Distribution of Plant-Parasitic Nematodes Associated with Tea in Nigeria

Several species of plant parasitic nematodes have been encountered in tea soils in different tea-growing areas of the world. Roots and soil were sampled for the presence of plant-parasitic nematodes from tea plantations in Kusuku, the only major tea growing location in Nigeria. Six genera and species of plant-parasitic nematodes were recovered from the rhizosphere soil. Meloidogyne spp., Pratylenchus coffeae and Helicotylenchus coffeae were predominant with prominence values of 380, 212 and 88, respectively and occurred in 84, 63 and 58% of all soil samples per 250 cm soil, respectively. This was followed in a descending 3 order, by Rotylenchulus reniformis, Radopholus spp. and Xiphenema spp. with frequency of occurrence of 43, 39 and 29, respectively. Meloidogyne spp. were the only nematode genus recovered from the sampled tea roots with 21% frequency of occurrence. Root-knot nematodes, Meloidogyne incognita significantly (P 0.05) reduced the leaf area of selected tea clones seedlings compared to the controls 24 weeks after inoculation. This nematode reproduced successfully on all the tea clones, but China clones exhibited some level of infection to the nematode. There is the need for concerted effort to control this nematode on tea, most especially with the recent occurrence in Nigeria to cultivate tea in the lowland.