Samira Abuelgasim Mohamed

• PhD
• Senior Researcher at International Centre of Insect Physiology and Ecology

The false codling moth, Thaumatotibia leucotreta (Meyrick) (Lepidoptera: Tortricidae) is a polyphagous insect pest that causes damage to a wide range of important fruit and vegetable crops in sub-Saharan Africa. Although it is an important pest, the effects of temperature amplitudes on the biology of T. leucotreta remain poorly understood. Temperat...

The oriental fruit fly Bactrocera dorsalis is a highly destructive and invasive pest that threatens global horticulture, causing economic losses due to fruit damage and quarantine regulations. While attract-and-kill baits are widely used to suppress fly populations, these baits also impact many non-target species. To achieve ecological sustainabili...

Multi-floral foraging sources for honey bee (Apis mellifera L.) have been threatened by landscape changes and unsustainable farming practices. In East Africa, the biodiversity of forage resources that could support honey bees, especially in agricultural lands, remains least explored. This study investigated pollen diversity for honey bees in Yatta...

BACKGROUND The cotton jassid, Amrasca biguttula, a dangerous and polyphagous pest, has recently invaded the Middle East, Africa and South America, raising concerns about the future of cotton and other food crops including okra, eggplant and potato. However, its potential distribution remains largely unknown, posing a challenge in developing effecti...

Oriental fruit fly (OFF) Bactrocera dorsalis and peach fruit fly (PFF) Bactrocera zonata are the most notorious pests that invaded Sudan in 2005 and 2012, respectively, causing severe losses and hindering horticultural production and exports. Prior to 2012, OFF was the most abundant fly in guava orchards in Gezira State. Monitoring fruit flies to d...

This study investigates the use of Ocimum tenuiflorum (Tulsi) essential oil as a natural attractant for managing Bactrocera dorsalis, a highly destructive fruit fly species worldwide. The plant was cultivated, and essential oil was extracted through hydrodistillation. Analysis of volatile compounds via Gas Chromatography-Mass Spectrometry (GC-MS) r...

Oriental fruit fly (OFF) Bactrocera dorsalis and peach fruit fly (PFF) Bactrocera zonata are the most notorious pests that invaded Sudan in 2005 and 2012, respectively, causing severe losses and hindering horticultural production and exports. Prior to 2012, OFF was the most abundant fly in guava orchards in Gezira State. Monitoring fruit flies to d...

The oriental fruit fly Bactrocera dorsalis , is a highly destructive and invasive pest that threatens global horticulture, causing economic losses through fruit damage and quarantine regulations. While attract-and-kill baits are widely used to suppress fly populations, these baits also impact many non-target species. To achieve ecological sustainab...

Guide for the management of Tomato leafminer

Koinobiont endoparasitoids regulate the physiology of their hosts through altering host immuno-metabolic responses, processes which function in tandem to shape the composition of the microbiota of these hosts. Here, we employed 16S rRNA and ITS amplicon sequencing to investigate whether parasitization by the parasitoid wasps, Diachasmimorpha longic...

Background The polyphagous alien invasive pest, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), invaded Africa and has so far spread across the continent, causing devastating impacts on maize production. In Egypt, the management of the pest by maize growers has been characterized by the application of broad-spectrum synthetic chemical...

Before the introduction of Bactrocera dorsalis (Hendel) to sub-Saharan Africa, Ceratitis cosyra (Walker) was economically the most important pest in mango farming. Its native natural enemy, the solitary parasitoid Psyttalia cosyrae (Wilkinson), played a crucial role in C. cosyra bio-control, later complemented by the exotic parasitoids Diachasmimor...

This study proposed a spatially explicit non-linear function for estimating the benefits following the release and establishment of the koinobiont endoparasitoid, Fopius arisanus at a landscape scale in Kenya to control the oriental fruit fly, Bactrocera dorsalis. The proposed model relates the bioecology of the parasitoid to its impacts on fruit g...

Fall armyworm (FAW), Spodoptera frugiperda (J.E. Smith) threatens maize, sorghum, and millet production in Africa. Despite rigorous work done to reduce FAW prevalence, the dynamics and invasion mechanisms are still poorly understood. This study applied interdisciplinary tools, analytics, and algorithms on a FAW dataset to provide insights and proje...

Abstract Fruit flies of the genus Bactrocera are the most damaging pests of horticultural crops, leading to severe economic losses affecting the national income of various countries, especially Sudan. Bactrocera dorsalis (Hendel) and Bactrocera zonata (Saunders) were reported in Sudan in 2005 and 2012, respectively. Only the male annihilation techn...

