关键词: 桃小食心虫, 越冬, 耐寒性, 过冷却点, 生化物质, 动态变化

Abstract: To elucidate the difference of cold-resisitant substances in overwintering cocooned and non-cocooned larvae of the peach fruit moth, Carposina niponensis Walsingham, cold tolerance of the overwintering larvae was investigated, and their supercooling capacity, water content, total fat content, total protein content and total sugar content were measured respectively. The results showed that the supercooling point (SCP), freezing point (FP), water content, total protein content and total sugar content of cocooned and non-cocooned larvae decreased from October to February of the next year. The water content of non-cocooned larvae increased continuously during the winter, and reached the highest level (61.42%) in February. The water content of non-cocooned larvae was higher than the cocooned larvae in the whole winter. The total sugar content of non-cocooned larvae decreased continuously during the whole overwintering period, and reached the lowest level (0.65 μg/mg) in February. The total sugar content of non-cocooned larvae was significantly lower than the cocooned larvae in the whole winter. There was no significant difference in total protein and total fat contents between the cocooned and non-cocooned larvae, respectively (P>0.05). The higher water content and lower sugar content of non-cocooned larvae might cause them fail to overwinter successfully.

Key words: Carposina niponensis, overwintering, cold-resistance, supercooling point (SCP), biochemical substances, dynamic change