Ecological characteristics of mulberry longicorn beetle, Apriona germari Hope, at the hibernation stage in mulberry fields.
To study the ecological characteristics of the cerambycid Apriona germari [A. germarii], mulberry branches with oviposition scars were collected from ten mulberry fields in various regions during hibernation. Its distribution was greatest in Kyunggi province with a distribution rate of 3.05% and lowest in Kyungnam province with a rate of 0.28%. The number of the oviposition scars per branch was one only in 87.7% of cases, with an average size of 2.38 cm in length, 1.45 cm in width and 0.34 cm in depth. The average diameter of scarred branches was 1.7 cm, ranging from 1.3 to 1.9 cm. The egg was long and elliptical in shape with a width of 2.32 ± 0.33 mm and a length of 6.60 ± 0.55 mm. The weight of the egg was 16.6 ± 2.94 mg and the colour of the newly oviposited egg was milky white, changing to deep brown with time. The weight and length of the newly hatched larva were 16.6 ± 2.4 mg and 6.36 ± 0.66 mm, respectively. Most of the larvae moved downwards inside the branch. Overwintering took place during the egg or larval stage, depending on region. The survival rate of the egg after hibernation was significantly low (6.6%), while for the larval stage it was remarkably high (91.2%).