabrina’ strawberry cultivar.