Researchers at the University of Florida have identified new species of nematodes that are harming the roots of tropical fruits such as pitahaya, guava, and passion fruit. These nematodes, which live in the soil, can cause yellowing of leaves, stunting of trees, and crop failure, and have not been previously identified by growers. The team, led by Abolfazl Hajihassani, has identified two root-knot nematode species, Meloidogyne enterolobii and Meloidogyne incognita, in guava and passion fruit orchards, respectively. These findings are crucial in developing control methods to protect these high-value crops and improving the sustainability of tropical fruit production in Florida. The researchers are also exploring the resistance of different cultivars and genotypes of guava and passion fruit to these nematodes, and looking for indigenous microbial agents for biological control.