In phytopathogenic fungi, a mutation in the avirulence gene can lead to the breakdown of resistance in the host plant. The nucleotide sequences of the AVR-Pik locus in the strain Ina168 and its spontaneous mutant Ina168m95-5 of Pyricularia oryzae were determined. An AVR-Pik spontaneous deletion mechanism of Ina168m95-5, including multiple homologous recombination events involving repetitive transposable elements, is proposed.

中文翻译：

---

稻瘟病菌中 AVR-Pik 基因座的表征和提出的自发缺失机制。

在植物病原真菌中，无毒基因的突变会导致宿主植物的抗性崩溃。确定了稻瘟病菌 Ina168 及其自发突变体 Ina168m95-5 中 AVR-Pik 基因座的核苷酸序列。提出了 Ina168m95-5 的 AVR-Pik 自发缺失机制，包括涉及重复转座元件的多个同源重组事件。