The predatory capacity of Sycanus croceovittatus on Spodoptera frugiperda at different temperatures
Author of the article:WANG Ya-Nan, ZHAO Sheng-Yuan, HE Yun-Zhuan, WANG Gen-Song, HUANG Jian-Rong, TIAN Cai-Hong, LI Guo-Pi
Author's Workplace：Henan Key Laboratory of Crop Pest Control, Institute of Plant Protection, Entomological Radar Station Zero of Henan Province for Field Scientific Observation and Research, Henan Academy of Agricultural Sciences, Zhengzhou 450002, China
Key Words：Sycanus croceovittatus; Spodoptera frugiperda; temperature; predation
Abstract：
[Objectives] To determine the effect of temperature on the predation of Sycanus croceovittatus on Spodoptera frugiperda. [Methods] Second and 5th instar nymphs, females and males of S. croceovittatus were allowed to prey on different densities of 2nd instar S. frugiperda larvae at 15, 20, 25, 30 and 35 ℃. Predation was observed and the amount of prey was calculated to determine the predation function at each temperature. [Results] Predation was significantly affected by temperature; predation was low at 15 ℃ and 20 ℃ ，but at 25-35 ℃ predation by 2nd and 5th instar S. croceovittatus nymphs, and by adults approximated the Holling Ⅱ functional response model. Maximum predation by 2nd and 5th instar nymphs and adult females and males (12.05, 66.67, 100.00, and 52.63, respectively, handling time 0.08, 0.02, 0.01 and 0.02 d)were observed at 30 ℃. [Conclusion] The highest level of predation by S. croceovittatus on S. frugiperda was observed at 30 ℃.