Entomology Commons^™

Crop Pests And Predators Exhibit Inconsistent Responses To Surrounding Landscape Composition, Daniel S. Karp, Julie A. Peterson, 155 Other Co-Authors

Faculty Publications: Department of Entomology

The idea that noncrop habitat enhances pest control and represents a win–win opportunity to conserve biodiversity and bolster yields has emerged as an agroecological paradigm. However, while noncrop habitat in landscapes surrounding farms sometimes benefits pest predators, natural enemy responses remain heterogeneous across studies and effects on pests are inconclusive. The observed heterogeneity in species responses to noncrop habitat may be biological in origin or could result from variation in how habitat and biocontrol are measured. Here, we use a pest-control database encompassing 132 studies and 6,759 sites worldwide to model natural enemy and pest abundances, predation rates, and crop …

Varroa-Specific Hygienic Behavior Of Apis Mellifera Scutellata In Kenya, Sammy Kiprotich Cheruiyot, H. Michael G. Lattorff, Ruth Kahuthia-Gathu, Jenard Patrick Mbugi, Elliud Muli

All Peer-Reviewed Publications

Varroa-specific hygienic behavior is a hereditary trait of honey bee (Apis mellifera), which supports resistance to Varroa destructor. This study investigated the response of Apis mellifera scutellata to Varroa-infested worker brood cells in Kenya, East Africa. Uncapping, removal of the brood, and disappearance of the introduced mite were recorded in a total of 690 cells into which live mites were introduced. We recorded a high proportion of untouched cells in controls (median, 80%) compared to manipulated cells in which mites had been introduced (median, 12.5%) with a significant difference (GLMM, p < 0.001). Mites were removed and cells were recapped in about 26% of the artificially infested brood cells. When ten, eight, and five mites were singly introduced in closely neighboring brood cells, hygienic bees were more responsive in the high mite density regime of eight and ten mites, an indication of a possibility that chemicals play a role in identification of Varroa-infested brood cells.

The Effect Of Imidacloprid On Honey Bee Queen Fecundity, Jamilyn Martin, Julia D. Fine, Amy Cash-Ahmed, Gene E. Robinson

PRECS 2018

Imidacloprid is a neonicotinoid insecticide commonly used in agricultural settings to control insect pests by acting as an agonist of acetylcholine receptors and inducing paralysis and mortality. In small doses, imidacloprid can cause loss of memory and foraging ability along with impaired learning and a lowered immune response in western honey bees (Apis mellifera). Effects of neonicotinoid insecticides on colony reproduction have been documented including decreased colony expansion, queen failure and replacement, and decreased queen egg laying.

For this study, we examined the effects of imidacloprid on the fecundity of queen bees when their worker attendants were exposed to low …

Spatial Distribution Of Bactrocera Dorsalis And Thaumatotibia Leucotreta In Smallholder Avocado Orchards Along Altitudinal Gradient Of Taita Hills And Mount Kilimanjaro, James J. Odanga, Samira Mohamed, Sizah Mwalusepo, Florence Olubayo, Richard Nyankanga, Fathiya Khamis, Ivan Rwomushana, Tino Johansson, Sunday Ekesi

All Peer-Reviewed Publications

Avocado (Persea americana) fruits are an important source of income and a nutritious food for small-scale growers and other stakeholders involved in farming along the Afrotropical highlands of Taita Hills and Mount Kilimanjaro in Kenya and Tanzania, respectively. Avocado fruits are infested by several insect pests, namely the Asian invasive fruit fly, Bactrocera dorsalis (Hendel) (Diptera: Tephritidae), and the false codling moth, Thaumatotibia leucotreta Meyrick (Lepidoptera: Tortricidae). However, there is inadequate information on the distribution patterns of these pests in small-scale avocado cropping systems in the East African highlands. This study was initiated to generate a spatial distribution map of …

Prediction Of Insect Pest Distribution As Influenced By Elevation: Combining Field Observations And Temperature-Dependent Development Models For The Coffee Stink Bug, Antestiopsis Thunbergii (Gmelin), Abdelmutalab G.A. Azrag, Christian W.W. Pirk, Abdullahi A. Yusuf, Fabrice Pinard, Saliou Niassy, Gladys Mosomtai, Régis Babin

