Biological characteristics and integrated management of Pachyrhinus yasumatsui (Coleoptera: Curculionidae)

Pachyrhinus yasumatsui (Coleoptera: Curculionidae) is an important pest of jujube in China. The weevil adults mainly feed on jujube buds and young leaves. When the population breaks out, the newly germinated jujube buds are eaten clean, leading to bare and withered fruit-bearing spurs. The feeding of P. yasumatsui forces the tree to consume a large amount of nutrients to sprout again, and only a small amount of bitter jujube fruit is produced, which seriously reduces the yield and quality of jujube crops, and causes huge economic losses to the jujube area. In order to scientifically and effectively control the damage caused by P. yasumatsui, researchers have made many advances in the morphological feature, distribution and damage patterns, individual development and life cycle, spacial distribution and genetic diversity, antennal sensilla and olfactory mechanism, and integrated control techniques. Currently, P. yasumatsui has been found in all jujube-growing regions of northern China. The damage caused by P. yasumatsui has characteristics of aggregation and explosiveness, making prevention and control quite challenging. The early prevention and control of P. yasumatsui mainly focused on agricultural prevention and control measures such as deep ploughing jujube orchards, timely irrigation, and paving plastic film. Sticking insect glue on the trunk was the main physical control measure to control P. yasumatsui, but chemical control is still the most important and effective prevention and control method to reduce the population density of the weevils. In recent years, the host-oriented chemical communication mechanism of P. yasumatsui, which is mediated by the volatiles of jujube, has attracted attention and concern. Some biologically active semiochemicals and olfactory molecular mechanisms have been analyzed, which provides a basis for the development of biological control technology for P. yasumatsui based on plant-derived attractants. This article reviews the current research on P. yasumatsui and anticipates future development trends. It aims to provide reference materials and theoretical basis for the green prevention strategies and scientific management of P. yasumatsui.