Biological control of<i>Meloidogyne incognita</i>on cucurbitaceous crops by the non-pathogenic endophytic fungus<i>Fusarium oxysporum</i>strain 162

Abstract

Dual inoculation of the mutualistic endophytic fungus Fusarium oxysporum strain 162 (Fo162) applied at 1 × 106 colony-forming units/g of soil, first at sowing and then at transplanting, reduced early root penetration of Meloidogyne incognita race 3 in squash and melon up to 69 and 73%, respectively, compared to the untreated control which had over 250 nematodes per root system. Re-isolation of Fo162 from roots of squash was 28% and melon 27%. The colonization in melon was higher in the upper root zone than in the other two root portions (middle and lower root zones). In contrast, there was no fungal colonization preference among the three root zones investigated in squash. The fresh shoot weight of treated squash with Fo162 was higher than in the untreated control, whereas endophyte treatment did not affect fresh root weight. In melon there were no significant effects on plant growth. In conclusion, the results showed that the biocontrol activity of Fo162 against plant parasitic nematodes is not limited to plants of specific families, and that it has the potential to be used in cucurbitaceous crops such as squash and melon.