Validation of associations between plant traits and thrips damage in cabbage

Abstract

When cabbage is cultivated for storage in the Netherlands, it is usually harvested around mid-October. This type of cabbage crop may be severely damaged by thrips (Thrips tabaci). The thrips population on the plants and the more severe symptoms develop mostly during September and October. Also during cold storage symptoms continue to develop. The damage caused by thrips is due to the symptoms that develop after feeding, which are small callus-like growths that will turn brownish after some time and which may cover substantial amounts of leaf area. Large differences exist between cabbage varieties in their susceptibility to thrips damage. Based on several years of field trials with more than 40 commercial varieties and gene bank accessions it was established that a large proportion of the variation for thrips damage could be explained by a few plant traits: the amount of leaf surface wax, earliness and Brix (Voorrips et al, 2008). Using an F3-line population derived from a cross between a high-damage, low-wax, high-Brix, earlier heading and a low-damage, high-wax, low-Brix, later heading accession we determine whether the relations between plant traits and thrips damage can be confirme