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Fusarium equiseti (Corda) Sacc., reported on cowpea (Vigna unguiculata (L.) Walp.) seeds in India (2), was isolated for the first time in Nigeria from naturally infected cowpea seeds. Cowpea, cv. IT90K-76, seeds (400) from plants grown in Nigeria were surface-disinfested in 0.05% NaOCl and placed on moist filter paper in petri dishes (10 seeds per dish) and then in a dark incubator for 4 days at 27°C. After incubation, some seeds had fungal mycelia growing on their surfaces. When cultured on potato dextrose (PDA) and Spezieller Nährstoffarmer (SNA) agars, the fungi produced macroconidia characteristic of F. equiseti (1). Septate macroconidia were three to six celled with extended apical and distinctive foot-shaped basal cells. F. equiseti was recovered from 4.25% of seeds, and incidence correlated positively with development of seed rot symptoms. To confirm pathogenicity, 80 cowpea seeds were surface-disinfested with NaOCl, and 40 were soaked for 6 h in a suspension of 3 × 105 conidia of F. equiseti per ml of water. The remaining seeds were soaked in sterile distilled water. After incubation, white mycelia developed on 87.5% of seeds soaked in the conidial suspension and rotted without germinating. Only 5% of seeds soaked in sterile water developed seed rot symptoms. When cultured on PDA and SNA, fungi isolated from artificially infested seeds with rot symptoms again were identified as F. equiseti. References: (1) P. E. Nelson et al. 1983. Fusarium species: An illustrated Manual for Identification. Pennsylvania University Press, University Park. (2) O. K. Sinha and M. N. Khare. Seed Sci. Technol. 5:721, 1977.

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Root-knot nematode,Meloidogyne incognita, is an important animate pathogen causing major damage and severe reductions in the growth, yield, and quality of sweet potato. Nematicides are expensive and their application also causes environmental pollution. A field experiment was therefore conducted to evaluate the effectiveness of poultry dung (10 or 20 t/ha), cow dung (10 or 20 t/ha), horse dung (10 or 20 t/ha), goat dung (10 or 20 t/ha), organomineral fertilizer (2 or 4 t/ha), and carbofuran (3 kg a.i/ha) in the management ofM. incognitaon sweet potato using a randomized complete block design. The unamended plots served as control. Data were analysed using ANOVA (p≤0.05). All organic materials and carbofuran significantly (p≤0.05) reduced nematode reproduction and root damage compared with control. Poultry dung (10 and 20 t/ha) and carbofuran were, however, more efficient in nematode control than other organic materials. Sweet potato plants that were grown on soil treated with organomineral fertilizer had the highest mean number of vines and fresh shoot weight, while poultry dung improved sweet potato quality and yield. It is therefore recommended that the use of poultry dung be employed in combination with other nematode control strategies to achieve sustainable, economic, and environment-friendly nematode management.