Two sibling species of the Botrytis cinerea complex, transposa and vacuma,are found in sympatry on numerous host plants

Strains of Botrytis cinerea (the anamorph of Botryotinia fuckeliana) were c ollected from 21 different plant species around vineyards in the Champagne region (France). Strains were analyzed using three new polymerase chain rea ction (PCR)-restriction fragment length polymorphism (RFLP) markers that we re found by SWAPP (sequencing with arbitrary primer pairs), in addition to 15 other markers (PCR-RFLP, transposable elements, and resistance to fungic ides). The markers revealed a high degree of genetic diversity and were use d to investigate population structure. The two sympatric species transposa and vacuma, previously identified on grapes in these vineyards, were also d etected on many of the plant species sampled. A new type of strain was also detected, having only the transposable element Boty. We did not detect any differentiation between strains from different organs or locations, but th e prevalences of transposa and vacuma were significantly different on the d ifferent host plants. Fungicide resistance frequencies were significantly d ifferent in transposa and vacuma species. This study confirms that B. ciner ea is a complex of sibling species and shows that the sibling species occur sympatrically on many host plants. However, the two species seemed to have different pathogenic behaviors. These findings contradict the traditional view of B. cinerea as a clonal population without specialization.