All Peer-Reviewed Publications

The antestia bug, Antestiopsis thunbergii (Gmelin 1790) is a major pest of Arabica coffee in Africa. The bug prefers coffee at the highest elevations, contrary to other major pests. The objectives of this study were to describe the relationship between A. thunbergii populations and elevation, to elucidate this relationship using our knowledge of the pest thermal biology and to predict the pest distribution under climate warming. Antestiopsis thunbergii population density was assessed in 24 coffee farms located along a transect delimited across an elevation gradient in the range 1000–1700 m asl, on Mt. Kilimanjaro, Tanzania. Density was assessed for three …

Radical Social Ecology As Deep Pragmatism: A Call To The Abolition Of Systemic Dissonance And The Minimization Of Entropic Chaos, Arielle Brender

Student Theses 2015-Present

This paper aims to shed light on the dissonance caused by the superimposition of Dominant Human Systems on Natural Systems. I highlight the synthetic nature of Dominant Human Systems as egoic and linguistic phenomenon manufactured by a mere portion of the human population, which renders them inherently oppressive unto peoples and landscapes whose wisdom were barred from the design process. In pursuing a radical pragmatic approach to mending the simultaneous oppression and destruction of the human being and the earth, I highlight the necessity of minimizing entropic chaos caused by excess energy expenditure, an essential feature of systems that aim …

Fate Of Methoprene In Temperate Salt Marsh Ditches Following Aerial Applications, David J. Tonjes, Anne E. Mcelroy, Robin K. Barnes, Dominick V. Ninivaggi, Walter Dawydiak, Gregory T. Greene, Bruce J. Brownawell

Technology & Society Faculty Publications

Aerial applications of liquid methoprene are used in salt marshes to control mosquitoes by preventing adult emergence. Despite concern about toxicity to non-target organisms, little is known about environmental concentrations after applications, nor methoprene's persistence in salt marsh environments. Aqueous and sediment samples were collected from two marshes receiving weekly applications. Aqueous samples were collected as early as 30 minutes after applications and as long as nine days afterwards; sediment samples were taken within hours of application and as long as 19 days post-application. Use of time-of-flight liquid chromatography – mass spectral analysis allowed for ultra low detection limits (0.5 …

Can Increasing Grass-Fungal Endophyte Symbiotic Diversity Enhance Grassland Ecosystem Functioning?, Mahtaab Bagherzadeh

Theses and Dissertations--Plant and Soil Sciences

The relationship between biodiversity and ecosystem functioning is important in maintaining agroecosystem sustainability. Plant-microbe symbioses, such as exists between the grass tall fescue (Schedonorus arundinaceum) and the asexual fungal endophyte Epichloë coenophiala, can be utilized to enhance agroecosystem functions, such as herbivore resistance. “Novel” E. coenophiala strains that vary in the production of mammal- and insect-toxic compounds have been identified, inserted into tall fescue cultivars, and are planted in pastures globally. Novel fungal endophyte-tall fescue associations may have divergent ecosystem function effects. This study assessed effects of different fescue-endophyte symbiotic combinations on pasture ecosystem function, including aboveground …

Temperature-Dependent Models Of Development And Survival Of An Insect Pest Of African Tropical Highlands, The Coffee Antestia Bug Antestiopsis Thunbergii (Hemiptera: Pentatomidae), Abdelmutalab G.A. Azrag, Lucy K. Murungi, Henri E.Z. Tonnang, Dickson Mwenda, Régis Babin

All Peer-Reviewed Publications

The antestia bug Antestiopsis thunbergii (Hemiptera: Pentatomidae) is a major pest of Arabica coffee in African tropical highlands. It feeds on coffee plant vegetative parts and berries leading to a direct reduction in coffee yield and quality. This study aimed to determine A. thunbergii thermal requirements, and to obtain new information on the pest demography as influenced by temperature. Temperature-dependent models were developed using the Insect Life Cycle Modelling software (ILCYM) through a complete life table study at seven constant temperatures in the range 18–32 °C. Non-linear functions were fitted to A. thunbergii development, mortality, fecundity and senescence. Model parameters …

Vegetation And Arthropod Responses To Brush Reduction By Grubbing And Stacking, Carter Crouch, J. Alfonso Ortega-Santos, David B. Wester, Fidel Hernández, Leonard A. Brennan, Greta L. Schuster

National Quail Symposium Proceedings

Grubbing is a mechanical brush-reduction technique that allows targeting of mesquite (Prosopis glandulosa) and huisache (Vachellia farnesiana) and can be used to open lanes for hunting northern bobwhites (Colinus virginianus). Follow-up treatments of stacking allow the piling up of downed brush. We initiated this study on the Santa Gertrudis Division of the King Ranch, Inc., Texas, to determine effects of grubbing and stacking on vegetation and arthropod communities important to bobwhite. We hypothesized that grubbing and stacking would be able to selectively remove mesquite and huisache while leaving mixed brush species largely intact. We …