Background Koinobiont endoparasitoids regulate the physiological functioning of their hosts through altering metabolism and immune responses, processes which function in tandem to shape the structure and composition of the microbial communities of these hosts. Here we investigated the hypothesis that parasitisation by the virulent Diachasmimorpha l...

Classical biological control (CBC) has been exploited as a safer alternative for suppressing the oriental fruit fly, Bactrocera dorsalis, by importing, rearing, and releasing the larval parasitoid, Diachasmimorpha longicaudata . Although D. longicaudata has been released in Kenya through the Africa Fruit Fly Programme, the extent of its dispersal a...

BACKGROUND Maize production in Africa is hindered by a myriad of biotic challenges, key among them being invasive and native lepidopteran stemborers. Recent invasion of the continent by fall armyworm, Spodoptera frugiperda, has further exacerbated the situation. Fortunately, Cotesia icipe was found to be very promising against S. frugiperda. Howeve...

Phthorimaea absoluta (Meyrick) (= Tuta absoluta) (Lepidoptera: Gelechiidae), is the most damaging insect pest threatening the production of tomato and other solanaceous vegetables in many countries. In this study, we predicted the risk of establishment and number of generations for P. absoluta in the current and future climatic conditions under two...

The greater pumpkin fly Dacus bivittatus (Bigot) is a fruit fly indigenous to Africa, which causes extensive damage to Cucurbitaceae. To control this pest, farmers rely on synthetic chemicals, often organophosphates, which have negative effects on human health and the environment. However, the sustainable management of D. bivittatus may be obtained...

The mango mealybug Rastrococcus invadens (Williams) (Homoptera: Pseudococcidae) is a destructive and important insect pest of fruit trees in Africa and Asia, especially the mango. Females and nymphs feed on plant leaves and fruits and produce honeydew that causes sooty mold, leading to yield reduction. Although it is an important pest, the distribu...

Effective integrated pest management (IPM) of the melon fly Zeugodacus cucurbitae (Coquillett), a devastating pest threatening horticultural production in Africa, is urgently needed. In this study, a caged field experiment was implemented in Thika, Kenya to test the efficacy of Metarhizium anisopliae (Mechnikov) Sorokin ICIPE 69 for Z. cucurbitae c...

Mango is an important fruit crop in sub-Saharan Africa (SSA), including Zambia, due to its nutritional value and contribution to food security. However, the invasive and mango-infesting fruit fly is a significant constraint in mango production. Therefore, icipe and partners developed and disseminated the integrated pest management package to curb t...

Most previous studies evaluating agricultural technology adoption focus on estimating homogeneous average treatment effects across technology adopters. Understanding the heterogeneous effects and drivers of impact heterogeneity should enable interventions to be better targeted to maximise benefits. We apply machine learning using data from a random...

Sustainable production of pumpkin (Cucurbita maxima Duchesne) partly relies on integrated pest management (IPM) and pollination services. A farmer-managed field study was carried out in Yatta and Masinga Sub-Counties of Machakos County, Kenya, to determine the effectiveness of a recommended IPM package and its interaction with stingless bee colonie...

The scutum of oriental fruit fly, Bactrocera dorsalis (Hendel) (Diptera: Tephritidae), shows a high degree of variability in its colouration, which goes from black to red-brown. Such variation depicts different levels of melanin production in these individuals. In insects, melanization can have an effect on their fitness parameters, which could con...

The spread and establishment of Alien invasive species (AIS) in new environments outside their native range are increasing worldwide at an unprecedented rate due to human activities and climate change. Once they arrive in new habitats, very often the population of AIS tend to multiply at exponential rate owing to several intertwined factors, key am...

Wildflower strips are increasingly promoted in pollinator conservation schemes to maintain the stability of ecosystem services and increase crop yield. Yet, the increased area of avocado Persea americana Mill. cultivation in sub-Saharan Africa is not accompanied by measures of biodiversity conservation or the promotion of ecosystem services. We inv...

Bactrocera dorsalis (Hendel) is a major pest of fruits and vegetables worldwide with documented losses of up to 100%. Various management techniques including the use of parasitoids, such as Fopius arisanus (Sonan) and Diachasmimorpha longicaudata (Ashmead) (Hymenoptera: Braconidae) within the context of the Integrated Pest Management (IPM) approach...

Simple Summary Tephritid fruit flies are a major threat to fruit production in sub-Saharan Africa. Central Africa has lagged considerably behind the rest of the world in fruit fly knowledge and management. In six consecutive years of research, we developed new knowledge on the diversity, seasonality, attraction to various lures/baits, and fruit inf...

