Resistance of cabbage (Brassica oleracea capitata group) populations to Mamestra brassicae (L.)

Abstract

Cabbage (Brassica oleracea capitata group) crops are severely damaged by different insect pests. Larvae of lepidopterous pests feed on foliage, creating large holes in leaves. Cabbage plants can tolerate some feeding damage before head formation. However, as larvae grow, they move to the center of the plant, boring into the cabbage head and resulting in head deformation, which reduce product marketability (Shelton et al., 1982). Feeding damage also increases the plants’ susceptibility to diseases. The use of resistant cultivars could benefit growers by reducing insecticide use and decreasing the rate at which insects develop resistance to insecticides. Insect resistance in Brassica crops is well documented. Most studies have focused on cabbage resistance to three major lepidopterous pests: Pieris rapae (L.), Plutella xylostella (L.), and Trichoplusia ni (Hübner) (Dickson and Eckenrode, 1980; Hoy and Shelton, 1987) and few studies have been conducted to find germplasm resistant to other important pest such as Mamestra brassicae (L.) (Picoaga et al., 2003). However, until now, breeding for resistance to lepidopterous insects has yielded very little success. The objective of this work was to evaluate the performance of cabbage populations to leaf damage by lepidopterous pests in northwestern Spain.