Fusarium wilt, caused by Fusarium oxysporum f.sp. momordicae (FOM), is a major constraint to bitter gourd (Momordica charantia L.) cultivation in Taiwan. No Fusarium wilt-resistant bitter gourd is commercially available, so far. Bitter gourd is commonly grafted to pumpkin or other cucurbit rootstocks in Taiwan. This is becoming less effective as wilting is now observed in grafted plants. FOM is not host specific and there is concern that FOM can be cross-infective to the cucurbit rootstocks.