The False codling moth (FCM), Thaumatotibia leucotreta is a major quarantine pest that hampers Capsicum production and trade in sub-Saharan Africa (SSA) and may need a postharvest treatment to meet quarantine standards of lucrative overseas markets. In this study, we evaluated the efficacy of hot water treatment (HWT) as a potential nonchemical qua...

Simple Summary The melon fly Zeugodacus cucurbitae is an invasive fruit fly that causes extensive damage to many fruit crops. Sustainable management of this pest can be achieved through environmentally friendly and safely integrated pest management (IPM), in which the use of biopesticides is a key component. In this study, various isolates of entom...

Following the invasion of Africa by the oriental fruit fly, Bactrocera dorsalis, Classical biological control (CBC) has been exploited as a safer alternative for its suppression by the introduction and release of the koinobiont endoparasitoid, Fopius arisanus. Although the parasitoids have been released in several African countries, the extent of t...

Simple Summary Tuta absoluta is an invasive pest threatening the productivity of the tomato crop. Dolichogenidea gelechiidivoris was imported and released as a natural enemy of Tuta absoluta. Mapping the efficacy of Dolichogenidea gelechiidivoris can improve its use as a control agent against Tuta absoluta. The Dolichogenidea gelechiidivoris effica...

Using synthetic pesticides to manage pests can threaten pollination services, affecting the productivity of pollination-dependent crops such as avocado. The need to mitigate this negative externality has led to the emergence of the concept of integrated pest and pollinator management (IPPM) to achieve both pest and pollinator management, leading to...

Background The western flower thrips, Frankliniella occidentalis, is a quarantine pest of French beans that requires phytosanitary treatment to meet quarantine requirements for strict lucrative markets. In this study, the efficacy of hot water treatment against F. occidentalis eggs and its effects on the postharvest physicochemical quality paramete...

Classical biological control (CBC) is considered a safer and more sustainable alternative for management of alien invasive species (AIS). This review presents recent advances in CBC of key horticultural insect pests using parasitoids in Africa. Several CBC programs have been undertaken targeting different insect pests of both fruits and vegetables,...

BACKGROUND The white mango scale, Aulacaspis tubercularis (Hemiptera: Diaspididae), is an invasive pest that threatens the production of several crops of commercial value including mango. Though it is an important pest, little is known about its biology and ecology. Specifically, information on habitat suitability of A. tubercularis occurrence and...

Tomato cultivation is threatened by the infestation of the nocturnal invasive tomato pinworm, Tuta absoluta. This study was based on field observations that a wild tomato plant, Solanum lycopersicum var. cerasiforme, grown in the Mount Kenya region, Kenya, is less attacked by T. absoluta, unlike the cultivated tomato plants like S. lycopersicum (va...

Generating tree-specific crop maps within heterogeneous landscapes requires imagery of fine spatial and temporal resolutions to discriminate among the rapid transitions in tree phenological and spectral features. The availability of freely accessible satellite data of relatively high spatial and temporal resolutions offers an unprecedented opportun...

Dolichogenidea gelechiidivoris (Marsh) (Syn. Apanteles gelechiidivoris) (Hymenoptera: Braconidae), a konoibiont larval endoparasitoid of the South American tomato pinworm Tuta absoluta (Meyrick), was imported into Kenya in 2017 for the first classical biological control of T. absoluta in Africa. We determined the thermal thresholds of D. gelechiidi...

There are various postharvest treatments currently available in the market. Among these, heat-based treatments are very effective. Several hot water treatment (HWT) protocols at various temperature regimes and time durations have been developed for different mango cultivars and varieties. However, many concerns have been raised regarding the qualit...

Kairomones are semiochemicals that are emitted by an organism and which mediate interspecific interaction that is of benefit to an organism of another species that receives these chemical substances. Parasitoids find and recognize their hosts through eavesdropping on the kairomones emitted from the by-products or the body of the host. Hemipteran in...

Following the invasion of Africa by the oriental fruit fly, Bactrocera dorsalis, Classical biological control (CBC) have been exploited as a safer alternative for its suppression by the introduction and release of the koinobiont endoparasitoid, Fopius arisanus. Although, the parasitoids have been released in several African countries, its extent of...

Semiochemicals such as herbivore-induced plant volatiles (HIPVs) and host chemicals serve as communication signals for parasitoids searching for oviposition sites. The braconid koinobiont endoparasitoid Dolichogenidea gelechiidivoris (Hymenoptera: Braconidae) efficiently parasitises larvae of Tuta absoluta (Lepidoptera: Gelechiidae), a major pest o...

