Selection of Tomato and Cucumber Accessions for Waterlogging Sensitivity through Morpho-Physiological Assessment at an Early Vegetative Stage

Abstract

Waterlogging anomalies have recently increased, causing a reduction in yield and the loss of billions of dollars. Plant selection for increased tolerance to stress factors requires parameters with high sensitivity, as well as fast and inexpensive measurements. The aim of this study was to select tomato and cucumber accessions that reveal sensitivity and tolerance to waterlogging stress at an early vegetative stage. The selection of effective criteria for assessing plants was also an important issue. A total of 19 cucumber (including four highly homozygous) and 16 tomato accessions were evaluated, and plants with three true leaves were examined. The root zone of stressed plants was waterlogged for 7 days in a deep container. Morphological and physiological characteristics were obtained after 7 days of treatment and used for cluster analysis for discrimination of tolerant and sensitive accessions. Significant decreases in Fv/F0, Fv/Fm, Area, PI ABS, ET0/ABS, and ET0/TR0 parameters, as well as increases in DI0/RC, were observed in sensitive accessions, with no changes in tolerant plants. The OJIP test parameters (Fv/F0, PI ABS, DI0/RC, and Area) were more sensitive in selecting for waterlogging stress than Fv/Fm. The present research can be used in breeding programs. Selected accessions will support a detailed explanation of the physiological differences in response to waterlogging stress in tomato and cucumber plants.

Long-Term Waterlogging as Factor Contributing to Hypoxia Stress Tolerance Enhancement in Cucumber: Comparative Transcriptome Analysis of Waterlogging Sensitive and Tolerant Accessions

“…The DH2 and DH4 cucumber accessions were assessed as tolerant (WL-T) and sensitive (WL-S), respectively, after 7 days of hypoxia treatment [ 10 ]. Here, the aim of analysis of morphological traits was confirmation of differential stress response of both DH cucumber lines.…”

“…It was shown that under 8 days of waterlogging, biomass accumulation (DM:FM) was higher in treated cucumber plants, however the level of tolerance of tested cucumber was not provided. We carried out our analysis of a set of accessions with evidenced tolerance level [ 10 ], so based on our results, DM:FM has no impact on the tolerance level to hypoxia stress in tested lines. The second waterlogging (2xH) resulted in slower plant growth and biomass increase compared to the control plants, which may be due to the fact that, plants were focused on processes related to overcoming stress and not on the growth.…”

“…In the recovery period, oxidative stress has been shown to be induced in plants because of dehydration caused by dysfunction of the root system and consequent generation of ROS, ABA, and ethylene [ 19 , 88 ]. Here, we exploited two cucumber accessions differing in waterlogging tolerance [ 10 ] and we compared the expression profiles of genes in plants after 14 days of recovery compared to control plants. Differential recovery between the WL-T DH2 and WL-S DH4 accessions was related to the activity of genes related to carbohydrate metabolic processes, which were significantly up-regulated in the WL-S accession.…”

“…Cucumber ( Cucumis sativus L.), due to its shallow root system [ 7 ], is considered as being sensitive to the stress of limited oxygen access [ 6 , 8 , 9 , 10 ]. Differences in the response to oxygen deprivation between waterlogging (WL) tolerant (WL-T) and WL sensitive (WL-S) accessions using the RNA-Seq approach were evaluated in Arabidopsis thaliana [ 11 ], rice ( Oryza sativa ) [ 12 ], rapeseed ( Brassica napus L.) [ 13 ], soybean ( Glycine max ) [ 14 ], kiwifruit ( Actinidia deliciosa ) [ 15 ], sesame ( Sesamum indicum L.) [ 16 ], and cucumber [ 17 ].…”

“…However, these studies focused mainly on the response to hypoxic stress in the initial stages; there are no data from RNA-Seq studies carried out in cucumber roots regarding long-term waterlogging in WL-S and WL-T accessions. Understanding the mechanisms involved in the response to hypoxia in tolerant genotypes will enable the development of cultivars resistant to excess water in the soil in areas at risk of waterlogging [ 10 ].…”