Abstract: In order to achieve the massive rearing and release of the alligator weed flea beetle, Agasicles hygrophila, for controlling the damage of alligator weed, Alternanthera philoxeroides, we explored and established the method and work flow of massively rearing A. hygrophila in the laboratory. Our method and work flow involve the combination of the following steps in sequential order: hatching eggs by putting the leaves with eggs into rearing dish or the seedlings with eggs into jars containing water; rearing the 1st, 2nd, 3rd instar larvae and the adults of A. hygrophila, and having the adults lay eggs by putting the plants of A. philoxeroides into rearing box; helping A. hygrophila to complete the pupation and eclosion process by using live stems planted in a bucket filled with a layer of thin wet soil. The adults of A. hygrophila were able to feed, copulate and lay eggs around the clock. The prophase of egg-laying was about 4-5 d and the peak phase of egglaying was from the 7th to 24th day after eclosion. The average egg mass and egg number per female was 21.08 and about 570 in total in rearing box, respectively. The average egg mass on one leaf of alligator weed was 4.28 with the approximately same number on the back of leaf when reared in rearing box. The average egg mass on one leaf of A. philoxeroides was 1.46 and the eggs were mainly laid on the back of leaf when reared in cage. The ratios of A. hygrophila hatched eggs obtained from rearing box and cage were 94.02% and 92.50%, respectively. The 1st, 2nd, 3rd instar larva and the adult could be reared in high density using fresh broken seedlings of A. philoxeroides in rearing box. However, the pupation could only be completed smoothly using live stem planted in wet soil. We found that the periods from early 1st instar larva transferring to fresh plants (or leaves) and from fully developed 3rd instar larva in transition to pupation were both the critical phases for successful high-density rearing. The optimal density of fully developed 3rd instar larvae in transition to pupation was 8 individuals per plant, while the optimal density of egg-laying females was 5 individuals per plant.

Key words: Alternanthera philoxeroides, Agasicles hygrophila, biology, massive rearing and reproduction, decreasing district disaster