Parasitoid complex of fall armyworm, spodoptera frugiperda, in Ghana and Benin

Open Access Journal; Published online: 21 Jan 2020The fall armyworm, Spodoptera frugiperda, a moth originating from the American continent, has recently invaded most African countries, where it is seriously threatening food security as a pest of cereals. The current management methods rely heavily on the use of synthetic insecticides but there is a need for more sustainable control methods, including biological control. Surveys were conducted in two West African countries, Ghana and Benin, to determine the native parasitoid complex and assess parasitism rates of S. frugiperda. Samples of S. frugiperda eggs and larvae were collected in maize fields located in 56 and 90 localities of Ghana and Benin, respectively, from July 2018 to July 2019. Ten species were found parasitizing the pest, including two egg parasitoids, one egg–larval, five larval and two larval–pupal parasitoids. The two most abundant parasitoids in both countries were two Braconidae: the egg‐larval parasitoid Chelonus bifoveolatus and the larval parasitoid Coccygidum luteum. Parasitism rates were determined in three Ghanaian regions and averages varied from 0% to 75% between sites and from 5% to 38% between regions. These data provide an important baseline for the development of various biological control options. The two egg parasitoids, Telenomus remus and Trichogramma sp. can be used in augmentative biological control and investigations should be conducted to assess how cultural practices can enhance the action of the main parasitoids, C. luteum and Ch. bifoveolatus, in the field. Understanding the parasitoid complex of S. frugiperda in Africa is also necessary before any development of classical biological controls involving the introduction of parasitoids from the Americas

Black Soldier Fly (Hermitia illucens) Larvae Meal as Alternative Protein in Broiler Production in Ghana

Feed cost has been a major challenge to the competitiveness of the poultry industry of Ghana due mainly to high cost of proteins. Insect larvae meals seem convenient alternatives however their use on commercial scale is unknown in Ghana. Three 8-week feeding trial using three isonitrogenous, isocaloric diets in a three-phase feeding strategy involving 1320 broiler DOCs was conducted. BSFLM was used as replacement for fishmeal and as partial replacement for soybean meal to determine its effect on broiler productivity, profitability and carcass measurements. The results indicated that replacing fishmeal with BSFLM significantly improved weight gain, feed conversion efficiency and production efficiency factor (PEF). No detrimental effect was observed on carcass and specific organ measurements. Using the partial budgeting approach on a 500-bird estimation an increase of one thousand, one hundred and eleven Ghana cedis (GH₵1,111.00) was obtained when the fishmeal was replaced with BSFLM. Also, an increase of four hundred and sixty-seven Ghana cedis (GH₵467.00) was estimated when soybean meal was partially replaced with BSFLM. It was concluded that BSFLM can be used to improve the productivity and profitability of broiler production

Substrates most preferred for black soldier fly Hermetia illucens (L.) oviposition are not the most suitable for their larval development

Larvae of black soldier fly (BSF), Hermetia illucens (L.1758) (Diptera: Stratiomyidae), are increasingly being used as animal feed ingredients. Larvae are usually produced by placing eggs, obtained from adult rearing on growing substrates but can also be obtained by exposing substrates to naturally occurring BSF females. In the latter system, the substrate needs not only to be nutritious for the larvae but also attractive to the females for oviposition. The ‘preference-performance principle’ suggests that female insects prefer to oviposit in substrates that maximise offspring fitness. In this study conducted in Ghana, six organic substrates known to be suitable for BSF production were evaluated for their suitability as oviposition attractants and larval development: pito mash (waste from a locally brewed sorghum drink), millet porridge mash, pig manure, chicken manure, fruit waste, and waste from roots and tubers. These were first exposed outdoors to measure the quantity of eggs laid on them by naturally occurring BSF females. In a second experiment, the quality of the substrates as larval rearing media was tested by placing a standard amount of young larvae to measure the individual and total weights of prepupae obtained, their number, and their development time. The nutritional profiles of both the prepupae and the substrates were determined. The substrate used significantly influenced the quantity of eggs laid and the development of the resulting prepupae, but the substrates most favourable for larval development were not the most favoured by gravid BSF for oviposition. In the oviposition tests, millet porridge mash was the most attractive substrate, whereas only a few eggs were recovered from the other substrates. All substrates allowed the successful development of larvae but pig manure was more productive than the others