Phytonematodes Associated with Kenaf (Hibiscus cannabinus L.) in Southwest Nigeria

The study identified the plant-parasitic nematodes associated with kenaf in selected loca-tions in southwest Nigeria. A survey was conducted in kenaf fields in Ile-Ife and Ikenne, Ibadan and Ilora in September,2022. The soil sampling procedure involved the collection of samples from 30 distinct locations proximate to the plant roots. Plant-parasitic nema-todes(PPNs)were extracted, identified and counted. The frequency of occurrence (FO) and population densities (PD) of the extracted nematodes were calculated. Four genera of PPNswere associated with kenaf in all study locations. These were Meloidogyne, Pratylen-chus, Helicotylenchus, and Tylenchus.In Ile-Ife, Meloidogynehad the highest population density per 200 ml soil (72.7%), followed by Helicotylenchus (21.4%),while the lowest den-sity was recorded for Tylenchus(2.0%). In Ikenne, the highest density was recorded for Meloidogyne(47.3%), followed by Pratylenchus (27.9%), and Helicotylenchus(24.4%). The lowest nematode density was recorded for Tylenchus(0.5%). In Ilora, the highest density was recorded for Meloidogyne(66.9%), followed by Helicotylenchus(23.9%), while the low-est density was recorded for Tylenchus(1.4%). The survey in Ibadan showed that nema-tode with the highest density was Meloidogyne(61.1%), followed by Helicotylenchus(28.0%),while the least density was recorded for Tylenchus (1.3%). This study concluded that four genera of PPN were associated with kenaf in Ikenne, Ile-Ife, Ilora and Ibadan. These were Meloidogyne, Helicotylenchus, Pratylenchusand Tylenchus. The most abun-dant was Meloidogyne. Therefore, in the management of PPN genera that may impact ke-naf production in southwest Nigeria in kenaf, more emphasis should be placed on root-knot nematodes.