Mortality of eggs, larvae and pupae and larval dispersal of the cabbage moth, Mamestra brassicae, in white cabbage in south‐eastern Norway

Abstract

The mortality of eggs, larvae and pupae and larval dispersal of the cabbage moth, Mamestra brassicae (L.) (Lepidoptera: Noctuidae) was investigated in a series of small‐scale field experiments in white cabbage, Brassicae oleracea var. capitata (L.), and in the laboratory during 1990–1992 in south–eastern Norway. The highest mortality was found in young larvae and in hibernating pupae. In 1990, larval mortality in the first instar was 80% (range 9–97% for the individual cohorts). Most larvae died within the first 1–3 days after hatching. The dispersal activity during these days was high, and failure to establish feeding sites and predation were probably the main mortality causes. Pupal mortality during winter was 90% on average for 1990–1993 (range 81–100%). The main mortality factor was probably unfavourable weather conditions, and indications of cold stress were found. The impact from parasitoids and diseases was generally low. Trichogramma semblidis (Aurivillius) (Trichogrammatidae) was reared from M. brassicae eggs in very low numbers in 1991. Larval parasitism increased from < 1% in 1990 to almost 24% in 1992, and was almost totally caused by the braconids Microplitis mediator (Haliday) and Aleiodes (Aleiodes) sp. Predation of frozen larvae on the soil surface was 75% on average (range 63–96%) during 1990–1992 in first instar larvae and decreased gradually with larval age. The consumption rates of Philonthus atratus (Gravenhorst) (Staphylinidae) and the carabids Bembidion tetracolum (Say), Pterostichus melanarius (Illiger) and Harpalus rufipes (Degeer) on M. brassicae eggs and larvae were investigated in non‐choice experiments in the laboratory. A preliminary survival model based on estimates of the mortality factors identified in this study is presented.

Defence mechanisms of Brassicaceae: implications for plant-insect interactions and potential for integrated pest management. A review

“…• N (Johansen, 1997). The Bertha armyworm, also referred to as the 'Miller Moth' or 'climbing cutworm', is native to North America and is a pest of oilseed and canola production in the northern Great Plains (Ulmer, 2002;Knodel and Ganehiarachchi, 2008).…”

“…The mortality of eggs, larvae, pupae and larval dispersal of the cabbage moth on white cabbage (B. oleracea var. capitata) was investigated in a series of small-scale field experiments and in the laboratory (Johansen, 1997). The highest mortality was found in young larvae and in hibernating pupae.…”

Rearing of Microplitis mediator (Hymenoptera: Braconidae) and its host Mamestra brassicae (Lepidoptera: Noctuidae)

“…The cabbage moth Mamestra brassicae (Linnaeus, 1758) (Le pi doptera: Noctuidae) is widely distributed throughout Asia and Europe (Johansen, 1997) and one of the major pests of cabbage in Europe (Finch & Thompson, 1992). Its polyphagous larvae feed mainly on cabbage (Brassica oleracea L., Brassicaceae) and other plants in the genus Brassica, but also on tomato, beet, on ion and some flowers and forest trees (Hill, 1987).…”

“…Its polyphagous larvae feed mainly on cabbage (Brassica oleracea L., Brassicaceae) and other plants in the genus Brassica, but also on tomato, beet, on ion and some flowers and forest trees (Hill, 1987). The larvae of M. brassicae are attacked by braconid wasps (Johansen, 1997), among which the solitary larval parasitoid, Microplitis mediator (Haliday, 1834) (Hymenoptera: Braconidae), is the most impor tant (Bianchi et al, 2005;Lauro et al, 2005). It is a generalist endoparasitoid that is reported from approximately 40 different noctuid hosts (Mir Khan, 1999).…”

Seasonal dynamics of the cabbage armyworm (Mamestra brassicae [L.]) and the bright-line brown-eyes moth (Mamestra oleracea [L.]) in Slovenia

“…Some authors claim that this pest can have up to three generations per year (Oku, Kobayashi 1974). In northern Europe, it was reported that the cabbage armyworm is a univoltine species (Johansen 1997;Metspalu et al 2004). In central Europe, the bright-line brown-eyes moth also has two generations (Čamprag, Jovanić 2005).…”