IOSR Journal of Environmental Science, Toxicology and Food Technology (IOSR-JESTFT) e-ISSN: 2319-2402,p- ISSN: 2319-2399.Volume 8, Issue 9 Ver. III (Sep. 2014), PP 25-31 www.iosrjournals.org www.iosrjournals.org 25 | Page Nematode Damage to Plantain (Musa spp. AAB-Group) at Flowering as Affected by Paring and Organic Mulch in South- western Nigeria M. Omolara Olaniyi 1 Biology Programme, School of Science and Technology, National Open University of Nigeria, P.M.B. 80067 Victoria Island, Lagos. Abstract: The experiment investigated the effects of paring, oil palm bunch refuse and sawdust mulches on the flowering of mother plant, development of suckers, and the establishment, population and damage dynamics of plant parasitic nematodes on plantain cultivar Agbagba in Southwestern Nigeria. A multifactorial experiment was laid out in a randomized complete block design. Above-ground plant growth parameters were measured at flowering of mother plants. Twenty-two months after planting (MAP), mats were sampled to assess nematode population densities, root and rhizome damages. Results of this study showed that paring and mulching gave complementarily effect on early flowering of plants, improved root production and the extent of benefit was dependent on the type of mulch material used. Pared plants produced fewer suckers at flowering than the non- pared plants, had healthier roots and lower root infections associated with plant parasitic nematode damage. Oil palm bunch refuse was superior to the sawdust mulch in enhancing plant growth, root health and suppressing nematode population densities. In an integrated pest management context therefore, paring coupled with mulching is recommended to boost plantain production. Keywords: Agbagba, plant growth, paring, plant parasitic nematodes, plantain, root health I. Introduction Plant parasitic nematodes associated with plantain damage in Nigeria include Helicotylenchus dihystera, multicinctus, Meloidogyne spp, Pratylenchus coffeae and Radopholus similis. Of these, P. coffeae was classified as the most serious closely followed by R. similis relative to association with root and plant damage indices and the nematodes were reported to cause 30% loss in Nigeria (Speijer et al., 2001). The authors also established that R. similis was prevalent in Southeastern Nigeria while in southwestern Nigeria it was P. coffeae that predominates. Subsequently, Rotimi et al. (2004a & b) investigated the extent of yield loss to plantain as a result of nematode damage in Southeastern Nigeria and recorded between 46% and 54% yield reduction from R. similis and a complex of other associated plant parasitic nematodes but without P. coffeae. The authors noted that the extent of loss was dependent on the genotype planted, soil fertility status and management. Similarly in line with the observations of Speijer et al. (2001) with the Nigeria average, Rotimi et al., (2004b) further noted that R. similis related loss could be about 33% absolute yield loss due to toppling of plant bearing immature bunches. It is not known however, the extent of yield loss possible with P. coffeae in association with other less damaging species in Nigeria. Since P. coffeae is ranked the most damaging species in Nigeria and predominant in the Southwest, it is necessary to site trials in that location in order to be able to access the damage potential of the species. Effective management of these nematodes would improve production and increase longevity of plantain plantation. Suitable agronomic practices which reduce the loss to pathogens and address soil fertility depletion are required as poor soil fertility aggravates pests and diseases symptoms thereby increasing the cost of management. Mulching is also reputed to mitigate the impact of plant parasitic nematodes on plantain (Rotimi et al., 2004a & b) especially when applied to low fertility systems (McIntyre et al., 2000). The relevance of organic mulch to soil management and it influence on the plant growth cannot be overemphasized. Organic mulch, like crop residues, has been used in gardens, plantation crops and arable crops for centuries to add organic matter to the soil and do smother weeds (Akobundu, 1987). Mulching is reported to enhance plantain growth rate, support better sucker production and produce more leaves with larger areas (Rotimi et al., 2004b). The investigators noted that organic mulch maintained more favorable physical and chemical soil condition than unmulched treatments. Other benefits of mulching are that mulch protects soil from 1 The study was undertaken when author was with the Department of Crop, Soil and Pest Management, School of Agriculture and Agricultural Technology, Federal University of Technology, P.M.B. 704 Akure, Ondo State, Nigeria.