In some cases, wild species are the primary source of resistance traits; some tomato cultivars that have gained resistance to at least 19 diseases did so through crossing with wild populations of tomatoes.
ɪn sˌʌm kˈeɪsᵻz, wˈaɪld spˈiːsiːz ɑːɹ ðə pɹˈaɪmɚɹi sˈoːɹs ʌv ɹᵻsˈɪstəns tɹˈeɪts; sˌʌm təmˈeɪɾoʊ kˈʌltɪvˌɑːɹz ðæt hæv ɡˈeɪnd ɹᵻsˈɪstəns tʊ æt lˈiːst nˈaɪntiːn dɪzˈiːzᵻz dˈɪd sˌoʊ θɹuː kɹˈɔsɪŋ wɪð wˈaɪld pˌɑːpjʊlˈeɪʃənz ʌv təmˈeɪɾoʊz.