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Fall armyworm (FAW) was reported for the first time in Africa in 2016. FAW is widely distributed in Ethiopia, causing significant damage to maize. Nine synthetic insecticides belonging to different chemical groups and 11 pesticidal plants (botanicals) were tested for their efficacy against FAW under laboratory, greenhouse, and field conditions. In the laboratory, Radiant, Tracer, Karate, and Ampligo caused over 90% larval mortality 72 h after application. Malathion had moderate activity, causing 51.7% mortality 72 h after application, while Carbaryl was less effective, causing 28% mortality 72 h after application. In the greenhouse experiment, all synthetic insecticides reduced foliar damage to maize compared to the untreated control. Chemical sprays did not affect plant height, stem thickness, or leaf number. The highest fresh weight (471 g) was obtained from plants treated with Radiant. Among the botanicals tested, Azadirachta indica, Schinnus molle, and Phytolacca dodecandra resulted in the highest percentage larval mortality (>95%) 72 h after application. In the field, non-treated control plants showed extensive leaf injury compared to the synthetic insecticide- and botanical-treated plants. The synthetic insecticides and botanicals that showed high efficacy against FAW larvae can be used as components for integrated pest management (IPM) plans for FAW under smallholder farmer conditions in Ethiopia and elsewhere in Africa.

The fall armyworm (FAW), Spodoptera frugiperda, is a major pest of maize in North and South America. It was first reported from Africa in 2016 and currently established as a major invasive pest of maize. A survey was conducted to explore for natural enemies of the fall armyworm in Ethiopia, Kenya and Tanzania in 2017. Smallholder maize farms were randomly selected and surveyed in the three countries. Five different species of parasitoids were recovered from fall armyworm eggs and larvae, including four within the Hymenoptera and one Dipteran. These species are new associations with FAW and were never reported before from Africa, North and South America. In Ethiopia, Cotesia icipe was the dominant larval parasitoid with parasitism ranging from 33.8% to 45.3%, while in Kenya, the tachinid fly, Palexorista zonata, was the primary parasitoid with 12.5% parasitism. Charops ater and Coccygidium luteum were the most common parasitoids in Kenya and Tanzania with parasitism ranging from 6 to 12%, and 4 to 8.3%, respectively. Although fall armyworm has rapidly spread throughout these three countries, we were encouraged to see a reasonable level of biological control in place. This study is of paramount importance in designing a biological control program for fall armyworm, either through conservation of native natural enemies or augmentative release.

The fall armyworm (FAW), Spodoptera frugiperda, threatens maize production in Africa. A survey was conducted to determine the distribution of FAW and its natural enemies and damage severity in Ethiopia, Kenya and Tanzania in 2017 and 2018. A total of 287 smallholder maize farms (holding smaller than 2 hectares of land) were randomly selected and surveyed. FAW is widely distributed in the three countries and the percent of infested maize fields ranged from 33% to 100% in Ethiopia, 93% to 100% in Tanzania and 100% in Kenya in 2017, whereas they ranged from 80% to 100% and 82.2% to 100% in Ethiopia and Kenya, respectively, in 2018. The percent of FAW infestation of plants in the surveyed fields ranged from 5% to 100%. In 2017, the leaf damage score of the average of the fields ranged from 1.8 to 7 (9 = highest level of damage), while 2018, it ranged from 1.9 to 6.8. In 2017, five different species of parasitoids were recovered from FAW eggs and larvae. Cotesia icipe (Hymenoptera: Braconidae) was the main parasitoid recorded in Ethiopia, with a percent parasitism rate of 37.6%. Chelonus curvimaculatus Cameron (Hymenoptera: Braconidae) was the only egg-larval parasitoid recorded in Kenya and had a 4.8% parasitism rate. In 2018, six species of egg and larval parasitoids were recovered with C. icipe being the dominant larval parasitoid, with percentage parasitism ranging from 16% to 42% in the three surveyed countries. In Kenya, Telenomus remus (Hymenoptera: Scelionidae) was the dominant egg parasitoid, causing up to 69.3% egg parasitism as compared to only 4% by C. curvimaculatus. Although FAW has rapidly spread throughout these three countries, we were encouraged to see a reasonable level of biological control in place. Augmentative biological control can be implemented to suppress FAW in East Africa.

Occurrence of White Mango Scale (WMS), Diaspididae), in Ethiopia was known in 2010. It had remained confined to western Ethiopia where local mango trees of old age found until recently. Leaf samples infested by the pest were brought to Melkassa Agricultural Research Center (MARC) for diagnosis in June 2014. Hence, a survey to determine occurrence and distribution of the pest on mango orchards in the Central Rift Valley was conducted in August 2014. Four out of seventeen fields surveyed were infested by the pest. Of these infestation in two orchards was 100%. These orchards are located around Batu Degaga and Melkawoba about 10 Km east of MARC. Infestation in the other two orchards was very slight. Leaf infestation in the highly affected orchards ranged no single insecticide has been registered for use against the pest in Ethiopia, a new systemic insecticide spirotetramat (Movento) obtained from Bayer chemical company in Addis Ababa was tested for its efficacy to control the pest a insecticide for the control of Red scale, Aonidiella aurantii and untreated control. The study was conducted at Melkawoba located close to MARC using Randomized complete Block Design (RCBD) with three replications. Treatments were applied using motorized knapsack sprayer. Movento 150 OD and Methidathion 400 EC were applied at 1.7 and 5 ml mixed with three liters of water, respectively biweekly for a total of five times. Number of WMS per ten leaves randomly picked per treatment prior to treatment application was used to assess efficacy of the test insecticide. Number of WMS was similar after the first spray in all the treatments. After the second to fourth spray, WMS number in t was consistently higher than the insecticide treatments without significant difference between treatments. After the fifth spray population in the untreated control was significantly higher and nearly tenfold over the insecticide treatme Methidathion. Percent corrected mortality showed a progressive increase from 36 to 90% and 49 to 74 % in Movento and Methidathion treatments respectively after the second to fifth spray. The results reported in this study are preliminaries aimed at confirming presence of WMS in the CRV and to test efficacy of Movento against the pest. A study towards integrated management of the pest based on understanding the ecology of the pest need to be conducted. Insecticide screening program should focus on systemic insecticides that are less harmful to the pest's natural enemies similar to Movento considered in this study.

Background: The selection of suitable host plants for oviposition is critical for herbivorous insects to maximise survival of their offspring. Olfaction plays an important role in this process. However, little is known about how olfaction shapes the interaction between the fall armyworm (Spodoptera frugiperda) and host plants. In this study, we tested the hypothesis that olfaction guides the host selection process in the fall armyworm using oviposition and wind tunnel bioassays.Results: In no-choice and dual-choice assays, female moths oviposited on all seven host plants that were tested (maize, sorghum, wheat, bean, cowpea, tomato and cabbage). However, in multiple-choice assays, no eggs were deposited on cowpea and cabbage. We found that maize, sorghum and wheat were most preferred for oviposition, whereas cowpea was least preferred. Wind tunnel assays confirmed these divergent oviposition preferences, with maize, sorghum and wheat odours being the most attractive. Gas chromatography-mass spectrometry analysis followed by random forest classification identified terpenes as the potential host-plant attractants.Conclusion: Our results improve our understanding of the chemical ecology of the fall armyworm and suggest that some of these host plants could offer potential for use in an intercropping strategy to manage S. frugiperda.