Fruit production in Sub-Saharan Africa is of paramount importance both socially and economically. Millions of farmers derive livelihoods from mango, avocado, citrus, cashew, and coconut farming, but native and alien invasive species constrain production The region’s capacity to contain invasives is weak due to the absence of national and institutio...

After five years of its first report on the African continent, Fall armyworm (FAW), Spodoptera frugiperda (J.E. Smith) is considered a major threat to maize, sorghum, and millet production in sub-Saharan Africa. Despite the rigorous work already conducted to reduce FAW prevalence, the dynamics and invasion mechanisms of FAW in Africa are still poor...

In sub-Saharan Africa (SSA), tomato is an economically important crop that contributes not only to employment and income, but also food security. Like the rest of the SSA countries, tomato production in Kenya is constrained mainly by pests and diseases, key among them being the tomato leaf miner (Tuta absoluta), which can cause 80–100% losses if no...

Simple Summary Tuta absoluta is an invasive insect pest that has spread widely and established itself in many countries since its first detection in Spain in 2006. The devastating moth originates in South America and attacks tomato and other solanaceous vegetables, leading to huge losses in yield and potential income particularly for small-scale fa...

The South American tomato pinworm, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), has invaded most Afro-Eurasian countries and is threatening worldwide tomato production. Various strategies have been developed and implemented to manage this pest. Here, we present a timely review on the up-to-date development and practical implementation of int...

Agricultural growth and food security are a priority in many developing countries. This has led to increased attention to effective pest management. Integrated Pest Management (IPM) strategy is a sustainable and recommended alternative to the use of synthetic pesticides in the management of tomato pests, with Tuta absoluta being the major one. This...

Simple Summary The oriental fruit fly Bactrocera dorsalis is a major quarantine pest in sub-Saharan Africa that threatens mango production and international trade. In this study, we developed a hot water treatment (HWT) protocol for the post-harvest disinfestation of B. dorsalis and assessed its impact on cv. Tommy Atkins mango quality parameters a...

This study assessed the nontarget effect of entomopathogenic fungi on the Western honey bee Apis mellifera L. and the African stingless bee Meliponula ferruginea Cockrell (Hymenoptera: Apidae). Pathogenicity of five Metarhizium anisopliae (ICIPE 7, ICIPE 20, ICIPE 62, ICIPE 69, and ICIPE 78) (Metschnikoff) Sorokin (Hypocreales: Clavicipitaceae) and...

Simple Summary Combining natural enemies may lead to synergistic, additive, or antagonistic effects on the control of insect pests. An investigation into the nature and outcome of the interaction between a generalist mirid predator, Nesidiocoris tenuis, and a specialist koinobiont larval endoparasitoid, Dolichogenidea gelechiidivoris, in the contro...

The African citrus triozid (ACT), Trioza erytreae Del Guercio (Hemiptera: Triozidae), is the major vector of the ‘Candidatus Liberibacter africanus’, associated with the African citrus greening disease [huanglongbing (HLB)]. Although T. erytreae is a very destructive pest in citrus production with yield losses up to 100%, there is limited informati...

Hot Water Treatment (HWT) provides adequate phytosanitary assurance that treated fruits and vegetables exported abroad are free from devastating quarantine pests. Two systems for HWT are currently available for commercial use namely the batch/jacuzzi and the continuous flow system depending on user requirements. Several protocols have been develope...

The braconid parasitoid Diachasmimorpha longicaudata (Ashmead) (Hymenoptera: Braconidae) is one of the most important natural enemies in classical biological control programs against tephritid fruit flies worldwide. In light of the spread of the invasive fruit fly species, Bactrocera dorsalis in Africa and beyond, there is a need to implement class...

BACKGROUND Biological control plays a key role in reducing crop damage by Tuta absoluta (Meyrick) and Trialeurodes vaporariorum (Westwood), which cause huge yield losses in tomato (Solanum lycopersicum L.). The mirid predator Nesidiocoris tenuis (Reuter) preys heavily on these pests, with satisfying control levels in tomato greenhouses. Although N....

African traditional crops (Poaceae), including sorghum (Sorghum bicolour (L.) Moench), pearl millet (Pennisetum glaucum (L.) R. Br.), finger millet (Eleusine coracana (L.) Gaertn) and African rice (Oryza glaberrima Steud), are the most widely cultivated cereal crops in Africa. However, maize (Zea mays L.) cultivation has exceeded the production of...

Insect pollinators provide an important ecosystem service by improving agricultural productivity. However, their populations have been declining in recent years due to excessive use of synthetic pesticides, climate and land use/land cover (LULC) changes. Climate and LULC changes have resulted in land fragmentation and consequently pollinator habita...

