Abstract: To examine the differences in responses of the invasive golden apple snails at various life-history stages to acidic stress, the survival behavior and lethal effect of Pomacea canaliculata with shell height of 5, 10, 15, 20, 25, 30, 40, 50, and 60 mm in the acidic environment were examined. At pH≥4, movement and spawning of P. canaliculata was normal within seven days, and its reactions to the acidic stress became stronger with the increases of acidity. The median lethal time (LT₅₀) at pH=2.0 was less than that at pH=3.0. The LT₅₀ was the largest in the 40 mm shell height group (22.95 h), while it was the smallest in the 60 mm shell height group (13.55 h). There were significant differences in mortality among different shell height groups (P<0.001) and among different time (P<0.001). The interaction between shell-height effect and timeeffect was significant (P<0.001). At pH=2.0, the mortality rates of P. canaliculata with shell height of 40 mm at 24 h and 30 h were 46.67%±11.50% and 53.33%±11.50%, respectively, being significantly lower than those in other groups. At pH=3, the mortality of P. canaliculata with shell height of 60 mm was 86.67%±11.50% at 24 h. The mortality (66.67%±11.50%) of P. canaliculata with shell height of 40 mm was lower than the other groups at 30 h. The mortality of P. canaliculata in the groups of 5, 10, 20 and 60 mm was 100%. Therefore, the variation of the snails’ acid resistance was parabolic shaped, with an increase following a decline along with the snail’s development. By illustrating the responses of the snails at various developmental stages to acidic stresses, our results would help explain their ecological adaptation mechanism and invasion strategy from the view of life-history.

Key words: water spinach (Ipomoea aquatica),  , cultivar, rhizosphere, soil chemical characteristics, low Cd accumulation.