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Collaborative Opportunity for Research on Insect and Disease Resistance in Plants


Plant Research International has been involved in insect and disease resistance research for the past fifteen years. We have a strong track record on the use of Bt toxins, protease inhibitors and metabolic engineering to achieve resistance against pests and pathogens in plants.

Among our recent achievements in the resistance field are:

  1. novel genes (protease inhibitors and monoterpene synthases) active against sucking insect pests such as thrips and aphids
  2. broad-range Bt hybrid toxins active against both lepidopteran and coleopteran insects
  3. monoterpene synthase genes with activity against fungal pathogens in planta.

Several of these findings were patented and are now in development with licensed companies.

Vision / strategy

Insect resistance is worldwide next to herbicide resistance the most successful and relevant transgenic trait in plants. Currently Bt toxins dominate the field. However Bt toxins are only active against lepidopteran and coleopteran pests and so far no good control over sucking pests has been achieved. We have studied endogenous plant defense at two different levels: the antimetabolic digestive protease inhibitors and the volatile terpenoids. Both traits are very relevant to plant defense against insects and in addition terpenoids also play an important role as antimicrobial agents. Our research demonstrates that we are able to change the plant volatile emissions and we have engineered protease inhibitors in such a way that plants become resistant against several different sucking insect pests and fungal infections.

Business opportunities

We have several patents relevant to insect and disease resistance in plants. This technology is open for licensing. Usually such license contracts are carried out as a joint development program in order to bring such products to the market.

PRI strategy in developing this field:

  • PRI is seeking long-term collaborations with commercial partners to jointly co-develop market-ready products for exploitation and commercialization.
  • IP Strategy: where relevant from commercial point of view, patent protection is sought. PRI aims at developing joint IP in its collaborative research programmes. Where relevant, industrial partners will get access to existing IP belonging to PRI in the field of interest.

Track record

Some key references (additional references are available upon request)

Protease inhibitors

  • Outchkourov NS, de Kogel J, Schuurman-de Bruin A, Abrahamson M, Jongsma MA (2004) Specific cysteine protease inhibitors act as deterrents of Western flower thrips Frankliniella occidentalis (Pergande) in transgenic potato. Plant Biotechnology Journal 2: 439-448.
  • Outchkourov, N.S., de Kogel, W.J., Wiegers, G.L., Abrahamson, M. and Jongsma, M.A. (2004) Engineered multidomain cysteine protease inhibitors yield resistance against western flower thrips ( Frankliniella occidentalis ) in greenhouse trials. Plant Biotechnology Journal 2: 449-458
  • Ceci, L.R., Volpicella M., Conti S., Gallerani R., Beekwilder M.J.,   Jongsma M.A. (2003) Selection by phage display of a mustard chymotrypsin inhibitor toxic to pea aphid. Plant Journal 33: 557-566
  • Jongsma, M.A., Bakker, P.L., Peters, J., Bosch, D., Stiekema, W.J.. (1995) Adaptation of Spodoptera exigua larvae to plant proteinase inhibitors by induction of gut proteinase activity insensitive to inhibition. Proc. Natl. Acad. Sci. USA 92: 8041-8045 (citation 131x)

Metabolic engineering

  • Mercke, P., I.F. Kappers, F.W.A Verstappen, O. Vorst, M. Dicke and H.J. Bouwmeester. Combined transcriptome and metabolome analysis reveals genes involved in spider mite induced volatile formation in cucumber plants. Plant Physiol , in press
  • Balkema-Boomstra, A.G., S. Zijlstra, F.W.A. Verstappen, H. Inggamer, P.E. Mercke, M.A. Jongsma and H.J. Bouwmeester, 2003. Role of cucurbitacin C in resistance to spidermite (Tetranychus urticae) in cucumber (Cucumis sativus L.). J. Chem. Ecol. 29: 225-235
  • Aharoni, A., A.P. Giri, S. Deuerlein, F. Griepink, W-J. de Kogel, F.W.A. Verstappen, H.A. Verhoeven, M.A. Jongsma, W. Schwab and H.J. Bouwmeester, 2003. Terpenoid metabolism in wild-type and transgenic Arabidopsis plants. The Plant Cell 15: 2866-2884
  • Bouwmeester, H.J., F.W.A. Verstappen, M.A. Posthumus and M. Dicke, 1999. Spider mite-induced (3S)-(E)-nerolidol synthase activity in cucumber and Lima bean. The first dedicated step in acyclic C11-homoterpene biosynthesis. Plant Physiology 121: 173-180.

Bt toxins

  • de Maagd, R.A., Bravo, A., Berry, C., Crickmore, N. and Schnepf, H.E. (2003b) Structure, diversity and evolution of protein toxins from spore-forming entomopathogenic bacteria. Ann. Rev. Genet ., 37, 409-433.
  • Naimov, S., Dukiandjiev, S. and de Maagd, R.A. (2003) A hybrid Bacillus thuringiensis delta-endotoxin gene gives resistance against a coleopteran and a lepidopteran pest in transgenic potato. Plant Biotechnol. J. , 1, 51-57.
  • de Maagd, R.A., Bravo, A. and Crickmore, N. (2001a) How Bacillus thuringiensis has evolved specific toxins to colonize the insect world. Trends Genet. , 17, 193-199.
  • de Maagd, R.A., Bosch, D. and Stiekema, W.J. (1999a) Bacillus thuringiensis toxin mediated insect resistance in plants. Trends Plant Sci. , 4, 9-13.

Patent applications

  • Jongsma, M.A., Bosch, H.J., Stiekema, W.J., Gruden, K., Strukelj, B., Ritonja, A., Turk, V.(1997) “A method for plant protection against insects or nematodes”: WO9858068
  • Bouwmeester, H.J., J. Kodde and J-W. de Kraker, 1999. Sesquiterpenoid synthase genes and their use for influencing bitterness and resistance in plants. WO0055338
  • Aharoni, A., M. Jongsma, H. Verhoeven and H.J. Bouwmeester, 2001, Isoprenoid synthases, WO02064764
  • de Maagd, R.A. and Bosch, H.J. (2001). Bacillus thuringiensis hybrid toxins. WO0134811

For further information please contact either:
Euro Japan Marketing Limited
Phone: +81 3 3664 5062 • Email: •
Plant Research International B.V.
Phone: +31 317 47 7377 • E-mail:

For additional details please go to the PRI homepage or contact us.

Plant Research International is currently offering specific opportunities relating to: