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E. Eb-biotop, . Eb-koppert, and . Eb-biobest,

, S2 Native (EB-INRA87

. Eb-inra87,

. Eb-inra06, . Eb-biotop, and . Eb-biobest,

, S3 Native (EB-INRA87

E. Eb-biotop and . Eb-koppert,

, S4 Native (EB-INRA87

. Eb-inra87-(eb-biotop, . Eb-koppert, and . Eb-biobest,

, S5 Native (EB-INRA87

. Eb-inra87,

. Eb-inra06, . Eb-koppert, and . Eb-biobest,

, S6 Native (EB-INRA87

. Eb-inra87,

. Eb-inra06 and . Eb-biotop,

, S7 Native (EB-INRA87, EB-INRA06

. Eb-inra87,

. Eb-biotop,

, S8 Native (EB-INRA87, EB-Biotop

. Eb-inra87,

. Eb-inra06 and . Eb-biobest,

, S9 Native (EB-INRA87, EB-INRA06

. Eb-inra87,

. Eb-biotop and . Eb-koppert,

, S10 Native (EB-INRA87, EB-Biotop

. Eb-inra87,

. Eb-inra06 and . Eb-koppert,

, S11 Native (EB-INRA87, EB-INRA06

. Eb-inra87,

. Eb-koppert,

, S12 Native (EB-INRA87, EB-INRA06, EB-Koppert

. Eb-inra87, S13 Native (EB-INRA87, EB-Biotop

. Eb-inra87,

. Eb-inra87, . Eb-inra06, . Eb-biotop, and . Eb-koppert, S15 Native (EB-INRA87, EB-INRA06, EB-Biotop

. Eb-inra87,

. Eb-inra06 and . Eb-biotop,

, S17 Native (EB-INRA87

. Eb-inra87,

. Eb-koppert, EB-Biobest

, S18 Native (EB-INRA87, EB-INRA06, EB-Biotop

, For formal assessment of the relationship between the European biocontrol populations, we used ABC to compare 18 competing scenarios representing of a gradient from a scenario of full dependence (i.e. all samples derived from the 1982 INRA population: S1) to a scenario of full independence (i.e. all samples independently collected within the native area: S18). For instance, in scenario S3, the biocontrol populations EB-INRA87 and EB-Koppert were independently collected from the native area and all three biocontrol populations EB-INRA06, EB-Biotop and EB-Koppert originate from the same biocontrol population, Table S5: ABC analyses to assess the relationship between the five European Biocontrol populations