Onion Maggot Control Research Articles

Entomopathogenic Nematodes for Field Control of Onion Maggot (Delia antiqua) and Compatibility with Seed Treatments.

Onion maggot (Delia antiqua) is a prominent pest of allium crops in temperate zones worldwide. Management of this pest relies on prophylactic insecticide applications at planting that target the first generation. Because effective options are limited, growers are interested in novel tactics such as deployment of entomopathogenic nematodes. We surveyed muck soils where onions are typically grown to determine if entomopathogenic nematode species were present, and then evaluated the compatibility of entomopathogenic nematode species with the insecticides commonly used to manage D. antiqua. We also evaluated the efficacy of these entomopathogenic nematodes for reducing D. antiqua infestations in the field. No endemic entomopathogenic nematodes were detected in surveys of muck fields in New York. Compatibility assays indicated that, although insecticides such as spinosad and, to some extent, cyromazine did cause mortality of entomopathogenic nematodes, these insecticides did not affect infectivity of the entomopathogenic nematodes. Field trials indicated that applications of entomopathogenic nematodes can reduce the percentage of onion plants killed by D. antiqua from 6% to 30%. Entomopathogenic nematodes reduced D. antiqua damage and increased end of season yield over two field seasons. Applications of entomopathogenic nematodes may be a viable option for reducing D. antiqua populations in conventional and organic systems. Together with other management tactics, like insecticide seed treatments, applications of entomopathogenic nematodes can provide a yield boost and a commercially acceptable level of D. antiqua control.

Onion maggot control using novel seed treatments in onion, 2022

Onion maggot control using novel seed treatments in onion, 2022

Onion maggot control using seed treatments in New York onion fields, 2022

Onion maggot control using seed treatments in New York onion fields, 2022

Evaluating Foliar Insecticide Applications and Seed Treatments for Onion Maggot Control in Onion, 2022

Evaluating Foliar Insecticide Applications and Seed Treatments for Onion Maggot Control in Onion, 2022

Onion Maggot Control Using Seed Treatments in Onion, 2021

Onion Maggot Control Using Seed Treatments in Onion, 2021

Entomopathogenic Nematodes for Field Control of Onion Maggot (Delia Antiqua) and Compatibility with Seed Treatments

Entomopathogenic Nematodes for Field Control of Onion Maggot (Delia Antiqua) and Compatibility with Seed Treatments

Performance of novel insecticide seed treatments for managing onion maggot (Diptera: Anthomyiidae) in onion fields

Management of onion maggot, Delia antiqua (Meigen), in onion requires the use of an insecticide applied at planting. Insecticide resistance and a dearth of available products have stimulated an effort to identify new insecticides for onion maggot control, especially chemistries that can be delivered as seed treatments. Onion seeds film-coated with fipronil, spinosad, clothianidin or thiamethoxam were evaluated for onion maggot control in muck soils located in two major onion-growing regions in New York, USA in 2001–2003. Fipronil, spinosad and clothianidin at rates of 25, 25 and 50 g (a.i.)/kg of seed, respectively, consistently provided excellent control of onion maggot (⩽5% seedling loss). Moreover, these seed treatments performed well during wet and dry seasons. In contrast, thiamethoxam at a rate of 50 g (a.i.)/kg of seed failed to control onion maggot in three of the five experiments. Cyromazine seed treatment, which is currently used by onion growers, provided an equivalent level of onion maggot control to fipronil, spinosad and clothianidin. The other commonly used treatment, chlorpyrifos in-furrow drench, performed poorly in three of the four experiments, resulting in an average seedling loss of 17%. Insecticide resistance was implicated as the reason for the failure in two of the trials where seedling loss averaged 24%. Seed treatments provide growers with a convenient, reliable and environmentally responsible method for managing economically damaging onion maggot infestations, including those that are resistant to chlorpyrifos. Fipronil, spinosad and clothianidin seed treatments should be considered for future registration on onion. Availability of these chemistries would allow rotation with the cyromazine seed treatment, which would likely prolong the longevity of all products.

