Water deficit and recovery response of Medicago truncatula plants expressing the ELIP-like DSP22

Abstract

In this article, we present the response of Medicago truncatula Gaert. cv. Jemalong plants expressing constitutively the Dsp22 gene from Craterostigma plantagineum to water stress and rehydration. The Dsp22 gene encodes an ELIP-like protein thought to protect the chloroplast against photooxidative damage during the dehydration and rehydration. The Dsp22 transgenic homozygous M. truncatula plants showed higher amount of chlorophyll (Chl), lower Chl a/Chl b ratio and higher actual efficiency of energy conversion in photosystem 2 (Φ PSII ) after rehydration when compared to the wild type. The combined data from the Chl a fluorescence analysis, pigment quantification, and biomass accumulation showed that transgenic M. truncatula plants are able to recover from water deprivation better than wild type plants.

Performance index: An expeditious tool to screen for improved drought resistance in the Lathyrus genus

“…Because both absorption and trapping efficiency increase under water deficit, it is not surprising that the maximum quantum efficiency of PSII (F v /F m ) is only affected in severe WD. The resilience of the F v /F m parameter to WD was also previously described by us in Setaria sphacelata (Marques da Silva and Arrabaça 2004), M. truncatula (Nunes et al 2008;Araújo et al 2013), and Zea mays (Cruz de Carvalho et al 2011). Importantly, the grass pea genotypes L174-A and Raipur managed to keep high F v /F m values even under extreme WD.…”

“…Chlorophyll a (Chl a) fluorescence has been one of the most used techniques for providing rapid insights in the ability of a plant to tolerate environmental stresses (Baker and Rosenqvist 2004), like nitrogen starvation (Marques da Silva and Arrabaça 1992), WD (Cruz de Carvalho et al 2011;Araújo et al 2013), or frost adaptation (Ratinam et al 1994). Moreover, it allows understanding to what extent those stresses have damaged the photosynthetic apparatus and affected photosystem II (PSII) photochemical efficiency (Baker and Rosenqvist 2004).…”

Differential proteomics of dehydration and rehydration in bryophytes: evidence towards a common desiccation tolerance mechanism

“…In the last decades, researchers have directed their efforts towards the study of plants with improved water‐use efficiency (Khana & Hanjra ) and increased resistance to water deficits (Araújo et al . ), aiming to apply this knowledge to a biotechnology solution for crop plant improvement. Many traits that contribute to water deficit tolerance in plants (e.g.…”

Surviving metabolic arrest: photosynthesis during desiccation and rehydration in resurrection plants

“…The two final mechanisms by which HDT plants minimize ROS formation are downregulation of the synthesis of photosynthesis‐related gene products, such as rbcl, Chl a/b ‐binding protein, or oxygen‐evolving complex, and induction of protective proteins such as early light‐inducible proteins (ELIPs) …”

“…39 The two final mechanisms by which HDT plants minimize ROS formation are downregulation of the synthesis of photosynthesis-related gene products, such as rbcl, Chl a/b-binding protein, or oxygen-evolving complex, 15 and induction of protective proteins such as early light-inducible proteins (ELIPs). 34,40 In H. rhodopensis, the damage to the photosynthetic apparatus was limited to a repairable level, and the integrity was maintained in the dry state, enabling full recovery after rehydration. The lack of changes in both chlorophyll content and the amount of chlorophyll-binding proteins, together with the reversible modifications in PSII electron transport with changes in charge separation and stabilization of PSII and increased polyphenolic synthesis, contributes to desiccation tolerance in H. rhodopensis.…”