Assessing the impact of different water stresses on physio-chemical properties and yield-related traits in tomato genotypes: Insights into stability and response

Tomato is a highly sensitive crop to moisture stress, and grown widely under varying conditions of moisture deficit. To identify the stable genotypes and characterize their responses to moisture stress, thirty-two diverse genotypes were evaluated at three imposed moisture regimes i.e., sub-optimal irrigation at 75±5% of the field capacity (FC; L1), irrigation at 50±5% of the FC (L2), and irrigation at 25±5% of the FC (L3) inside a passively ventilated plastic greenhouse. A wide range of variability was observed for 23 analyzed physio-chemical traits under study. All the analysed traits (except root-shoot ratio, chlorophyll index, total biomass, sugar content, and acidity) have shown higher heritability and moderate to high genetic advance, indicating that these traits are governed by additive gene action and responsive to selection under water stress conditions. All the growth and yield parameters were shown to decrease significantly with the increase of intensity of moistures stress. Likewise, physiological parameters, namely chlorophyll and the relative water content tended to decrease, while the rate of water loss and proline content tended to increase following an increase in stress level. Fruit quality traits like total sugar, vitamin-C, and lycopene contents were tended to improve with the increase of designated moisture stress. The additive main effects and multiplicative interaction (AMMI) analysis of variance revealed the significant effects of moisture stress, genotype, and genotype × environment interaction for yield and yield-related traits. Based on multi-trait stability index (MTSI) analysis, MT-11, VL Tomato-4 and Megha Tomato-3 were considered most stable and promising genotypes for promotion for commercial production under the moisture stress conditions.