Co-expression of the proteinase inhibitors oryzacystatin I and oryzacystatin II in transgenic potato alters Colorado potato beetle larval development.
Colorado potato beetle (CPB; Leptinotarsa decemlineata Say, Coleoptera: Chrysomelidae) has shown a remarkable adaptability to a variety of control measures. Although oryzacystatin I and II (OCI and OCII) have potential in controlling pests that use cysteine proteinases for food digestion, expression of a single OC gene in potato exhibited a minimal or no effect on CPB fitness traits. The aim of this study was to examine the effect of coexpressed OCI and OCII in potato (Solanum tuberosum L.) cultivars Desiree, Dragačevka and Jelica on CPB larvae. Growth parameters, consumption rates and food utilization, as well as activity of proteases of CPB larvae were assayed. Second and third instar larvae fed on transformed leaves molted earlier and had higher relative growth and consumption rates than larvae fed on nontransformed leaves, while efficiency of food utilization was unaffected. In contrast, fourth instar maximum weight gain and amount of leaves consumed were about 20% lower for the larvae fed on transgenic potato. Analysis of total protease activity of third instar larvae revealed reduction in overall proteolytic activity measured by azocasein hydrolysis, accompanied with inhibition of cysteine proteinase activity 24 h after ingestion of potato leaves expressing OCI and OCII. However, after long-term feeding on transformed leaves proteolytic activities of larvae became similar to the controls. Although feeding on OCI/OCII leaves did not affect larval survival, coexpression of OC genes reduced the development time and thus significantly decreased plant damage caused by CPB larvae.
Institute for Biological Research "Siniša Stanković", University of Belgrade, Bulevar despota Stefana 142, Belgrade, Serbia.
Aleksandar
A
Cingel
Institute for Biological Research "Siniša Stanković", University of Belgrade, Bulevar despota Stefana 142, Belgrade, Serbia.
Jelena
J
Savić
Institute for Biological Research "Siniša Stanković", University of Belgrade, Bulevar despota Stefana 142, Belgrade, Serbia.
Jelica
J
Lazarević
Institute for Biological Research "Siniša Stanković", University of Belgrade, Bulevar despota Stefana 142, Belgrade, Serbia.
Tatjana
T
Ćosić
Institute for Biological Research "Siniša Stanković", University of Belgrade, Bulevar despota Stefana 142, Belgrade, Serbia.
Martin
M
Raspor
USDA-ARS, Molecular Plant Pathology Laboratory, 10300 Baltimore Avenue, Beltsville, Maryland, USA.
Ann
A
Smigocki
Institute for Biological Research "Siniša Stanković", University of Belgrade, Bulevar despota Stefana 142, Belgrade, Serbia.
Slavica
S
Ninković
D000818:Animals; D001517:Coleoptera / Q000187:drug effects* / Q000254:growth & development; D015891:Cystatins / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology*; D015853:Cysteine Proteinase Inhibitors / Q000378:metabolism / Q000494:pharmacology*; D007814:Larva / Q000187:drug effects / Q000254:growth & development; D030821:Plants, Genetically Modified / Q000235:genetics / Q000378:metabolism*; D011198:Solanum tuberosum / Q000235:genetics / Q000378:metabolism*
D015891:Cystatins; D015853:Cysteine Proteinase Inhibitors
Colorado potato beetle; Solanum tuberosum L.; gene stacking; oryzacystatin I and II; proteinase inhibitors