Methanolic extract of Artemisia annua L. were evaluated on growth and nutritional efficiency of lesser mulberry pyralid Glyphodes pyloalis (Lepidoptera: Pyralidae) in laboratory conditions (24±1°C, 75±5% RH and 16 L : 8 D). Feeding deterrence index was evaluated by a choice test method on < 24 h fifth instar larvae with 5, 2.5, 1.25 and 0.625 percent of the extract. The result indicated that increasing the concentration resulted in higher deterrence. The extract retarded larval growth significantly (EC 50 = 3.63%) and also showed significant effects on the relative growth rate (RGR), efficiency of conversion of ingested food (ECI), efficiency of conversion of digested food (ECD), approximate digestibility (AD) and consumption index (CI). Lipid, protein and carbohydrate in treated insects were significantly reduced compared to the controls. Hence, methanol extract of A. annua could be considered as a strong deterrent which also affects the biochemical metabolism of the target pest. Methanol extract of A. annua has the potential for development as a botanical insecticide.

Synthetic organic compounds and those of plant origin used in insect pest control are known to affect digestive enzymes and biochemical compounds. The lesser mulberry pyralid Glyphodes pyloalis Walker is a monophagous and dangerous pest of mulberry that has been recently observed in Guilan province, northern Iran. In this study the effect of the neem formulation, Achook (0.03% azadirachtin) was studied on nutritional physiology and gut enzyme activity of the lesser mulberry pyralid G. pyloalis. The LC 25 , LC 50 , and LC 90 values on 4th instar larvae were estimated as 113.6, 256.84, and 1,210.02 ppm, respectively. The neem insecticide exhibited a significant antifeedant activity when used at the highest concentration. When G. pyloalis larvae were provided with mulberry leaves treated with the neem extract, all nutritional indices, except approximate digestibility, decreased. Neem was found to affect digestive enzyme activities in the midgut of treated larvae. When larvae were fed on treated leaves, biochemical compounds in the hemolymph, such as protein, lipid, and glucose decreased but the amount of uric acid increased compared with the control.

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The lesser mulberry pyralid, Glyphodes pyloalis Walker (Lepidoptera: Pyralidae) is a monophagous and dangerous pest of mulberry that has been recently observed in Guilan province, northern Iran. In this study, the crude methanol extract of sweet wormwood Artemisia annua L. (Asterales: Asteracaea) was investigated on toxicity, biological and physiological characteristics of this pest under controlled conditions (24 ± 1 °C, 75 ± 5% RH, and 16:8 L:D photoperiod). The effect of acute toxicity and sublethal doses on physiological characteristics was performed by topical application. The LC50 and LC20 values on fourth instar larvae were calculated as 0.33 and 0.22 gram leaf equivalent/ mL, respectively. The larval duration of fifth instar larvae in LC50 treatment was prolonged (5.8 ± 0.52 days) compared with the control group (4.26 ± 0.29 days). However larval duration was reduced in the LC20 treatment. The female adult longevity in the LC50 dose was the least (4.53 ± 0.3 days), while longevity among controls was the highest (9.2 ± 0.29 days). The mean fecundity of adults after larval treatment with LC50 was recorded as 105.6 ± 16.84 eggs/female, while the control was 392.74 ± 22.52 eggs/female. The percent hatchability was reduced in all treatments compared with the control. The effect of extract in 0.107, 0.053, 0.026 and 0.013 gle/mL on biochemical characteristics of this pest was also studied. The activity of α-amylase and protease 48 hours post—treatment was significantly reduced compared with the control. Similarly lipase, esterase, and glutathione S-transferase activity were significantly affected by A. annua extract.

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