为探明印度梨形孢对烟草抗旱性的影响,采用聚乙二醇(PEG 6000)人工模拟干旱胁迫条件进行盆栽试验.在干旱胁迫下,测定了烟叶中丙二醛(MDA)和脯氨酸(Pro)的含量、叶片相对电导率以及干旱相关基因的表达量.结果表明:印度梨形孢能定殖于烟草根部,并促进烟草地上部和地下部的生长.在干旱条件下,根部接种印度梨形孢的烟草缺水症状较轻,与未接种印度梨形孢的烟草相比,其烟叶中Pro含量显著升高,MDA含量和叶片相对电导率显著下降,干旱相关基因RD29A、ERD10A、RD26A、SDIR1、HAT、ERD1和DREB2A的表达量均明显上升.印度梨形孢提高烟草的抗旱能力,是通过降低烟草细胞生物膜的损伤程度、增强烟草的抗氧化防御能力、促进细胞渗透调节物质Pro的积累以及上调干旱胁迫相关基因的表达实现的.%To investigate the effect of Piriformospora indica on drought resistance of Nicotiana tabacum, a pot experiment was conducted by using polyethylene glycol (PEG) 6000 to simulate drought and the malondialdehyde (MDA) and proline contents, relative electrical conductivity and expression levels of drought-related genes in tobacco leaves under drought stress were analyzed. The results showed that P. indica could colonize in the roots of N. tabacum and promote the growth of both root and shoot of the plants. When P. indica-inoculated plants were under drought stress, the symptoms of water shortage were slighter, the proline content in leaves was significantly up-regulated, while the MDA content and relative electrical conductivity of leaves were significantly decreased comparing with those of un-colonized treatment. Quantitative real-time polymerase chain reaction (qRT-PCR) analysis indicated that the relative expression levels of drought-related genes RD29A, ERD10A, RD26A, SDIR1, HAT, ERD1 and DREB2A were higher in leaves of colonized plants under drought stress. P. indica enhances the drought resistance of N. tabacum via reducing tobacco cell biological membrane damage degree, enhancing the antioxidant ability of tobacco, promoting the accumulation of osmotic substances proline and up-regulating the expression of drought-related genes.
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