Yield loss quantification and economic injury level estimation for the carpophagous generations of the European grapevine moth Lobesia botrana Den. et Schiff. (Lepidoptera: Tortricidae)

Abstract

Yield loss in grapevine caused by the two carpophagous generations of the grapevine moth, Lobesia botrana Den. et Schiff. (Lepidoptera: Tortricidae), was determined during 1995 – 1999 in a vineyard of the wine production variety ‘Savvatiano’ situated at Spata, Attiki, Greece. Concurrently, an estimate of the economic injury level (EIL) was obtained for each generation and expressed as both pest density and damage level. Damage level and larval densities were monitored and injury tolerance of the variety was also taken into account for calculating yield loss. Yield loss was found to be substantial, in particular for the second carpophagous generation, amounting to 2767 kg/ha or 13.3% for the first and 5685 kg/ha or 27% for the second carpophagous generation. During the survey, the EIL expressed as damage level was found to be one damaged berry/bunch for both generations, but when expressed as larval density it was nearly five times as high for the first (0.28 larvae/bunch) in contrast to the second carpophagous generation (0.06 larvae/bunch). These findings are discussed in the light of post-1999 changes in pest management costs.

Keywords:

• Grapevine
• Lobesia botrana
• yield loss
• economic injury level
• infestation
• damage
• integrated pest management

Acknowledgements

The author would like to thank Dr M. A. Jervis for reviewing the manuscript, Ms Vassiliki Kapothanassi for her contribution to the examination of the samples and the company Cambas SA for kindly granting the use of the vineyard over a number of years.