Incidence of Sitophilus oryzae and other stored-product pests on cowpea in local markets in Accra: management strategies employed by retailers.

In recent times, the unusual presence of Sitophilus on cowpea has become an issue in Ghana as it constitutes a threat to food sufficiency and food security; this, by extension, necessitated the execution of this survey to establish the specific identity of the insect and its incidence, on stored cowpea in Ghana and consequently assess the level of awareness of traders and the management strategies employed. Using internal morphological identification techniques, the insect was identified as Sitophilus oryzae with an incidence rate of 12, 22 and 20% as against 50, 41 and 42% incidence rate of Callosobruchus maculatus after 30, 60 and 90 days respectively, of undisturbed storage of cowpea within the marketing systems in Accra, Ghana. Relatively low number of retailers (35.44%, N = 79) was aware of this occurrence, with 91.14% of this employing the energy-demanding and time-consuming sieving techniques as their main control strategies. This paper draws attention to the possible worsening of food insecurity already eminent in Africa for insects are no respecters of international or geo-political boundaries as they can spread to other countries, should this observation be left unchecked.

Volatile infochemicals used in host and host habitat location byCotesia flavipes Cameron andCotesia sesamiae (Cameron) (Hymenoptera: Braconidae), larval parasitoids of stemborers on graminae.

FemaleCotesia flavipes Cameron andCotesia sesamiae (Cameron) were attracted to odors in a Y-tube olfactometer from uninfested maize (Zea mays L.), sorghum [Sorghum bicolor (L.)], and napier grass (Pennisetum purpureum Schumach). In dual choice tests,Cotesia flavipes showed a preference for maize over sorghum, while maize and napier grass were equally attractive. In contrast,Cotesia sesamiae preferred volatiles from sorghum and napier grass over those from maize. The two parasitoids were significantly more attracted to maize infested with the stemborers,Chilo partellus (Swinhoe),Chilo orichalcociliellus Strand,Sesamia calamistis Hampson, andBusseola fusca (Fuller), than uninfested maize. In dual choice tests,Cotesia flavipes andCotesia sesamiae were unable to discriminate between odors from plants infested by the different species of stemborers.