Cátedra de Química Biológica Vegetal, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires, Argentina.
Appl Microbiol Biotechnol. 2011 May;90(4):1389-97. doi: 10.1007/s00253-011-3162-1. Epub 2011 Mar 2.
The ability of two strains of Azospirillum brasilense to mitigate NaCl stress in barley plants was evaluated. Barley seedlings were inoculated and subjected to 200 mM NaCl for 18 days. Several days after NaCl treatment, a significant decline in biomass as well as in height was observed in uninoculated plants. However, smaller reductions in biomass and height were detected in plants inoculated with strain Az39. All the stressed plants showed significantly higher Na(+) but lower K(+) contents in their shoots. The growth rate of uninoculated plants was adversely affected by saline treatment, which was associated with higher putrescine content and lower levels of HvPIP2;1 transcripts in the roots. Azospirillum inoculation triggered the transcription of this gene. Our results suggest that barley plants inoculated with A. brasilense may be better prepared to thrive under saline conditions. To our knowledge, this is the first report showing an effect of Azospirillum inoculation on the expression of PIP2;1, a gene involved in the synthesis of root water channels.
评估了两株巴西固氮螺菌（Azospirillum brasilense）菌株缓解大麦植株盐胁迫的能力。将大麦幼苗接种并施加 200mM NaCl 处理 18 天。在 NaCl 处理数天后，未接种的植物的生物量和高度明显下降。然而，接种菌株 Az39 的植物的生物量和高度减少幅度较小。所有受胁迫的植物的地上部分的 Na(+)含量显著升高，而 K(+)含量降低。未接种植物的生长速度受到盐处理的不利影响，这与根系中腐胺含量升高和 HvPIP2;1 转录本水平降低有关。固氮螺菌的接种触发了该基因的转录。我们的结果表明，接种巴西固氮螺菌的大麦植物可能更能适应盐胁迫条件。据我们所知，这是首次报道固氮螺菌接种对参与合成根水通道的 PIP2;1 基因表达的影响。
