. Cooperative economic insect report. Beneficial insects; Insect pests. - 874 - Life History and Habits: The life history of Mamestra brassicae as recorded in Bulgaria is as follows: The female deposits its eggs in 6 to 28 clusters, 15 to 188 per cluster. Females may deposit from 438 to several hundred eggs, generally on the underside of the leaf. Eggs hatch in 6 to 9 days. The larvae pass through 5 molts in 25 to 30 days, feeding on the leaves of the host plants or in some instances into the heads and stalks. Pupation takes place in the soil, 5 to 6 cm. deep. The pupal period during the summe
. Cooperative economic insect report. Beneficial insects; Insect pests. - 874 - Life History and Habits: The life history of Mamestra brassicae as recorded in Bulgaria is as follows: The female deposits its eggs in 6 to 28 clusters, 15 to 188 per cluster. Females may deposit from 438 to several hundred eggs, generally on the underside of the leaf. Eggs hatch in 6 to 9 days. The larvae pass through 5 molts in 25 to 30 days, feeding on the leaves of the host plants or in some instances into the heads and stalks. Pupation takes place in the soil, 5 to 6 cm. deep. The pupal period during the summer averages about 27 days before emergence of the new generation. Hibernation takes place in the pupal stage. In Bulgaria two generations a year are normal, sometimes a partial third generation developing, while in Scotland one generation is usual with a partial second generation sometimes being produced. Characteristic damage to disc-shaped flowers involves feeding on the outer circumference at first and then uniformly, all around, gradually working inwards until nothing is left but the central disc of flowers. Description: The adult wing expanse is about 44 mm. Forewing dark brown irrorated with gray; many blackish streaks and marks present. Subterminal line not defined by whitish on inner side. This character separates M. brassicae from M. configurata, a North American species which has subterminal line prominently defined by whitish on inner side. Orbicular spot is distinctly defined by black. Hindwing brown, pale at base with whitish fringe. Thorax color same as forewings. Abdomen brown with more or less distinct tufts down back, tip of abdomen distinctly tufted. Legs brown and very hairy at base. Fore tibia with long terminal claw. This character separates M. brassicae from the species of closely related genus Polia. Larvae vary greatly in color when mature, but always green when young. Mature larvae are about 30 mm. long and have three light lines with slanting black mark
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Keywords: ., bookcentury1900, booksubjectbeneficialinsects, booksubjectinsect
