Abreu Fernanda Raquel Martins, Dedicova Beata, Vianello Rosana Pereira, Lanna Anna Cristina, de Oliveira João Augusto Vieira, Vieira Ariadna Faria, Morais Odilon Peixoto, Mendonça João Antônio, Brondani Claudio
Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiânia, Goiás, Brasil.
International Center for Tropical Agriculture A.A. 6713, Cali, Colombia.
Protoplasma. 2018 Nov;255(6):1751-1761. doi: 10.1007/s00709-018-1265-6. Epub 2018 May 30.
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.
这项工作旨在评估过表达水稻磷脂酶Dα1（OsPLDα1）基因的BRSMG Curinga品种转化植株的耐旱性。在一项实验中，对OsPLDα1基因独立转化事件植株的生产力进行了评估，该实验在生殖阶段施加了19天的水分亏缺，这对旱稻来说是非常严格的生长条件。干旱处理下的非转基因品种（NGM）与灌溉处理相比，生产力降低了89%，而转化植株（PLDα1_E2）生产力仅降低了41%。干旱处理后，PLDα1_E2植株的生产力是NGM植株的五倍。此外，未观察到对转基因植株生长发育的不利影响。恢复灌溉7天后，PLDα1_E2植株的气孔导度、光合速率和蒸腾速率均高于NGM植株，且OsPLDα1基因的表达水平也更高。在这些PLDα1_E2植株中观察到衰老过程延迟，这被确定为光合作用恢复的原因，其中Rubisco的表达量更高，SOD的表达量更低。这一发现表明氧化应激降低，可能是由于这些转化植株的气孔部分关闭导致气体交换，从而阻止了活性氧的形成。OsPLDα1基因的过表达导致在严重水分亏缺下产量损失减少，并揭示了培育更耐受极端干旱条件的旱稻品种的可能性。
