Supercooling capacity and cryoprotectants of overwintering larvae from different populations of Holcocerus hippophaecolus.

ABSTRACT

BACKGROUND: Holcocerus hippophaecolus is the most serious pest occurred in seabuckthorn forest of three north areas. OBJECTIVE: The primary aims of the current study were to explore the physiological mechanisms and adaptability of H. hippophaecolus to low temperatures. MATERIALS AND METHODS: Assessing supercooling point, freezing point, and cryoprotectants of different larval instars from three different populations. RESULTS: Supercooling capacity of larvae from the 8-13 instar groups was relatively independent of temperature and other indicators such as latitude. Larvae from the 14-16 instar groups were sensitive to temperature and latitude, with generally lower limits and a wider range of SCPs than those of the other instar groups. CONCLUSION: For each population, the differences in the supercooling capacity of different instar stages for the identical period were not significant. The metabolism of fat and glycogen might not be the primary factors affecting the supercooling capacity.