Abstract: 【Aim】This study aims to clarify the effects of temperature on the body color of adults of Trichogramma spp.【Methods】Adults of ten species of Trichogramma wasps, including T. cacoeciae, T. embryophagum, T. pretiosum, T. chilonis, T. evanescens, T. ostriniae, T. dendrolimi, T. minutum, T. turkestanica and T. japonicum were reared at 18 and 30 ℃, respectively. And the RGB color mode was used as the body color judgment standard to compare the body color differences of adults of the 10 species of Trichogramma reared at 18 and 30 ℃.【Results】There were obvious differences in the body color of adults of the 10 species of Trichogramma reared at 18 and 30 ℃. The body colors of adults of 10 species of Trichogramma reared at 18 ℃ were darker than those reared at 30 ℃. Among them, T. cacoeciae adults showed the most obvious change in body color: the thorax was in yellowish brown and the abdomen was in dark brown at 18 ℃; however, the thorax and abdomen were in light yellow at 30 ℃. The adults of the 10 species of Trichogramma reared at 18 and 30 ℃ had obvious changes in the body color in their mesoscutum and scutellum, as well as the 1st-3rd segments of abdomen or the mid-abdomen. The RGB values of the body colors of adults of the 10 species of Trichogramma reared at 18 ℃ were significantly lower than those reared at 30 ℃. For T. chilonis, T. evanescens, T. ostriniae, T. dendrolimi and T. minutum, the RGB values of the body colors of female adults were significantly higher than those of males. 【Conclusion】Temperature can significantly affect the body color of adults of Trichogramma spp. The higher the rearing temperature, the lighter the body color of adults of Trichogramma.

Key words:  Trichogramma, temperature, body color, RGB, mesoscutum, scutellum