ObjectiveTetranychus cinnabarinus (Boisduval) is an agricultural mite pest threatens crops throughout the world, causing serious economic loses. Exploring the effects of acaricides on predatory mites is crucial for the combination of biological and chemical control of T. cinnabarinus. Neoseiulus californicus (McGregor) is one of the principal natural enemies of T. cinnabarinus, which can be applied in protected agriculture. In this study, the effects of sublethal concentrations of a new acaricide, SYP-9625 on two mite species, and the effects of the application concentration on predatory mite, N. californicus were assessed. The aim of the present study was to evaluate the effect of SYP-9625 on life parameters and predation capacity of N. californicus based on the concentration-response bioassay of T. cinnabarinus to explor the application of the new acaricide with natural enemy N. californicus.MethodAll of the experiments were conducted under laboratory conditions [25 ± 1°C, 16: 8 h (L: D) and 75 ± 5% RH]. The sublethal concentrations LC10 (0.375μg/mL) and the LC30 (0.841μg/mL) against T. cinnabarinus and the application concentration (100μg/mL) against N. californicus were used to evaluate the effects of SYP-9625 on population parameters of N. californicus based on an age-stage, two-sex life table and its predation capacity by functional response.Resultcinnabarinus females treated with LC30 exhibited significantly reduced net reproductive rates (R0 = 11.02) in their offspring compared with females treated with LC10 (R0 = 14.96) and untreated females (R0 = 32.74). However, the intrinsic rate of increase (rm) and the finite rate of increase (λ) of N. californicus indicated that the application concentration of SYP-9625 had no significant negative effect on N. californicus eggs (rm = 0.277, λ = 1.319) compared to the control (rm = 0.292, λ = 1.338). Additionally, most population parameters of N. californicus showed a dose-dependent manner with the increase of the concentration of SYP-9625 against T. cinnabarinus. SYP-9625 also stimulated the control efficiency of N. californicus against immobile stages including eggs and larvae.ConclusionThis study demonstrated that sublethal concentrations of SYP-9625 can inhibit the population growth of T. cinnabarinus. In addition, the sublethal concentrations and the application concentration showed no effect on the population growth of N. californicus. These two advantages described above showed great commercial potential of this new acaricide based on population parameters of the two mite species and predation capacity of the predatory mite under laboratory conditions.

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The development of granite reservoirs with high dip fractures has many difficulties, such as a high decline rate, early water breakthrough, and numerous economic losses. Gas injection is usually used to maintain the formation pressure to increase single well productivity, and could be carried out in fractured reservoirs to enhance oil recovery. When injecting associated gas, it meets the environmental protection requirements of the local government to further eliminate the flare, implementing the concept of green and low-carbon development. In this study, both laboratory tests and reservoir simulation have been done to study the feasibility and the benefit of associated gas injection in the research target. For physical stimulation, it mainly includes experiments such as associated gas injection expansion, slim tube, long core displacement, and relative permeability. Through these experiments, the changes in the recovery factor after depletion development and gas displacement are systematically described and the key controls are revealed for improving the recovery ratio of fractured basement reservoirs. For the simulation part, the embedded discrete fracture model processor combining commercial reservoir simulators is fully integrated into the research. A 3D model with complex natural fractures is built to perform the associated gas injection performance of the fractured granite reservoir. Complex dynamic behaviors of natural fractures can be captured, which can maintain the accuracy of DFNs and keep the efficiency offered by structured gridding. Depletion development and gas injection development strategy are optimized in this research. The result shows that oil recovery by using gas injection is increased by 16.8% compared with depletion development by natural energy.

11 Objective 12Exploring the effects of acaricides on predatory mites is crucial for the combination of