The peach fruitmoth.
Carposina niponensis Wlsm. (formerly known as C. sasakii Mats.) on peach trees is widely distributed in north-western and western China, Korea and Japan, and in the USSR it occurs in the Maritime region, Khabarovsk and the south of Sakhalin, where it was noted in 1978. The moth is subject to both external and internal quarantine regulations. All stages of the moth are described in some detail, with a figure illustrating the larval chaetotaxy, and its bionomics are described. The larvae overwinter in thick cocoons, which they spin in the soil beneath the trees in autumn at depths of 5-13 cm. They are resistant to low temperatures during this period, but in spring, when the temperature rises above 15 deg C, they come up to the surface, where they pupate in light summer cocoons. The adults emerge in 10-15 days, remain motionless on vegetation for the first few days but become active at night. Oviposition begins 2-3 days after emergence of the females, which lay 40-220 eggs each, mainly in the fruit calyxes. Winter mortality does not exceed 50-55%, which has little effect on population numbers, and in the Soviet Far East the females lay an average of 100-120 eggs each, though oviposition ceases at temperatures below 16 deg C. The egg stage lasts 6-9 days, the most favourable temperatures being 25 deg C with 75-85% RH. The larvae enter the fruits and feed for about a month. They then enter diapause, depending on daylength, the critical length being (at 40 deg N.lat.) 14 h 20 m at 25 deg C. The lower thresholds in the Soviet Far East are 11 deg C for the eggs, 15 deg C for the larvae and 11 deg C for the pupae. There are usually 2 generations a year in most regions and even 3 in the south. High temperatures in May, June and July favour development, provided that light conditions are also favourable, and there are later summer generations. If the temperature is less favourable for egg hatching, part of the population develops in 1 or 2 generations, but the other part is delayed and enters hibernation. Apple, pear, and apricot are also infested. Further details of life-history are given, and its possible behaviour in other parts of USSR is considered.