Potential Distribution Dataset Of Honeybees In Indian Ocean Islands: Case Study Of Zanzibar Island, Sizah Mwalusepo, Eliud Muli, Kiatoko Nkoba, Everlyn Nguku, Joseph Kilonzo, Elfatih M. Abdel-Rahman, Tobias Landmann, Asha Fakih, Suresh Raina

All Peer-Reviewed Publications

Honeybees (Apis mellifera) are principal insect pollinators, whose worldwide distribution and abundance is known to largely depend on climatic conditions. However, the presence records dataset on potential distribution of honeybees in Indian Ocean Islands remain less documented. Presence records in shape format and probability of occurrence of honeybees with different temperature change scenarios is provided in this article across Zanzibar Island. Maximum entropy (Maxent) package was used to analyse the potential distribution of honeybees. The dataset provides information on the current and future distribution of the honey bees in Zanzibar Island. The dataset is of great importance for improving stakeholders …

Effects Of A Prescribed Burn On The Adult Butterfly Assemblage Of A Coastal Grassland, J. Nicole Desha, Joseph Colbert, Kimberly M. Andrews, Scott Coleman, C. Tate Holbrook

Georgia Journal of Science

Coastal grasslands are globally threatened by development and natural succession. In the southeastern United States, these increasingly rare ecosystems are being managed using prescribed fire, but ecological responses to fire management are largely unknown, particularly among nontargeted species. We tested for short-term effects of controlled burning on the abundance and species richness of adult butterflies, which utilize coastal grasslands for nectaring resources and as migratory stopover sites. In February 2015, four plots of coastal grassland on Little St. Simons Island, GA were burned and paired with unburned (control) plots of equal size. Throughout the following summer-fall flight season, we conducted …

Impact Of Habitat Degradation On Species Diversity And Nest Abundance Of Five African Stingless Bee Species In A Tropical Rainforest Of Kenya, Nkoba Kiatoko, Suresh Kumar Raina, Frank Van Langevelde

All Peer-Reviewed Publications

Natural habitat degradation often involves the reduction or disappearance of bee species. In Africa, stingless bees are hunted for honey, which is used as food, for medicinal purposes, and for traditional rituals. Severe habitat degradation due to human settlement is hypothesized to have a negative impact on the species diversity of the African stingless bee species. In this paper, we assess the impact of habitat degradation on the diversity of five stingless bee species across different habitats in the tropical rainforest of Kenya (indigenous forest, mixed indigenous forest) and its neighbouring landscape (grassland, village) in western Kenya. The species fauna, …

You Are What You Eat: Food-Drug Interaction In Honey Bees (Apis Mellifera), Allison G. Kelley, Liao Ling-Hsiu, May Berenbaum

PRECS student projects

The research featured in this poster examined how phytochemicals in nectar and pollen (quercetin and p-coumaric acid), which are known to upregulate cytochrome P450 detoxification enzymes, affect honey bee survival in combination with the pesticides propiconazole, a fungicide, and chlorantraniliprole, an insecticide. While consuming either phytochemical in the absence of pesticides can prolong longevity, consumption of pesticides reduced bee lifespan significantly with or without phytochemicals present.

Honey Bee Gut Dysbiosis: A Novel Context Of Disease Ecology, Kirk E. Anderson, Vincent A. Ricigliano

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

The honey bee microbiota has become a hot-spot of recent research. Highly co-evolved with its host, the hindgut microbiota of a worker honey bee consists of six bacterial species shown to occur reliably in particular proportions. Altered microbiota structure is associated with host deficiencies, and a variety of bacteria found throughout the hive environment can dominate the worker gut suppressing or displacing microbiota function. The synthesis presented here suggests environmental insults alter gut bacterial balance, leading to decreased host function and disease progression. Specific functional groups of native bacteria represent a model system to investigate dysbiosis and the evolution of …

