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Spodoptera litura is widely used as a test in a research controlling pests in the laboratory so it needs to be maintained to get uniform test insects in large numbers. Rearing of insects in laboratory can use natural food or artificial diets. The purpose of this study was to know the number and percentage of deaths in each phase, the alleged cause of death in each phase, and know the passed of rearing S. litura in  laboratory using artificial diet. Rearing of insects is carried out in the Entomology laboratory, Faculty of Biology, Universitas Gadjah Mada. Artificial diet used is Poitout diet with modification. Data obtained from the results of rearing of S. liturain laboratory are then arranged in the form of life tables at the end of the phase, the alleged cause of death, and the percentage of deaths. The results showed the passed of rearing  in laboratory using artificial diet was 74.8%. Larvae death by15.7%, pupae that did not develop into imago by 11.3%, imago death by 4.7%, and eggs that did not passed is 18.2%. Alleged causes of death in all phases add to the contamination of diet by fungi, larvae eaten by other larvae, temperature and the capacity of the rearing chamber that are not compatible with the breeding of insects.

Spodoptera litura Fab. is an insect that damage cultivated plants in Indonesia. Efforts to control it can be done by using biological agents for example by using Bacillus thuringiensis kurstaki (Btk.). Unfortunately, the Btk. is easily degraded by UV radiation. This research aimed to study the effectiveness of red and green spinach as UVB protection for Btk. and to observe the pathogenicity of Btk. formulations against armyworm. Furthermore, the sublethal effect of Btk. against S. litura was investigated. The morphology of the endospore, protein crystal, and bacterium were observed under a contrast phase microscope. The extracts at 2% (w/v) were mixed with Btk. suspensions at 5 x 104, 5x105, and 5x106 (spores/ml), respectively. The formulations then exposed under Ultraviolet B (UVB) lights for 3, 6, and 9 hours then tested against the 3rd larval instar of armyworm. The larval mortality was observed daily and the analysis of variance was analyzed by one way anova. The sublethal effects of the treatment to the pupal and adult stages were observed when the moths emerge. The results showed that the larval mortality caused by  Btk. mixed with red spinach ranged from 11.7 to 26.7%. The sublethal effects of Btk. resulted in smaller sizes of pupae and imago, darker pupae, and wings abnormality of the adult stage, compared to any control treatment. The morphological observation of the bacteria showed that extracts gave UV protection against UVB. These results suggested that red and green spinach potentially can be used as a protectant for Btk. against UVB.

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The objective of this research was to evaluate artificial diets that can be used to successfully culture the atlas silk moth, Attacus atlas L. (Lepidoptera: Saturniidae) indoors. Four plant species were evaluated as the basic component of each diet, barringtonia (Barringtonia asiatica), cheesewood (Nauclea orientalis), soursop (Annona muricata), and mahogany (Swietenia mahagoni). Evaluation of the nutritional value of each diet was determined by an analysis of the hemolymph proteins of sixth instars using the Folin-Ciocalteu assay. Survivorship, cocoon quality, and hemolymph protein content of larvae fed the barringtonia diet were higher than those of larvae fed mahogany-, cheesewood-, and soursop-based artificial diets. The average adult emergence of those fed the barringtonia-based diet was 74.5%. The weights of the cocoon in this treatment with the pupa and the empty cocoons were 7.0 and 1.1 g, respectively. Hemolymph of the larvae fed the barringtonia-based artificial diet had the highest concentration of protein with an average of 28.06 mg/ml. The atlas moth reared on the barringtonia-based artificial diet was comparable with those reared only on barringtonia leaves. However, the weight of empty cocoons, adult wingspan, and amount of hemolymph protein were lower than in those reared on barringtonia leaves only. This may suggest that the artificial barringtonia-based diet requires additional protein for maximum efficiency.