tˈɛstɪŋ fɚðə pɹˈɛzəns ʌv nˈuː ɹᵻsˈɪstəns fˈæktɚz ɪz kəndˈʌktᵻd baɪ skɹˈiːnɪŋ sˈæmpəlz ʌv ˈɛl. sˌɛɹɪˈoʊlə wɪð vˈɛɹiəs ˈaɪsəlˌeɪts ʌv bˈiː. lˈæktuːkˌiː.
Testing for the presence of new resistance factors is conducted by screening samples of L. serriola with various isolates of B. lactucae.