【目的】探索过氧化物酶体增殖剂(Peroxisome proliferators,PPs)对稻瘟病菌生长发育及致病性的影响。【方法】在6种不同的PPs诱导下,观察比较稻瘟病菌过氧化物酶体数量及相关基因表达、生长速率、孢子萌发、附着胞形成与致病性的差异。【结果】在不同的PPs诱导下,稻瘟病菌过氧化物酶体数量均呈现明显的增加,同时过氧化物酶体形成相关基因PEX8、PEX11、PEX14的表达量升高;PPs影响病菌菌丝生长、分生孢子萌发及附着孢形成,并导致致病性的减弱。其中,2,4-D与阿司匹林的抑制效果最为显著。同时,2,4-D与ASA对稻瘟病菌过氧化物酶体形成突变体Δpex5和Δpex7的生长抑制效果与野生菌株相比明显增加。【结论】首次将PPs类化合物用于模式丝状病原真菌稻瘟病菌的研究。研究发现6种PPs均能够引起过氧化物酶体的增殖,并可抑制稻瘟病菌生长发育,降低致病性。
[Objective] To study the effect ofperoxisome proliferations (PPs) on the development and pathogenicity of rice blast fungus Magnaporthe oryzae. [Methods] The peroxisomal proliferation and the expression of peroxisomal biogenesis related genes were detected in M. oryzae strain Guy11 under the induction of 6 PPs. Vegetative growth, conidial germination, appressoria formation and pathogenicity of the strain treated with PPs were compared with those of the control. [Results] Induced by 6 PPs, the quantity ofperoxisome and the expression ofPEX14, PEX8 and PEX11 were significantly increased. Vegetative growth, conidial germination, appressorial formation and pathogenicity were inhibited by the majority of the PPs. Of them, 2, 4-D and aspirin (ASA) exhibited higher inhibition rates than others. Further, the inhibition of 2, 4-D and Aspirin to the vegetative growth of Apex5 and Apex7 mutants of M. oryzae was found significantly increased than that of the wild type strain. [Conclusion] PPs could induce peroxisome proliferation in M. oryzae, inhibit the growth and development and reduce the pathogenicity of the fungus. This is the first investigation on the effects of PPs to filamentous fungi.