Effects of gyrase inhibitors on the total protein content of Pimpla turionellae L. reared on an artificial diet

The effects of antibiotics, novobiocin, nalidixic acid and oxolinic acid, singly and in combinations, on the wet weight and total protein content of the hymenopterous endoparasitoid, Pimpla turionellae L., were investigated by rearing the larvae aseptically on chemically defined synthetic diets. Oxolinic acid, at all levels tested, caused a greater increase in the total protein content of the young pupae than other antibiotics; whereas, 2.25 mg of this agent decreased both the wet weight and total protein of adults. However, this antibiotic did not affect the pupal wet weight. High levels of novobiocin increased the protein content of the pupae but had no effect on that of the adults. The lowest level of this antibiotic significantly increased pupal and adult wet weight. While this level of antibiotic had no effect on pupal protein content, it significantly increased the protein content of adults. The highest tested level of nalidixic acid caused a significant decrease in the pupal and adult wet weight of the insect. This level increased total protein content of the pupae. None of the tested levels of this antibiotic had an effect on the protein content of the adults. The combinations with two antibiotics had no significant effects on the total protein content, while some increased the wet weight of the insect. Some ternary combinations of novobiocin, nalidixic acid and oxolinic acid (6.0:2.0:0.75, 6.0:2.0:3,0, and 1.5: 4.0:0.75 mg) significantly increased the total protein content in adults of the insect, and the combination of 6.0:2.0:0.75 increased the protein content and wet weight of pupae. It is suggested that these three antibiotics singly and in combination can be used in artificial rearing of this parasitoid.