Fly, onion

What to do Grow plants under fleece or fine mesh netting, put in place immediately after sowing or planting. Remove infested plants as soon as onion fly is discovered. Rotate crops cultivate soil in winter to expose pupae to predators. 

Imidacloprid (1) provides additional control of Cokopteran spp. (e.g., rice water and tobacco weevil, Colorado potato beetle, rice leaf beetle, wrreworms, grubs and other soil beetles) and Dipterans spp. (e.g., fruit fly, beet fly, bean and onion fly) and of selected micro-lepidopteran species (e.g., citrus, apple and potato leaf miner), ants Hymenoptera spp.), termites Isoptera spp.), cockroaches, grasshoppers and crickets Orthoptera spp.) [53]. 

Fipronil s high intrinsic activity against Dipterans allows its successful use as a seed treatment in several crops for control of root maggots. In cereals, fipronil provides excellent control of wireworm and wheat bulb fly (Delia coarctata) at rates of 50 g per 100-kg seed [8]. In leeks, seeds filmDelia antiqua) as well as thrips and onion moth [106, 107]. 

Ishikawa, Y., IkeshojI, T. Matsumoto, Y. (1978) A propylthio moiety to the oviposition attractant and stimulant of the onion fly, Hyiemya antique Meigen. Appi. Entomoi. Zooi. 13, 115-122. 

Several species of insects are associated with Allium species. For example, both adults and larvae of Delia antiqua, the onion fly, are atb-acted to disulfides characteristic of these plants (Stadler, 1992). Another specialist, the leek moth, Acrolepiopsis assectella, was found to respond to the same group of compounds. However, dipropyl sulfinate, the precursor of the disulfides, is even more stimulatory. A parasite of the leek moth, Diadromus pulchellus (Ichneumoni-dae), reacts mainly to the disulfides that emanate from leaves damaged by the leek moth (Stadler, 1992). 

Dindonis, L. L. and Miller, J. R. (1980) Host-finding behavior of onion flies, Hylemya antiqua. Env. Ent., 9, 769-72. 

The onion fly, D. antiqm, exhibits oviposition behaviors similar toD. brassicae... 

Onions (and other albums) should not be grown more often than one year in fom, and ideally one year in six in the same field, because of the risk of nematode, onion fly and white rot disease. 

The following can affect bulb onions leaf blotch, downy mildew, onion white rot, neck rot, onion fly, cutworms, bean seed fly, thrips and bulb and stem nematode. 

Cutworms, bean seed fly, onion fly, leek moth and thrips can be a problem in the crop. Rust, foot rot, leaf blotch, white tip and white rot are the main disease problems in leeks. 

Figure 1. Scanning electron micrograph of an opened onion fly spermatheca revealing the orderly and dense packing of stored spermatozoa. The white bar in the upper right comer is 10 microns long.

We have examined onion fly paragonial extract by matrix-assisted laser desorption-ionization time-of-fli t (MALDI-TOF) mass spectrometry (70). Figure 4 A reveals the components in the molecular weight range suspected of containing onion fly sex peptide. We speculate that onion fly sex peptide will turn out to be a peak conunon to the onion fly and seedcom fly extract (Figure 4 B), since extracts of paragonia from these two very closely related species are cross-reactive (J. L. Spencer and J. R. Miller, unpublished), antitative analyses of behavioral effects of these sex peptides await better qualitative and quantitative definition of stimuli. 

Figure 3. Elution profile of onion fly paragonial gland extract upon microbore C18 RP-HPLC fractionation using a linear gradient of ethanol/isopropanol in phosphate buffered saline. Ovipositional-stimulating activity was associated only with Peaks 1 and 2.

Figure 4. Matrix-assisted laser-desorption/ionization time-of-flight (MALDI-TOF) mass spectra for onion fly (Delia antiqua) and seedcom fly (Delia platura) paragonial gland extracts. Sex peptides of other Diptera fall in the range of MW 3,000 - 5,000.

Weston, P.A. J.R. Miller. 1985. Influence of cage design on precision of tube-trap bioassay for attractants of the onion fly, Delia antiqua. J. Chem. Ecol. 11 435-440. 

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