Detailed Analysis of the Occurrence Patterns of the Jujube Leafroller

The jujube leafroller occurs in 4 to 5 generations per year, with overlapping generations, making it difficult to control. It overwinters as pupae in the cracks of old jujube bark. In March to April of the following year, adults emerge, mate 2 to 4 days after emergence, and lay eggs mostly on jujube branches. The first-generation larvae occur during the bud break and leaf expansion stage, spinning silk to bind leaves, hang down, and feed on tender leaves. From the second generation onward, they not only damage leaves but also bore into and gnaw jujube fruit. Except that the overwintering generation mostly spins cocoons and pupates inside leaf clusters, the mature larvae of the overwintering generation often also spin cocoons and pupate inside the bark to protect against cold and to overwinter. When disturbed, the larvae spin silk and drop down, wriggling wildly when touched.