Enhancing yield and fruit quality of strawberry cultivars through in vitro propagation

Abstract

Introduction: Strawberries (Fragaria × ananassa) are valued for their nutritional and functional properties, including vitamins, antioxidants, and bioactive compounds. In vitro propagation provides a means to produce uniform, virus-free planting material, potentially enhancing plant health and fruit quality.

Objective: This study evaluated the effects of propagation method—conventional runner propagation versus in vitro micropropagation—on fungal disease incidence, pest control efficacy, morphological development, yield, and fruit biochemical composition across six commercial strawberry cultivars.

Materials and Methods: Six strawberry cultivars (‘Lambada’, ‘Cabrillo’, ‘Alba’, ‘Murano’, ‘Jenny’, and ‘Aurora’) were propagated using virus-tested in vitro culture and conventional methods. Field trials employed a randomized block design with three replicates of 25 plants per treatment. Five fungal pathogens and three key pests (melon aphid, onion thrips, and two-spotted spider mite) were monitored after a single pesticide application. Morphological traits, yield, and fruit quality parameters (total sugars, vitamin C, and titratable acidity) were measured. Data were analyzed statistically using Student’s t-test (p < 0.05).

Results:  Micropropagated plants showed markedly reduced fungal disease incidence, especially Botrytis cinerea (gray mold) and Podosphaera aphanis (powdery mildew). For the ‘Lambada’ cultivar, B. cinerea incidence decreased from 40.8 ± 8.9% to 7.4 ± 3.1%, and P. aphanis from 28.3 ± 6.4% to 10.1 ± 2.1%. Pest control efficacy remained higher in in vitro plants, sustaining >90% suppression of aphids and thrips by day 10, compared with 68–96% in conventional plants. Although control of Tetranychus urticae declined over time, in vitro plants maintained 68–88% control, compared with 48% in traditional plants. Morphological assessments showed enhanced flowering, vegetative growth, yield, and fruit size in micropropagated plants; for example, ‘Cabrillo’ yield rose from 2100 ± 204 g to 2800 ± 217 g per plant. Fruits from in vitro plants contained significantly more total sugars (+0.5–1.3 g/100 g) and vitamin C (+3.0–5.1 mg/100 g). At the same time, titratable acidity was slightly lower (except in ‘Cabrillo’), resulting in a more favorable sugar-to-acid ratio.

Conclusion: In vitro propagation significantly improves strawberry production by reducing pathogen and pest incidence, enhancing vegetative growth and yield, and increasing key fruit quality traits. These findings support micropropagation as a sustainable strategy for producing high-quality, virus-free strawberry plants. Future work should integrate micropropagation with optimized pest management programs to address challenges, such as the persistence of two-spotted spider mites.

Keywords: strawberry (Fragaria × ananassa); in vitro propagation; micropropagation; functional food; fruit quality; yield improvement; sustainable agriculture