Molecular and Chemical Ecology

The Experimental Biology Research Group is devoted to understanding the genes and metabolites that regulate ecological interactions. Our experimental system includes plants, herbivore insects, and herbivore natural enemies such as predators and entomopathogenic nematodes. Our research has lately focused on Photorhabdus bacteria, the symbionts of Heterorhabditis entomopathogenic nematodes. In particular, we have investigated their phylogenetic relationships, implemented methods to identify them rapidly, and improved their biological control potential.

More recently, we have started to unravel the adaptive value of one of its most prominent traits: Bioluminescence. Photorhabdus bacteria produce light when they multiply inside their host insects. Therefore, the organisms that are infected by Photorhabdus bacteria are bioluminescent. What are the benefits that could explain the occurrence and prevalence of this trait? This is one of the questions that we are currently tackling by studying the regulatory potential of Photorhabdus bioluminescence in belowground multi-trophic interactions.

  • Entomopathogenic potential of bacteria associated with soil-borne nematodes and insect immune responses to their infection
    A Loulou, M Mastore, S Caramella, AH Bhat, MF Brivio, RAR Machado, Sadreddine Kallel
    PloS one 18 (1), e0280675, 2023,

  • Comparative morphological and molecular analyses of Acrobeloides bodenheimeri and A. tricornis Cobb, 1924 (Rhabditida, Cephalobidae) from Tunisia
    AH Bhat, A Loulou, J Abolafia, RAR Machado, S Kallel
    Nematology 1 (aop), 1-20, 2022

  • Virulence and reproductive potential of Indian entomopathogenic nematodes against the larvae of the rice meal moth
    TH Askary, AH Bhat, RAR Machado, MJ Ahmad, MMM Abd-Elgawad, ...
    Archives of Phytopathology and Plant Protection, 1-13, 2022,

  • Early land plants: Plentiful but neglected nutritional resources for herbivores?
    A Duhin, RAR Machado, TCJ Turlings, G Röder
    Ecology and Evolution 12 (12), e9617, 2022

  • Morphological and molecular identification of Trichoderma asperellum isolated from a dragon fruit farm in the southern Philippines and its pathogenicity against the larvae of …
    R Sebumpan, KR Guiritan, M Suan, CJ Abapo, AH Bhat, RAR Machado, ...
    Egyptian Journal of Biological Pest Control 32 (1), 1-7, 2022

  • Chemical Ecology of Nematodes
    RAR Machado, SH von Reuss
    CHIMIA 76 (11), 945-945, 2022

  • Redescription and molecular characterisation of Panagrolaimus labiatus (Kreis, 1929) Andrássy, 1960 (Rhabditida, Panagrolaimidae) from India and proposal of P. burdwanensis
    K Yadav, AH Bhat, J Abolafia, RAR Machado, SM Wani, AK Chaubey
    Nematology 25 (2), 151-168, 2022

  • Photorhabdus antumapuensis sp. nov., a novel symbiotic bacterial species associated with Heterorhabditis atacamensis entomopathogenic nematodes
    C Castaneda-Alvarez, RAR Machado, P Morales-Montero, A Boss, A Muller, S Prodan, A Zamorano, E San-Blas, V Půža, E Aballay
    International Journal of Systematic and Evolutionary Microbiology 72 (10) 2022,

  • Sequestration of cucurbitacins from cucumber plants by Diabrotica balteata larvae provides little protection against biological control agents
    P Bruno, CCM Arce, RAR Machado, G Besomi, A Spescha, G Glauser, C Jaccard, B Benrey, Ted CJ Turlings
    Journal of Pest Science, 1-15, 2022
  • Potential of Oscheius tipulae nematodes as biological control agents against Ceratitis capitata
    A Loulou, M M’saad Guerfali, A Muller, AH Bhat, J Abolafia, Ricardo AR Machado, S Kallel
    Plos one 17 (6), e0269106  2022
  • Comparative Screening of Mexican, Rwandan and Commercial Entomopathogenic Nematodes to Be Used against Invasive Fall Armyworm, Spodoptera frugiperda
    P Fallet, L De Gianni, RAR Machado, P Bruno, JS Bernal, P Karangwa, J Kajuga, B Waweru, D Bazagwira, T Degen, S Toepfer, Ted CJ Turlings
    Insects 13 (2), 205 2022
  • Steinernema africanum n. sp.(Rhabditida, Steinernematidae), a New Entomopathogenic Nematode Species Isolated in the Republic of Rwanda
    RAR Machado, AH Bhat, J Abolafia, E Shokoohi, P Fallet, TCJ Turlings, ...
    Journal of Nematology 54 (1) 2022
Ricardo Machado Uni Neuchatel

Dr. Ricardo A. R. Machado
University of Neuchâtel
Institute of Biology
2000 Neuchâtel

phone: +41 32 718 3046

  • Chemical and molecular aspects of plant-herbivore-natural enemy interactions
  • Ecology of Photorhabdus entomopathogenic bacteria (EPB)
  • Ecology of Heterorhabditis entomopathogenic nematodes (EPN)
  • Foraging behaviour of Diabroticine larvae
  • Insect resistance to EPB and EPN
  • Plant responses to herbivory
  • Ecology
  • Microbiology
  • Molecular Biology
  • Plant-Animal Interactions
  • Plant-Microbe Interactions