Overexpression of a phospholipase (OsPLDα1) for drought tolerance in upland rice (Oryza sativa L.)

Abstract

This work aimed to evaluate the drought tolerance of transformed plants of the cultivar BRSMG Curinga that overexpress the rice phospholipase D α1 (OsPLDα1) gene. The productivity of independent transformation event plants of the OsPLDα1 gene was evaluated in an experiment where 19 days of water deficit were applied at the reproductive stage, a very strict growing condition for upland rice. The non-genetically modified cultivar (NGM) under drought treatment reduced productivity by 89% compared with that under irrigated treatment, whereas transformed plants (PLDα1_E2) reduced productivity by only 41%. After the drought treatment, the PLDα1_E2 plants productivity was five times greater than that of the NGM plant. Moreover, no adverse effects on growth and development of the transgenic plants were observed. Seven days after the resumption of irrigation, PLDα1_E2 plants had higher stomatal conductance, greater photosynthetic rate, and transpiration rate than did NGM plants, as well as a higher expression level of the OsPLDα1 gene. A delay in the senescence process was observed in these PLDα1_E2 plants, and this was determined for the recovery of photosynthesis, with greater expression of the Rubisco and lower expression of the SOD. This finding was suggestive of decreased oxidative stress, probably due to gas exchange by the partial closure of the stomata of these transformed plants, which prevented the formation of reactive oxygen species. OsPLDα1 gene overexpression resulted in a reduction in production loss under severe water deficit and revealed a possibility for the development of upland rice cultivars that are more tolerant to extreme drought conditions.

Role of DNA methylation dynamics in desiccation and salinity stress responses in rice cultivars

“…It has been shown that over-expression of chymotrypsin inhibitor-like 1 ( OsCPI1 ) in rice resulted in better survival and higher seed yield under severe drought (Huang et al ., 2007). The role of phospholipase in eliciting drought tolerance via modulating calcium-signalling pathway has also been demonstrated in rice (Abreu et al ., 2018; Deng et al ., 2019). These results suggest that hypomethylation in CHH context may govern regulation of candidate genes involved in desiccation stress response in Nagina 22.…”

Phospholipase Dα6 and phosphatidic acid regulate gibberellin signaling in rice

“…In addition, OsPLDα1 affects cold stress response through its product PA regulating the expression of OsDREB1 (Huo et al , 2016). Overexpression of PLDα1 in upland rice improved drought tolerance by maintaining the photosynthetic apparatus integrity (Abreu et al , 2018). Two chloroplast‐localized PLDs, OsPLDα4 and OsPLDα5, regulate herbivore‐induced direct and indirect defenses (Qi et al , 2011).…”

Mutational Analysis of OsPLDα1 Reveals Its Involvement in Phytic Acid Biosynthesis in Rice Grains

“…In recent years, PLD has been reported to be involved in several plant cellular processes, playing a significant role in seed germination, pollen tube development, and root hairs growth . Furthermore, PLD is directly involved in plant stress responses; for instance, AtPLDα1 regulates the abscisic acid (ABA) signaling, and overexpression of OsPLDα1 induces drought tolerance in rice . The suppression of PLDα1 in Arabidopsis enhances freezing tolerance, while suppression of PLDγ increases susceptibility to cold stress; these results indicate that each individual PLD gene could play a distinct role in response to plant stress.…”