Advances In Crop Insect Modelling Methods—Towards A Whole System Approach, Henri E.Z. Tonnang, Bisseleua D.B. Hervé, Lisa Biber-Freudenberger, Daisy Salifu, Sevgan Subramanian, Valentine B. Ngowi, Ritter Y.A. Guimapi, Bruce Anani, Francois M.M. Kakmeni, Hippolyte Affognon, Saliou Niassy, Tobias Landmann, Frank T. Ndjomatchoua, Sansao A. Pedro, Tino Johansson, Chrysantus M. Tanga, Paulin Nana, Komi M. Fiaboe, Samira F. Mohamed, Nguya K. Maniania, Sunday Ekesi, Christian Borgemeister

All Peer-Reviewed Publications

A wide range of insects affect crop production and cause considerable yield losses. Difficulties reside on the development and adaptation of adequate strategies to predict insect pests for their timely management to ensure enhanced agricultural production. Several conceptual modelling frameworks have been proposed, and the choice of an approach depends largely on the objective of the model and the availability of data. This paper presents a summary of decades of advances in insect population dynamics, phenology models, distribution and risk mapping. Existing challenges on the modelling of insects are listed; followed by innovations in the field. New approaches include artificial …

Elucidating The Effects Of Thiamethoxam Neonicotinoid On Honey Bee Learning Using The Proboscis Extension Response, David J. Shepherd

Undergraduate Honors Theses

In this study, the effects of the neonicotinoid pesticide, thiamethoxam, are examined through the Proboscis Extension Response (PER) in honey bees (Apis mellifera). PER is a form of classical conditioning applied to honey bees through scent and reward association which quantifies learning rates. Results between groups treated with thiamethoxam did not differ significantly from untreated control groups. Potential reasons for these results are discussed. The method and experimental apparatus for testing the PER assay are also discussed.

Unity In Defence: Honeybee Workers Exhibit Conserved Molecular Responses To Diverse Pathogens, Vincent Doublet, Yvonne Poeschl, Andreas Gogol-Döring, Cédric Alaux, Desiderato Annoscia, Christian Aurori, Seth M. Barribeau, Oscar C. Bedoya-Reina, Mark J.F. Brown, James C. Bull, Michelle L. Flenniken, David A. Galbraith, Elke Genersch, Sebastian Gisder, Ivo Grosse, Holly L. Holt, Dan Hultmark, H. Michael G. Lattorff, Yves Le Conte, Fabio Manfredini, Dino P. Mcmahon, Robin F.A. Moritz, Francesco Nazzi, Elina L. Niño, Katja Nowick, Ronald P. Van Rij, Robert J. Paxton, Christina M. Grozinger

All Peer-Reviewed Publications

Background: Organisms typically face infection by diverse pathogens, and hosts are thought to have developed specific responses to each type of pathogen they encounter. The advent of transcriptomics now makes it possible to test this hypothesis and compare host gene expression responses to multiple pathogens at a genome-wide scale. Here, we performed a meta-analysis of multiple published and new transcriptomes using a newly developed bioinformatics approach that filters genes based on their expression profile across datasets. Thereby, we identified common and unique molecular responses of a model host species, the honey bee (Apis mellifera), to its major pathogens and parasites: …

Temperature-Dependent Phenology Of Plutella Xylostella (Lepidoptera: Plutellidae): Simulation And Visualization Of Current And Future Distributions Along The Eastern Afromontane, Benignus V. Ngowi, Henri E.Z. Tonnang, Evans M. Mwangi, Tino Johansson, Janet Ambale, Paul N. Ndegwa, Sevgan Subramanian

All Peer-Reviewed Publications

There is a scarcity of laboratory and field-based results showing the movement of the diamondback moth (DBM) Plutella xylostella (L.) across a spatial scale. We studied the population growth of the diamondback moth (DBM) Plutella xylostella (L.) under six constant temperatures, to understand and predict population changes along altitudinal gradients and under climate change scenarios. Non-linear functions were fitted to continuously model DBM development, mortality, longevity and oviposition. We compiled the best-fitted functions for each life stage to yield a phenology model, which we stochastically simulated to estimate the life table parameters. Three temperature-dependent indices (establishment, generation and activity) were …

A Comparison Of Benthic Macroinvertebrate Assemblages Between Perennial And Intermittent Headwater Streams Of The Mattole River In Northern California, Usa, Mason S. London

Cal Poly Humboldt theses and projects

Intermittent streams are common throughout the world and comprise 60% or more of total river lengths in the conterminous United States. Despite their prevalence, intermittent streams are understudied, particularly first-order headwater streams, which are vital for maintaining the function, health and biotic diversity of river networks. In June 2016, I sampled five intermittent and five perennial headwater streams in the Mattole River watershed in northwestern coastal California, USA, to compare benthic macroinvertebrate (BMI) assemblages between intermittent and perennial streams. BMI samples were collected using a 500µm mesh D-net at eight randomly located riffles along a 150-m reach, and then composited, …

