Abstract

The use of biochar has been shown to suppress populations of soil-borne pathogens. Hence it has been promoted as one of the eco-friendly alternatives to synthetic pesticides. In the current study, the effects of different sources of indigenous biochar on Meloidogyne incognita and overall growth and yield of tomato were evaluated under screenhouse condition in 2016 and 2017. A total of 10 treatments were evaluated in the study including tomato plants infected with 5000 infective juveniles of M. incognita treated with biochar woodchips of gum arabic (Acacia nilotica), bush mango (Irvingia gabonensis), neem (Azadirachta indica), goat head (Acanthospermun hispidum), gmelina (Gmelina arborea), locust bean (Parkia biglobosa), lagos mahogany (Khaya ivorensis), fig (Ficus sur), eucalyptus (Eucalyptus camaldulensis) and an untreated control. Treatments were laid-out in completely randomized design (CRD) and replicated four times. Data collected on nematode damage indices, plant height, number of leaves, and fruit yield/plant were subjected to analysis of variance. Means were separated using Duncan’s new multiple range test at 5% level of probability. Among all the biochar treatments evaluated, bush mango (BM) and neem (N) biochars significantly (p≤0.05) reduced root galling index (RGI), infective juveniles and final populations of M. incognita. In 2016 and 2017, the use of BM and N resulted in 64.05 and 66.52% reduction in galling, respectively while neem biochar reduced RGI by 66.49 and 70.76%, respectively and increased yield of tomato by 57.5%. Findings from this study have provided evidence that biochar formulated from indigenous woodchips in Nigeria, especially bush mango (Irvingia gabonensis) and neem (A. indica) are a promising tool in the control of M. incognita.

Key words: Biochar, tomato, Meloidogyne incognita, indigenous tree, Nigeria.