As the unseen enemy, nematodes have caused untold damage to crops and farmers’ income across the world. A study was conducted in 2019 and 2020 to determine the effect of leaf extract and powder of Ipomoea asarifolia (Desr.) Roem. & Schult. On root-knot nematode (Meloidogyne javanica) (Treub, 1885) on okra in the laboratory and pot experiment. Juvenile mortality and egg hatch inhibition tests were conducted in the laboratory. Result of the juvenile mortality test showed that the crude extract (100 % extract) cause the highest mortality (95.33 %) of juveniles while the same crude extract inhibited the hatching of more M. javanica eggs (89.67 %) than the dilutions and control. For the pot experiment, results show that the 60 g powder treatment gave the least galling index (1.0), nematode population (146.96), reproduction factor (0.25) and the highest yield (1568.3 Kg/ha) in 2019. The same trend was observed in 2020. Based on these findings, I. asarifolia leaf extract and powder (60 g) have the potential to put in check the menace posed by M. javanica on okra.

Extracts of Piliostigma thonningii were tested for their effectiveness in controlling Meloidogyne javanica eggs and juveniles in the laboratory and on eggplant cv ‘Yalon Data’. A thousand juveniles were placed in 12 petridishes and extracts of P.  thonningii (Crude extracts, 5 ml dilution and 10 ml dilution of the crude extracts) were dispensed into the petridishes. One thousand eggs of the M. javanica were placed in 12 petridishes and treated with the same extracts used on the juveniles. For the field experiment, 12 plots of size 2m x2m were prepared and planted with nine plants of eggplant cv ‘Yalon Data’. Seedlings of eggplants were transplanted after three weeks in the nursery to the field into holes drenched with 10 ml of the extracts used in the laboratory tests. Subsequent applications of extracts were done weekly for eight weeks. The results showed that the crude extract was the most effective against both the eggs (87.43 % hatch inhibition) and juveniles (90.23 % mortality). In the field, eggplants treated with the crude extract recorded the tallest plants ((124.78 cm -2017 and 125.00 cm-2018), highest number of fruits/plant (18.51-2017 and 19.55-2018), highest yield (50.45t/ha-2017 and 53.78t/ha-2018) and the lowest galling indices and final nematode population. It is therefore concluded that the crude extract of P.  thonningii can be employed for the control of M. javanica in the field.