Assessing Tomato Genotypes for Organic Hydroponic Production in Stressful Environmental Conditions

Abstract

Identifying tomato genotypes that can thrive and produce abundantly under arid climatic conditions and addressing the growing food demand caused by population growth are pressing concerns for food security. This research aimed to assess the growth, physiological, phenological, fruit yield, and postharvest quality of tomato genotypes cultivated in an organic hydroponic system in Qatar, where abiotic stress conditions prevail. Ten different tomato genotypes were carefully evaluated, and comprehensive data regarding their growth and development were collected and analyzed. The performance of these tomato genotypes across all traits related to yield and quality showed significant variations. Notably, the ‘Velocity’ and ‘Sigma’ genotypes consistently exhibited robust vegetative growth and improved phenological characteristics compared with the other tomato cultivars. Specifically, ‘Velocity’ and ‘Sigma’ displayed increased leaf assimilation rates (35% and 32%), stomatal conductance (14% and 11%), and reduced transpiration loss (50% and 44%) compared with ‘SV4129TH’. These genotypes also showed lower electrolyte leakage (32% and 28%) and maintained higher intercellular CO2 concentrations. Furthermore, ‘Velocity’ exhibited an accelerated flowering pattern, with the first flowering occurring 4 days sooner and 50% flowering occurring 5 days sooner than that of ‘SV4129TH’. ‘Velocity’ also demonstrated superior fruit set (14%), pollen viability (24%), and fewer incidences of flower drops (36%) compared with ‘SV4129TH’. Notably, ‘Velocity’ outperformed ‘SV4129TH’ in terms of marketable fruit yields, with a 32% higher yield. In addition to its impressive yield, ‘Velocity’ exhibited superior postharvest quality, including firmness, Brix level, acidity, and color. Therefore, overall, ‘Velocity’ and ‘Sigma’ emerged as promising genotypes with strong abiotic stress tolerance capabilities. The correlation analysis of these traits provided valuable insights into the selection and breeding of genotypes that can withstand abiotic stress conditions, laying the foundation for effective comparisons and selections of genotypes suitable for organic hydroponic cultivation in stressful environments.

Keywords

• abiotic stress
• arid climate
• fruit yield
• hydroponic system
• ‘velocity’
• ‘sigma’