Study on biological characteristics and spread trend of Tomostethus nigritus (Fabricius)

In order to clarify the biological characteristics and spread trend of Tomostethus nigritus (Fabricius), the life history, living habits, effective accumulated temperature and diffusion trend of this insect were basically clarified through field observation and indoor breeding in the past three years. The results showed that: (1) T. nigritus (Fabricius) occurred once a generation every year, and a large number of adults emerged in early March every year. Larvae gathered in late March to early April and damaged the leaves of osmanthus flowers, and the old larvae overwintered in the soil; (2) The identification characteristics of each insect stage were described, and specific control suggestions were put forward according to its occurrence law. (3) The developmental zero temperatures of pupae, adults, eggs and pre-cocoon forming larvae were 5.23℃, 10.13℃, 9.56℃ and 6.40℃, respectively, and the effective accumulated temperatures were 91.30 d·℃, 14.58 d·℃, 44.93 d·℃ and 95.21 d·℃, respectively. (4) The insect mainly spreads along adjacent roads, and the suitable altitude is 5 00 m~1 200 m.