Transgressive Biochemical Response to Water Stress in Interspecific Eggplant Hybrids

Abstract

In a climate change scenario, crop tolerance to drought must be urgently improved, as it represents an increasingly critical stress reducing agricultural yields worldwide. Although most crops are relatively sensitive to water stress, many of their wild relatives are more tolerant and may be used to improve drought tolerance in our crops. In this study, the response to drought of eggplant (Solanum melongena), its close wild relatives S. insanum and S. incanum and their interspecific hybrids with S. melongena was assessed. The plants were subjected to two treatments for 18 days: control, with irrigation every four days, and drought, with complete interruption of irrigation. Morphological and biomass traits were measured, and physiological and biochemical responses were analysed using stress biomarkers such as proline, flavonoids, and total phenolic compounds. Oxidative stress was quantified by measuring malondialdehyde (MDA) content. As a result of the drought treatment, plant development and tissue water content were seriously affected. Generally, water deficit also caused significant increases in MDA, proline, flavonoids, and total phenolics compounds. Our results comparing parental accessions reveal a better response to drought in one of the S. insanum accessions. The hybrid between S. melongena and S. incanum displayed a better response than the other hybrids and even its parents. The results obtained here might be helpful for future eggplant breeding programmes aimed at improving drought tolerance.

Responses of interspecific hybrid eggplant f4 inbred lines to drought and heat stress

“…In a study, eggplant, its close wild relatives S. insanum and S. incanum and their interspecific hybrids with S. melongena were subjected to drought for 18 days. Their results which were support our results, showed that the hybrid between S. melongena and S. incanum displayed a better response than the other hybrids and even its parents (González-Orenga et al, 2023). On the 25 th day of the treatment 4 of 12 each 50 F4 plants showing "slow growth" (Scale = 1) were selected as "tolerant to drought" by using 0-5 scale.…”

Growth and antioxidant responses to water stress in eggplant MAGIC population parents, F1 hybrids and a subset of recombinant inbred lines

“…Prediction of polygenic traits, such as those tested in this trial, is usually a major challenge in hybrid generation [ 56 ]. These results are similar to those found in other studies that have evaluated F 1 eggplant hybrids under water stress, where the responses were diverse and complex due to the genetic distance of the parents [ 16 , 57 ], the generation of hybrids with parents presenting moderate genetic distances could be a better strategy, as it has been seen that they achieve better results in eggplant [ 58 ]. At the growth level, the hybrids did not stand out in any trait under water stress, but it was observed that two hybrids had lower H 2 O 2 content, which could indicate a lower level of oxidative stress [ 59 ], and one hybrid had lower proline content, which could indicate a lower level of stress [ 60 ].…”

“…The use of hybrid varieties has led to significant advances in agriculture, with the potential to increase production and resilience to biotic and abiotic stresses [ 15 ]. In eggplant, promising responses under water stress conditions have been identified through hybridization, with interspecific hybrids of S. melongena × S. incanum and S. melongena × S. insanum showing superior growth under limited water supply compared to their parents [ 16 ]. In addition, Multiparent Advanced Generation Intercrossing (MAGIC) populations are increasingly recognised as a powerful tool for plant breeding, facilitating the identification of genomic regions and the selection of recombinant lines with desired traits [ 17 ].…”

Use of Multivariate Analysis in Screening for Drought Tolerance in Ornamental Asteraceae Species

“…A comparison of straightforward growth metrics is often adequate for closely related genotypes, such as varieties or cultivars of one species or even species belonging to the same genus. Some examples include permanent wilting in cowpea [45], roots system size in barley [46], reduction of fresh shoots biomass accumulation in Juncus [47], foliar dehydration in Limonium [48], reduction of leaf area and leaf fresh weight in eggplants and its hybrids [49], and shoot and leaf dry weight in wild relatives of eggplant [50], amongst others. However, in addition to growth characteristics, physiological, biochemical, and more recently, omics approaches are also considered when screening a larger number of more distant genotypes for drought resistance [51][52][53][54][55][56][57] (amongst many others).…”