Blow Fly (Diptera: Calliphoridae) Responses To Different Colors Of Baited Traps, Oluwadamilola Olufunso Oke

Honors College Theses

Blow flies (Diptera: Calliphoridae) are usually the first insects to colonize human remains. By determining the time of colonization, a postmortem interval (PMI), or “time of death”, can be estimated. To develop more accurate PMI estimates, it is important for forensic entomologists to understand the cues that Blow flies use to locate vertebrate remains. The purpose of this study was to determine whether Blow flies use visual cues, in addition to olfactory cues, to locate carrion. Two colors of fly traps, clear and green, were constructed and chicken gizzard used as bait. Three Blow fly species exhibited a significant preference …

The Plant As A Habitat For Entomophagous Insects, L. Kaiser, P. Ode, S. Van Nouhuys, P. A. Calatayud, S. Colazza, A. M. Cortesero, A. Thiel, J. Van Baaren

All Peer-Reviewed Publications

Populations of herbivorous insects are naturally consumed by other predacious or predatory insect species. These entomophagous insects are thus plant-dwelling organisms that use the plant for several vital functions and are affected by plant traits at the evolutionary, organism and population levels. Many entomophagous species are used for the biological control of insect pests worldwide. The aim of this chapter is to provide an exhaustive review of mechanisms underlying the interactions between plants and entomophagous insects, including those governing life history traits at the individual level, as well as those acting on population and community structure and dynamics. We detail …

Entomopathogens Routinely Used In Pest Control Strategies: Orchards In Tropical Climate, N. K. Maniania, S. Ekesi, C. Dolinski

All Peer-Reviewed Publications

Fruit and nut trees such as mango, pineapples, papaya, banana, guava, cashew, passion fruit, and avocado are important components of tropical ecosystems. They are sources of vitamins, minerals and carbohydrates and have great economic importance as sources of both household incomes and national revenues. Fruit and nut trees provide important adaptive values and tend to be more resilient to climate change due to their perennial nature, and they have the property of sequestering carbon. World production and trade of fresh tropical fruit are expected to expand over decades, with developing countries accounting for about 98% of total production, while developed …

Plant–Insect Interactions In A Changing World, S. Pincebourde, J. Van Baaren, S. Rasmann, P. Rasmont, G. Rodet, B. Martinet, P. A. Calatayud

All Peer-Reviewed Publications

Global change is resetting the spatial and ecological equilibrium of complex co-evolutionary relationships between plants and their insect herbivores. We review the mechanisms at play in the responses of plant–insect interactions to global changes, including increased temperature and atmospheric CO2 concentrations, modification of land use and pollution. We distinguish between the direct effects of global changes on each partner from the indirect impacts on insects via the responses of plants. The indirect effects include a change in the nutritional quality of the plant tissues for herbivore insects, as well as a change in the microclimatic conditions at the leaf surface. …

Predicting Post-Fire Change In West Virginia, Usa From Remotely-Sensed Data, Michael Strager P. Strager, Melissa Thomas-Van Gundy, Aaron E. Maxwell

Journal of Geospatial Applications in Natural Resources

Prescribed burning is used in West Virginia, USA to return the important disturbance process of fire to oak and oak-pine forests. Species composition and structure are often the main goals for re-establishing fire with less emphasis on fuel reduction or reducing catastrophic wildfire. In planning prescribed fires land managers could benefit from the ability to predict mortality to overstory trees. In this study, wildfires and prescribed fires in West Virginia were examined to determine if specific landscape and terrain characteristics were associated with patches of high/moderate post-fire change. Using the ensemble machine learning approach of Random Forest, we determined that …

Molecular Comparison Of Cattle Fever Ticks From Native And Introduced Ranges, With Insights Into Optimal Search Areas For Classical Biological Control Agents, John A. Goolsby, F. D. Guerrero, John F. Gaskin, K. G. Bendele, P. Azhahianambi, D. Amalin, M. Flores-Cruz, J. Kashefi, Alexis Racelis

