EFFECTS OF SELECTED ANIMAL MANURES ON PLANT - PARASITIC NEMATODES INFECTING YAM SPECIES

Field study was conducted in 2016 and 2017 to investigate the potency of animal manures on phytonematodes infecting yam species (Dioscorea rotundata and D. alata). Nematode infested fields were prepared into plots of 2 m. Dried cow, poultry and swine manure were incorporated into each plot at the rate of 5 tons / hectare and 10 tons / ha immediately after land preparation while seed yam of 100-150 gm were planted into each heap two weeks later. There were fourteen treatments including control replicated four times in a 2 x 7 factorial experiments fitted into a randomized complete block design (RCBD). Data collected include; nematode populations, weight of yam at harvest, total nitrogen, available phosphorous (P), exchangeable potassium (K) and soil pH. The results of the study revealed that the incorporation of dried and decomposed poultry, cow and swine manure both at lower and higher rates (5 tons / ha and 10 tons / ha) each reduced populations of the plant-parasitic nematodes and increased the yields of the two yam species. The results of this study therefore revealed that application of the amendments in a field infested with nematodes has the potentials for managing nematode population and nematode damage on D. rotundata and D. alata.