Chain-ing, T. Shih, Chang. H.Y., Hsu, P.H. and Hwang, Y.F., 1993. Responses ofAmblyseius ovalis (Evans) (Acarina: Phytoseiidae) to natural food resources and two artificial diets. Exp. Appl. Acarol., 17: 503-519.Six phytophagous mites, maize pollen, and two artificial diets were fed to Amblyseius ovalis to evaluate their food suitability for the predator. The paraffim diet-chip of Hager and Tassan was adopted for artificial diet studies. The floating leaf method was the best among all tested methods, producing high survival, developmental, and reproductive rates of the predator. Offspring ofA. ovalis feeding on artificial diets did not complete their life cycles. A. ovalis feeding on E. orientalis, O. mangiferus, ad O. taiwanicus developed into adult form faster than those feeding on other tbod resources. Predators feeding on the natural food, except those feeding on T. kanzawai, had much higher immatural survival rates, lower escape rates, and shorter developmental durations than those feeding on the artificial dicts.All A. ovatis laid an average of two eggs per female per day after 2 days of prcoviposition, except for those feeding on 11 kanzawai which produced none. A. ovalis feeding on artificial diets showed a shorter oviposition period, lower daily and total reproductive rates, and shorter longevity. The complicated webbing life type of T. kanzawai inhibited the activities ofA. ovalis, indicating that the predators may require nutrients other than T. kanzawai eggs to molt into adults and to reproduce. The functions varying the phytoseiid-tetranychid relationship during the predator's approach to the microhabitat of the prey were postulated from the predator's structures and the prey's life type. Most predator eggs were laid by 2-18 day-old females feeding on natural food resources.A, ovatis retained its high activity on the low webbing habitats of O. mangiferus and E. orientalis, and on maize pollen. The intrinsic rate of increase, mean generation time, and net reproductive rate ofA. ovatis on each of nine tested food resources were evaluated from its life tables. The predator showed the highest intrinsic rates of increase when feeding on the prey of E. orientalis, O. nutngiferus, and on maize pollen, and the lowest rates when feeding on the artificial diet even when the immatures had ted on the O. mangiferus and maize pollen. Consequently, the optimal food resources for A. ovalis appear to be O. mangiferus or O. orientatis with supplements of maize pollen. When fed on these food resources, the predators demonstrated the highest rates of survival, longevity, fecundity, and intrinsic increase.

BACKGROUND Green lacewings (Neuroptera: Chrysopidae) are important beneficial insects that can be raised on artificial diets for culturing experimental lines. An encapsulation method for embedding a core material within a sealed shell to prevent evaporation and biological contamination is crucial for providing food to these predatory insects. RESULTS This study presents a new encapsulation process to mass produce a core–shell microcapsule diet for rearing Mallada basalis (Walker) (Neuroptera: Chrysopidae). This new process provided consistent quality control and effectiveness of the microcapsule diet (742.1 ± 11.3 μm in diameter and 44.2 ± 1.9 μm in shell thickness). Furthermore, significant differences were measured in larval development (24.0 ± 0.3 vs. 20.1 ± 0.6 days) and fecundity (465 ± 65.05 vs. 678 ± 54.91 eggs) on comparing the development of M. basalis larvae fed the old and new diets. Survival rates increased in both single‐ and group‐rearing tests for adults fed the new diet during the larval stages. Neither diet affected predation rates for M. basalis larvae preying on nymphs of Aphis gossypii Glover (Hemiptera: Aphididae) and Bemisia argentifolli Bellows and Perring (Hemiptera: Aleyrodidae). CONCLUSION Compared with the old process, the new encapsulation process requires reduced effort during preparation, and reduces the weight, cost and space occupied by the equipment. The results of this study suggest that this new spherical microcapsule artificial diet is suitable for group‐rearing of M. basalis and may be appropriate for mass‐rearing of other types of carnivorous insects. © 2019 Society of Chemical Industry