Differential Response of Two Tomato Genotypes, Wild Type cv. Ailsa Craig and Its ABA-Deficient Mutant flacca to Short-Termed Drought Cycles

Abstract

Two tomato genotypes with constitutively different ABA level, flacca mutant and wild type of Ailsa Craig cv. (WT), were subjected to three repeated drought cycles, with the aim to reveal the role of the abscisic acid (ABA) threshold in developing drought tolerance. Differential responses to drought of two genotypes were obtained: more pronounced stomatal closure, ABA biosynthesis and proline accumulation in WT compared to the mutant were compensated by dry weight accumulation accompanied by transient redox disbalance in flacca. Fourier-transform infrared (FTIR) spectra analysis of isolated cell wall material and morphological parameter measurements on tomato leaves indicated changes in dry weight accumulation and carbon re-allocation to cell wall constituents in flacca, but not in WT. A higher proportion of cellulose, pectin and lignin in isolated cell walls from flacca leaves further increased with repeated drought cycles. Different ABA-dependent stomatal closure between drought cycles implies that acquisition of stomatal sensitivity may be a part of stress memory mechanism developed under given conditions. The regulatory role of ABA in the cell wall restructuring and growth regulation under low leaf potential was discussed with emphasis on the beneficial effects of drought priming in developing differential defense strategies against drought.

Knockdown of NtCPS2 promotes plant growth and reduces drought tolerance in Nicotiana tabacum

“…Compared with WT, ABA content in leaves of the mutant tomato decreased by about 25%, resulting in more obvious stomatal opening and reduced drought resistance. The results of our study were similar to Živanović et al. (2021) , suggesting that the decrease of ABA content indirectly led to the sensitivity of plants to drought stress, and it was speculated that the increase of stomatal conductance caused by the decrease of ABA content could lead to the increase of water loss and the decrease of drought resistance of leaves ( Virlouvet and Fromm, 2014 ; Fleta-Soriano et al., 2015 ) In conclusion, after editing the NtCPS2 gene, the relative expression level of the NtCPS2 gene in NtCPS2 -knockdown tobacco decreased, and the content of GGPP increased.…”

“…(1972) also showed that the stomatal aperture of plant mutants with too low endogenous ABA level significantly increased. Živanović et al. (2021) found that the two ABA levels formed different tomato genotypes WT and flacca mutant tomato had different responses to drought.…”

Exogenous monoterpenes mitigate H2O2-induced lipid damage but do not attenuate photosynthetic decline during water deficit in tomato

“…Leaf water status declined with soil water content ( Fig. 1 ) as in other studies that fully withheld irrigation from tomato ( Živanović et al , 2021 ), with reduced water transport from roots to leaves ( Osakabe et al , 2014 ) causing Ψ leaf to decline ( Lambers et al , 2008 ). Exogenous MT applications did not affect this relationship.…”

Desiccation Tolerance in Ramonda serbica Panc.: An Integrative Transcriptomic, Proteomic, Metabolite and Photosynthetic Study

“…Overlaid DL and HL cell wall FTIR spectra are shown in Figure 8. The bands related to cellulose, such as a symmetric CH 2 vibration at 1416 cm −1 , CH 2 bending vibration at 1368 cm −1 , CH 2 wagging vibration at 1320 cm −1 , O-C-O asymmetric stretching glycosidic link vibration at 1147 cm −1 , C-OH stretching secondary alcohol vibration at 1052 cm −1 , C-OH stretching primary alcohol at 1029 cm −1 , and C-C stretching (C6-H2-O6) at 990 cm −1 were found in both cell wall samples (references are given in [22]). The bands at 1733 cm −1 (C=O stretching vibration of alkyl ester), 1611 cm −1 (COOantisymmetric stretching vibration of polygalacturonic acid), 1420 cm −1 (COOstretching), 1260 and 1236 cm −1 (C-O stretching), 1097 cm −1 (C-O and C-C stretching), 1017 cm −1 (C-O, C-C stretching, e.g., C 2 -C 3 , C 2 -O 2 , C 1 -O 1 ), 955 cm −1 (CO bending), 822 cm −1 (ring vibration), are characteristic for pectin.…”