Appraisal of Moringa oleifera crude proteins for the control of root-knot nematode, Meloidogyne incognita in banana

Root-knot nematodes (RNKs) are injurious plant pests that have been managed mainly by synthetic nematicides. Regardless of their effectiveness, chemical nematicides can be deleterious to the environment and human health. The objective of this study was to assess the ecofriendly nematicidal properties of different crude protein extracts precipitated from Moringa oleifera seeds against the RNK, Meloidogyne incognita, on banana cv. Grande-Naine plants, in comparison with a biological control mean (Azotobacter chroococcum), a marine algae (Ulva lactuca), and a synthetic nematicide (Nemacur 10% G). Various ammonium sulfate concentrations were employed in the fractionation of proteins from M. oleifera. Different ammonium sulfate saturations (50, 60 and 70%) were used to obtain the first, second and third precipitate fractions (PFs), respectively. The in vivo test showed that the first PF gave the greatest reduction in number of nematode juveniles in soil (63.51%) and galls on roots (73.24%). Furthermore, these treatments and the marine algae increased plant growth more than the other tested materials. However, the effects on plant growth did not seem to be related with nematode control. PFs were tested for lectin hemagglutination using a microscopy. Hence, the first PF was the best fraction for the control of the nematode.