Bioprotection and grafting strategies to suppress pest pressure and improve yield of hydroponically grown organic tomato
The infestation of major greenhouse pests such as whitefly, leafminer, and thrips, coupled with hot and humid conditions, poses significant challenges in controlled environment horticulture, particularly in organic tomato production.
Low tomato productivity is attributed to pest pressure and the inadequate stress tolerance of existing cultivars, hindering their ability to optimize fruit set and yield.
While the individual impacts of bioprotection and grafting strategies have been extensively studied in conventional production systems, their combined effects in controlled environments remain less explored.
This study aimed to assess the efficacy of grafting (‘Maxifort’ × ‘Valdeon RZ’) and bioprotection strategies (yellow sticky traps, Spinosad, and Bacillus thuringiensis) in mitigating greenhouse pest infestation and enhancing the yield of organically grown hydroponic tomatoes in adverse environmental conditions in Qatar.
The experimental design employed a strip plot, with grafted ‘Valdeon RZ’ and non-grafted ‘Valdeon RZ’ as the main plot treatments, and yellow sticky traps, Spinosad, and Bacillus thuringiensis randomly assigned to the subplots.
Tomato cultivar ‘Valdeon RZ’ grafted on ‘Maxifort’ exhibited superior seedling quality, as evidenced by increased stem diameter and improved root attributes.
Grafted ‘Valdeon RZ’ plants treated with Spinosad demonstrated enhanced net assimilation rate (23%), stomatal conductance (17%), and membrane stability index (14%), along with reduced transpiration loss (20%) and electrolyte leakage (18%), while maintaining intercellular CO2 concentration.
Flowering occurred four days earlier in grafted ‘Valdeon RZ’ plants treated with Spinosad compared to untreated and non-grafted counterparts.
Among the bioprotection strategies, Spinosad exhibited superior pest control efficiency, followed by Bacillus thuringiensis and yellow sticky traps.
Spinosad-treated plants showed a 37.5% reduction in leafminer and a 25% decrease in whitefly incidence compared to untreated control plants by 11 weeks after transplanting.
Our findings can lead to practical strategies aimed at minimizing greenhouse pest infestations while improving tomato yield in an organic hydroponic system within a protected environment.
Dash, P.K., Guo, B. and Leskovar, D.I. (2025). Bioprotection and grafting strategies to suppress pest pressure and improve yield of hydroponically grown organic tomato. Acta Hortic. 1416, 385-392
DOI: 10.17660/ActaHortic.2025.1416.51
https://doi.org/10.17660/ActaHortic.2025.1416.51
DOI: 10.17660/ActaHortic.2025.1416.51
https://doi.org/10.17660/ActaHortic.2025.1416.51
yellow sticky traps, spinosad, Bacillus thuringiensis, ‘Valdeon RZ’, protected environments
English
1416_51
385-392