School of Earth, Environmental, & Marine Sciences Faculty Publications

Cattle fever ticks, the southern cattle tick, Rhipicephalus microplus (Canestrini), and cattle tick, Rhipicephalus annulatus (Say), are livestock pests endemic to Mexico and invasive along the Texas-Mexico border. Resistance to acaricide, alternate wildlife hosts, and pathogenic landscape-forming weeds present challenges for sustainable eradication of this pest in the U.S. Classical biological control is being explored as a strategy to control cattle fever ticks, especially on alternate hosts such as nilgai antelope, Boselaphus tragocamelus (Pallas), and white-tailed deer, Odocoileus virginianus (Zimmermann). Molecular genetic tools were used to compare populations of cattle fever ticks from native and introduced ranges to provide insights …

Chemical Parameters And Bacterial Communities Associated With Larval Habitats Of Anopheles, Culex And Aedes Mosquitoes (Diptera: Culicidae) In Western Kenya, Thomas Ogao Onchuru, Yvonne Ukamaka Ajamma, Marion Burugu, Martin Kaltenpoth, Daniel Masiga, Jandouwe Villinger

All Peer-Reviewed Publications

Aquatic larval habitat conditions influence the development, fitness and vectorial capacity of mosquitoes. In turn, human activities can influence these conditions and shape mosquito vector distribution, thus affecting pathogen circulation and transmission. We measured environmental factors (chemical and microbial) in mosquito larval habitats and evaluated their potential as predictors for the occurrence of different mosquito species in an arbovirus and malaria endemic region of western Kenya.We found significantly greater proportions of Aedes aegypti mosquito larvae in ammonium and phosphate rich habitats, suggesting that fertilizer usage could potentially increase aquatic habitat suitability and Aedes vectored disease transmission. Anopheles gambiae larval habitats …

Prospects For Repellent In Pest Control: Current Developments And Future Challenges, Emilie Deletre, Bertrand Schatz, Denis Bourguet, Fabrice Chandre, Livy Williams, Alain Ratnadass, Thibaud Martin

All Peer-Reviewed Publications

The overall interest in environmentally safe pest control methods and the rise of insecticide resistance in pest populations have prompted medical and agricultural entomology research on insect repellents in recent years. However, conducting research on repellent is challenging for several reasons: (1) the different repellent phenomena are not well defined; (2) it is difficult to test for and quantify repellent; (3) the physiological mechanisms are poorly known; (4) the field efficacy appears to be highly variable. Here, we identified five different types of repellent: expellency, irritancy, deterrency, odor masking and visual masking, and described behavioral bioassays to differentiate between them. …

Vector Competence Of Aedes Aegypti In Transmitting Chikungunya Virus: Effects And Implications Of Extrinsic Incubation Temperature On Dissemination And Infection Rates, Sophiah Mbaika, Joel Lutomiah, Edith Chepkorir, Francis Mulwa, Christopher Khayeka-Wandabwa, Caroline Tigoi, Elijah Oyoo-Okoth, James Mutisya, Zipporah Ng'ang'a, Rosemary Sang

All Peer-Reviewed Publications

Background: Aedes aegypti is a competent arthropod vector of chikungunya virus (CHIKV). The rate at which the virus disseminate in the vector is limited by temperature of their environment which can be an important determinant of geographical and seasonal limits to transmission by the arthropods in the tropics. This study investigated the vector competence of Ae. aegypti for CHIKV at ambient temperature of 32 and 26 °C (Coastal and Western Kenya respectively) reared at Extrinsic Incubation Temperature (EIT) of 32 and 26 °C that resembles those in the two regions. Methods: Ae. aegypti eggs were collected from coastal and Western …

Can Climate-Driven Change Influence Silicon Assimilation By Cereals And Hence The Distribution Of Lepidopteran Stem Borers In East Africa?, P. A. Calatayud, E. Njuguna, S. Mwalusepo, M. Gathara, G. Okuku, A. Kibe, B. Musyoka, D. Williamson, G. Ong'amo, G. Juma, T. Johansson, S. Subramanian, E. Gatebe, B. Le Ru

All Peer-Reviewed Publications

In East Africa, lepidopteran stemborers such as Chilo partellus and Busseola fusca are major constraints to production of maize, which is the main staple food crop in the region. Cereals depend on silicon (Si)-based defences to fight off herbivores. Using altitudinal ranges in the East African highlands as ecological surrogates for inferring climate change, it was shown that Si concentrations in soil and maize decreased with altitude. This was attributed, in part, to low temperatures at high altitudes, which negatively affected Si assimilation by maize. Experiments showed that B. fusca was more susceptible to Si than C. partellus. Hence the …