Influence of Meloidogyne incognita on Fusarium Wilt of Tomato at or below the Minimum Temperature for Wilt Development


  • J. J. Morrell
  • J. R. Bloom


'Bonny Best' tomato plants were grown at 16, 21, or 24 C for 28 d in soil infested with either of two isolates of Fusarium oxysporum f. sp. lycopersici race 1 and Meloidogyne incognita. Significant levels of fusarium wilt occurred at all temperatures including 16 C, which has not been reported previously. One Fusarium isolate resulted in the highest levels of disease incidence at 21 and 24 C in the presence of root-knot nematodes, and at 24 C when the nematodes were not present. At 16 C there was no significant difference in the number of plants infected by the second Fusarium isolate alone or in combination with root knot nematodes, although the presence of nematodes resulted in a significant increase in the percentage of disease occurrence and vessel infection at 21 C. Key words: root-knot, Fusarium oxysporum f. sp. lycopersici race 1, Lycopersicon esculentum.