The insecticidal efficacy of Gmelina arborea L. product extracts was assayed for suitability in controlling the legume pod borer Maruca vitrata Fab. (Lepidoptera: Pyralidae) and the pod sucking bug Clavigralla tomentosicollis Stäl (Hemiptera: Coreidae) on cowpea. Field studies conducted in 1999 and 2000 cropping seasons at the research farm of the Institute for Agricultural Research, Samaru showed that extract of Gmelina arborea fruit at 10% (w/v) caused impressive reduction ofboth pests and protected the pods from serious damage. Grain yield was higher in the fruit extract treated plants compared to the leaf, bark treatments and the untreated control. However, all the Gmelina products’ extracts were superior (p < 0.05) to the untreated control but was not better than the synthetic insecticide (Sherpa Plus) used in all the assessments made. This study is the first reported case ofthe potential of Gmelina arborea products’ extracts for control of Maruca pod borer larvae and pod sucking bug on field cowpea. This plant could add to the pool of herbal landraces already found to be insecticidal to insect pests of tropical crops if explored and exploited for use by limited resource farmers in tropical countries.

Three plant extracts viz. bulbs of Allium sativum L. (Liliaceae), seeds of Annona squamosa L. (Annonaceae) and leaves of Vitex negundo L. (Verbenaceae) were evaluated against cowpea wilt pathogen, Fusarium oxysporum f. sp. ciceris by mycelial dry weight method under laboratory condtions. The mean mycelium dry weights of F. oxysporum of methanol and benzene extracts of A. sativum obtained from 125 g of crused dry plant material (bulbs) were 0.0113 and 0.0174 mg, respectively. This was followed by methanol and petroleum ether extracts of A. squamosa (0.2396 and 0.2381 mg). They effectively controlled mycelial growth of cowpea wilt pathogen, however V. negundo extracts did not cause any significant mycelium growth inhibition when compared to other plant extracts tested. Among the three plant extracts, methanol extracts of A. sativum bulbs could possibly be used for controlling F. oxysporum.