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Many studies have demonstrated that many species of parasitoid wasps can control offspring sex ratio in response to environmental variables. This article tests the effects of temperature, relative humidity, photoperiod, foundress number, foundress age, host number, interval time of host supplying, species of food, species of host and symbiotic bacterium (Wolbachia) on sex ratio of Trichogramma ostriniae. Results showed that the sex ratio of T. ostriniae was affected significantly by temperature (35°C), number of foundress (>2 number), age of foundress (3-day-old) and Wolbachia. Through transmitted Wolbachia from Trichogramma embryophagum to Trichogramma dendrolimi, even the reproductive mode of T. dendrolimi was changed from gamogenesis to thelytoky. Our work verifies the sex ratio theory and implies that the potential effectiveness of Trichogramma spp. as a biological control agent can be further improved.

Supplementary cementitious material (SCM) plays an important role in blended cement, and the effect of the particle size and morphology of siliceous supplementary cementitious material on hydration should not be ignored. In this study, 0.5 h and 1 h of wet grinding was applied to pretreat iron ore tailing powder (TP), and the divergence in pozzolanic behavior and morphology were investigated. Then, the treated TPs were used to replace the 30% cement contents in preparing blended cementitious paste, and the impact mechanism of morphology on performance was studied emphatically. M, the autogenous shrinkages of pastes were tested. Finally, hydration reaction kinetics was carried out to explore the hydration behavior, while X-ray diffraction (XRD) and thermogravimetric analysis (TGA) were used to characterize the hydration product properties, respectively. Meanwhile, microscopy intrusion porosimetry (MIP) was also carried out to characterize the pore structures of hardened specimens. Results indicated that wet grinding has a dramatic effect on particle size and morphology, but hardly affects the phase assemblages and pozzolanic reactivity of TP, while the particle shape of TP changes from sub-circular to clavate and, finally, back to sub-circular. The results of hydration reaction kinetics, representing the morphology of particles, had a significant effect on hydration rate and total heat, and compared with the sub-circle one, the clavated particle could inhibit the hydration procedure. With the increasing grinding time, the compressive strength of cementitious paste was increased from 17.37% to 55.73%, and the micro-pore structure became denser; however, the autogenous shrinkage increased.