Effects of Tomato (Lycopersicon lycopersicum L.) seedlings root dip in Shea butter (Vitellaria paradoxa) bark extracts on root-knot nematodes (Meloidogyne javanica) infestation and tomato yield in Adamawa, Nigeria (Published)
Root-knot nematodes (Meloidogyne javanica) have been established to cause serious yield loss to crops worldwide and that of tomato in particular. Their control or management has been a problem lowered chemical control though successful are harmful to environment and human health and they are also costly to the resource poor farmers in Nigeria. Therefore, an experiment was set up to determine the efficacy of plant extracts which are easily broken down and could be less costly. A field experiment was conducted to test the efficacy of bark extracts of shea butter (Vitellaria paradoxa) on Meloidogyne javanica infestation on tomato using seedling root dips. The field experiments were laid out in a split plot design at Loko and Mayo Belwa locations, the two factors were concentration and time of exposure, four different concentrations (control, 10, 30 and 60%) and four different exposure periods (5, 15, 30 and 60 mins) making sixteen treatments replicated three times. Concentrations were assigned to main plot while exposure period allocated to subplots. Data were taken from the two locations on number of flowers, number of fruits, cumulative fruits weight (g), number of nematodes in 100g of soil and number of nematodes in 10g of roots. Data were analyzed using ANOVA and means were separated with Least Significant Difference (LSD) at 5% level of probability. The results of the field experiment at both Loko and Mayo Belwa location, showed that the root dip with 60% concentration exposed for 60 minutes in shea butter bark extracts recorded the highest number of flowers/plant 61.25 and 53.50 for concentration, 47.92 and 43.92 for duration at Loko and Mayo Belwa respectively. Number of fruits/plant 24.41 and 21.58 concentration and 17.33 and 15.08 duration, heaviest cumulative fruit weight/plant 2671.7 and 2461.6g concentration and 2320.3 and 2094.4g duration, nematode population in 100g of soil 372.4 and 461.3 concentration and (678.8 and 786.8 duration) and nematode population in 10g of roots/plant 124.2 and 189.9 concentration and 363.5 and 469.8 duration) at Loko and Mayo Belwa respectively. In conclusion, this study showed that V. paradoxa bark extracts was able to control M. javanica in the field as root dip. Therefore, this plant material has the potentials of replacing the environmental unfriendly and harmful nematicides found in the market today.