Tuta absoluta (Meyrick) has become a serious menace to sustainable production of tomato in Kenya. A survey was conducted between April 2015 and June 2016 to determine its distribution, abundance, infestation, and damage levels on tomato, and associated natural enemies. Trap counts of T. absoluta moths were recorded in all surveyed 29 counties, whic...

Kairomones are chemical signals that mediate interspecific interactions beneficial to organisms that detect the cues. These attractants can be individual compounds or mixtures of herbivore-induced plant volatiles (HIPVs) or herbivore chemicals such as pheromones, i.e., chemicals mediating intraspecific communication between herbivores. Natural enem...

Simple Summary The fall armyworm (FAW), Spodoptera frugiperda has now become a pest of global importance. Its introduction and detection in Africa in 2016, and subsequent introduction and spread into Asia and Australia, has put several millions of food producers and maize farmers at risk. Not all pest management strategies are sustainable. Biologic...

The African citrus triozid (ACT), Trioza erytreae, is an important pest of citrus. Both nymphs and adults damage the plant by feeding on the sap causing young shoots to die. Trioza erytreae also vectors Candidatus Liberibacter africanus, the bacteria that cause citrus greening disease. Since certain non‐host plants are known to repel insect pests,...

Whiteflies (Hemiptera: Aleyrodidae) are devastating agricultural pests of economic importance vectoring pathogenic plant viruses. Knowledge on their diversity and distribution in Kenya is scanty, limiting development of effective sustainable management strategies. The present study is aimed at identifying whitefly pest species present in Kenya acro...

A sound IPM management for false codling moth (FCM), Thaumatotibia leucotreta, a devastating pest threatening horticultural production in Africa, is urgently needed. The compatibility of the dry conidia of virulent fungal isolate, Metarhizium anisopliae ICIPE 69 with FCM sex pheromone (Crytrack®) in the autoinoculation was assessed. The effect of t...

Rastrococcus iceryoides (Green) (Homoptera: Pseudococcidae) is a major invasive pest of several horticultural crops [in Africa and Asia, outside its native range in India], with damage levels ranging from 30% to complete crop failure. Due to lack of effective co-evolved parasitoids in the invaded regions, maximum entropy (MaxEnt) and genetic algori...

Natural enemies locate their herbivorous host and prey through kairomones emitted by host plants and herbivores. These kairomones could be exploited to attract and retain natural enemies in crop fields for insect pest control. The parasitoid Encarsia formosa preferentially parasitises its whitefly host, Trialeurodes vaporariorum, a major pest of to...

The spotted wing drosophila, Drosophila suzukii Matsumura, is an insect pest of soft-skinned fruit, native to Eastern Asia. Since 2008, a world-wide dispersal of D. suzukii is seen, characterized by the establishment of the pest in many Asian, American and European countries. While the potential for invasion of continental Africa by D. suzukii has...

The peach fruit fly Bactrocera zonata (Saunders) (Diptera: Tephritidae) is an important invasive species causing substantial losses to the horticulture industry worldwide. Despite the severe economic impact caused by this pest in its native and invaded range, information on its potential range expansion under changing climate remains largely unknow...

There was a typo in the fifth author's name in the initial online publication. The original article has been corrected.

Background Symbiotic interactions between insects and bacteria have been associated with a vast variety of physiological, ecological and evolutionary consequences for the host. A wide range of bacterial communities have been found in association with the oriental fruit fly, Bactrocera dorsalis (Hendel) (Diptera: Tephritidae), an important pest of c...

Simple Summary Wasps, generally referred to as “farmers friends” because of their ability to control devastating fruit flies, were imported from Hawaii and released in Kenya for the management of the invasive Oriental fruit fly Bactrocera dorsalis. It was noted that the introduced wasp had developed a liking for the native fruit fly species Ceratit...

Simple Summary: Wasps, generally referred to as "farmers friends" because of their ability to control devastating fruit flies, were imported from Hawaii and released in Kenya for the management of the invasive Oriental fruit fly Bactrocera dorsalis. It was noted that the introduced wasp had developed a liking for the native fruit fly species Cerati...

Tuta absoluta Meyrick originates in South America and is now one of the most important insect pests of Solanaceae in different parts of the world, including Africa. Its control has relied primarily on chemical insecticides, which are associated with negative ecological effects. In the present study, essential oils of Ocimum gratissimum and O. kilim...

Methanolic extracts of liana of Caesalpinia welwitschiana and leaves of C. bonduc were found to possess moderate antifeedant and ovicidal activities against Tuta absoluta. Bioassay-guided isolation of constituents from the most active fraction of C. welwitschiana led to the identification of four known compounds [isobonducellin 1a and bonducellin 1...