| Choice of different host plants, development times ,life table parameters and biomechanism of D. antiqua (Meigen) were determined on four host plants:onion,scallion,garlic and leek.In addition, toxicity of some insecticides and activity of hexaflumuron and cyromazine on D. antiqua larvae were studiedThe results are as follows:1. The test in the laboratory and in the fields showed:The trend of oviposition choice ofD. antiqua was the same, the choice ratio was the highest on onion, followed by garlic, scallion and leek, Which was possibly related to ingredient and content of sulphur-bearing chemicals in four host plants by analysis.2. The trend of the feeding choice of D. antiqua 1st and 3rd instar larvae were the same,which was the highest on onion,followed by leek,scallion and garlic.The choice ratio of 3th instar larvae on onion was 61%,that was more than 38% which of 1th instar on onion.3. On all host plants, significant relationships were founded between larval survival, duration of larval stage, pupal weight, adult eclosion rate and fecundity. The highest larval survival was recorded in D. antiqua reared on onion (82.2%), followed by scallion (78.99%), garlic (77.8) and leek (62.1); duration of the larval stage was the shortest on scallion (15.18 d) and longest on leek (16.60 d); adult eclosion rate was the highest on onion (100%) and the lowest on garlic (82.15%); the highest number of female progeny was recorded on onion, followed by scallion, garlic and leek. The relationships between egg hatchability, pupal duration, egg prophase and adult longevity on different host plants were not significant.4. Special age life table of D. antiqua were bulided on four host plants. Four key statistics were used to assess performance of D. antiqua. Using these measures, D. antiqua performance was best on onion, worst on leek, and intermediate on scallion and garlic.5. The test showed: the effect of different host plants on D. antiqua respiration wasn't evident, the highest respiration was on onion and the lowest was on leek, thatshowed D. antiqua feeding on onion was strong vital. However, significant relationships weren't founded between supercooling point and cooling point of D. antiqua.6. In all host plants, significant relationships weren't founded between soluble suger content, dissociative ammo acid content, protein content and nitrogen content. The highest soluble suger content was on leek (2.1025mg/g) and the lowest was of garlic (0.8787mg/g); the highest nitrogen content was of garlic (2.52%) and lowest was of scallion (1.71%). Synthetic analysis: the mainly factors affected development of D. antiqua wasn't nutritional ingredient of host plants.7. Biochemical results showed: rearing for up to three generations on either host plants, the activity of carboxylesterase (CarE) was significant correlated to host plants, the highest was on garlic (0.58mmol.L"1.mgPr"1.15min"1),followed by onion, leek and scallion. That showed detoxifcative energy was enhanced by larvae feeding on different host plants. Relationship between acetylcholinesterase (AchE) was a little significant, the highest is on onion (0.07415 mmol.L"1.mgPr"1.15min"1) and the lowest was on leek, which showed onion was fit for D. antiqua.8. A laboratory bioassay showed: chlorpyrifos, phoxim, triazophos could control D. antiqua 1st instar well and they were not seriously phytotoxic in any of the trials,LCso (ppm) were 0.3932,0.5637 and 0.6860,respectively.Above-mentioned insecticides were much effective to 3th mstar,LC50 (ppm) were 2.5284,7.0940 and 8.5924.The toxicity and activity of the insect growth regulator, cyromazine and hexaflumuron, to D. antiqua larvae were higher. The effective insecticides to D. antiqua in pot test were diazinon, chlorpyrifos and phoxim.9. Significant mortality of 1st larvae due to cyromazine and hexaflumuron were observed , compared to routine insecticides, and resulted 3rd instar in abnormality, because they have different mode of action than the current insecticides. Cyromazine and hexaflumuron...
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