Trypsin protease inhibitor activity is not a good proxy for defence against Oligonychus ilicis (Acari: Tetranychidae) in Coffea canephora (Gentianales: Rubiaceae)

Abstract

Oligonychus ilicis is one of the most important pests that causes injury to the Robusta Coffee leaves, but no data is available on the production of protease inhibitors (PIs) in Coffea. canephora plants, either sensitive or resistant to O. ilicis. This work aimed to determine the C. canephora genotypes susceptible and resistant to O. ilicis and the activity of PIs in these genotypes. In the first trial, we assessed the susceptibility of 14 C. canephora genotypes to O. ilicis and found considerable variation. The Significant differences in the fecundity, net reproductive rate and intrinsic rate of population increase were observed among different genotypes of C. canephora. In the second one, we assessed the activity of PIs in leaves of the 14 C. canephora genotypes damaged and non-damaged by O. ilicis. The contents of the PI were influenced by genotypes, presence of mites and the interaction of the both factors. In the susceptible genotypes, an increase in the activity of trypsin-like PIs is predominant, while in the resistant genotypes a reduction in this activity predominates. These findings indicate that trypsin PI activity is not a good proxy for defence against O. ilicis.

Keywords:

• PIs
• mite
• Tetranychidae
• Robusta Coffee
• Life Tables

Acknowledgements

The authors would like to thank the National Council for Scientific and Technological Development (Conselho Nacional de Desenvolvimento Científico e Tecnológico – CNPq) and the Brazilian Federal Agency for the Support and Evaluation of Graduate Education (Coordenação de Aperfeiçoamento de Pessoal de Ensino Superior – CAPES).

Additional information

Funding

The authors would like to thank the Research Support Foundation of the State of Minas Gerais (Fundação de Amparo à Pesquisa do Estado de Minas Gerais – FAPEMIG) and the National Program on Coffee Research and Development (Programa Nacional de Pesquisa e Desenvolvimento do Café – PNP&D Café) for financially supporting this research.