Ecological strategies of Hyphantria cunea (Lepidoptera: Arctiidae) response to different larval densities

Population density is an essential factor affecting the life history traits of insects and their trade-off relationships, as increasing intensifies intraspecific competition. It decreases average resources available to individuals within a population, morphology, physiology, behavior, fitness. The fall webworm, Hyphantria cunea (Drury) (Lepidoptera: Arctiidae), has been invasive pest forest trees, ornamental plants, fruit trees in China for many years. larvae have typical aggregation habit before fourth instar keep spitting silk gather damaged leaves into webs. However, fitness H. response population remains unclear. In this study, critical biological parameters, food utilization, parameters different rearing densities were investigated. results showed that under high density, better performance, with faster development, higher survival rates, shorter generation time, but pupal weight female fecundity decreased increased. contrast, raised low developmental period was prolonged, mortality increased, while greater body size, observed. Both males females had similar development strategies may be more resistant crowding than males. conclusion, could adopt ecological against stress density. High result cycles rates. Conversely, low-density becomes longer fecundity. help determine possible outbreak mechanism develop effective monitoring forecasting measures .