Insecticide and Fungicide Combinations to Optimize Control of Onion Maggot (Delia antiqua) and Onion Smut (Urocystis cepulae) in Ontario

ABSTRACT Changes in pesticide availability require that new compounds be tested for their efficacy in control of pests and pathogens on important vegetable crops. A study was conducted to determine the effectiveness of combinations of the insecticides LORSBAN® 15G (chlorpyrifos), GOVERNOR® 75WP (cyromazine), AZTEC® 2/0.1G (phosetbupirin + cyfluthrin) and REGENT® 80WG (fipronil), and the fungicides PRO-GRO® 30/50D (carbathiin + thiram), DITHANE DG® 75G (mancozeb), and PRO-GRO + DITHANE DG for control of onion maggot (Delia antiqua) and onion smut (Urocystis cepulae) in onions grown on muck soils in Ontario. Seed and granular in-furrow treatments were tested. Insecticide and fungicide efficacy varied depending on the pesticide combination. Effective control of both onion maggot (91–98%) and onion smut (57–100%) was achieved with insecticide treatments in combination with PRO-GRO + DITHANE DG. GOVERNOR and REGENT seed treatments provided the best onion maggot control. The best onion smut control was achieved...

Cyromazine seed treatments to control onion maggot, Delia antiqua, on green onions.

Cyromazine seed treatments were evaluated for onion maggot control in green onion crops. The more tolerant to organophosphates of two populations of onion maggots was chosen for further research, based on the results of adult assays in a Potter spray tower. In the laboratory, first-instar mortality was compared between film-coated seed treatment and soil drench treatment. The LC50 for the film-coated seed treatment was approximately one fourth that of the soil drench treatment. In choice assays, no significant difference was observed between the number of eggs deposited on seedlings grown from film-coated seeds with cyromazine and film-coated seeds without cyromazine. Field studies demonstrated that all rates of cyromazine seed treatment resulted in protection of onion plants from onion maggot damage. Green onions may not require as high a rate of cyromazine for control of onion maggots as the rate established for use in dry onions for two reasons: the seeding rate is much higher for green onions resulting in more AI/ha for a given amount of AI/kg of seed, and a given percentage of stand loss is more difficult to detect in green onions than in dry onions.

Interaction between cyromazine and the entomopathogenic nematode Heterorhabditis bacteriophora Poinar “GPS11” for control of onion maggot, Delia antiqua (Meigen)

Cyromazine seed treatments, which affect insect cuticle formation, and entomopathogenic nematodes, which must pass through openings in the insect cuticle, were applied independently and in combination to test for synergism between the two in their effects on onion maggots. In preliminary assays with Heterorhabditis bacteriophora, rates of 10–160 nematodes per larva caused significant mortality in both first and second stadium onion maggots. Cyromazine treatments, applied as a film-coated seed treatment at rates ranging from 0.78 to 50 g ai/kg seed, were tested alone and in combination with 5 and 10 nematodes per larva for first and second instars, respectively, to examine interactions between the insecticide and biological control. No significant interactions between cyromazine and nematode treatments were observed. Differences among rates of cyromazine in plant and larval mortality, however, were statistically significant, and differed for the two larval stadia examined. Although cyromazine and entomopathogenic nematodes could be used independently for onion maggot control without negative interactions, no synergistic effects should be expected from their combined use.

Integrated Management of the Onion Maggot (Diptera: Anthomyiidae)

In the absence of crop rotation, onion maggot, Delia antiqua (Meigen), control was inadequate (<10% plant loss) in field trials within a commercial onion production area when susceptible and potentially resistant onion genotypes were treated with chlorpyrifos at planting. However, when treatments were applied to the same entries in an area that had been rotated completely out of onion production the previous year, exceptional onion maggot damage reduction was noted (<2% plant losses). In the nonrotated area, one genotype (PI 432715) had reduced onion maggot damage compared with that of susceptible onion cultivars when treated with half rates of chlorpyrifos. Rotation of complete production areas can provide effective onion maggot control. When rotation is not possible, integration of plant resistance and judicious application of insecticides may be appropriate.

Onion Maggot Control with Seed Treatments, 1994

Abstract Seeds were planted 27 Apr in muck soil near Prattsburg, New York, on Franjo Farms. Plots were single rows, 30 ft long replicated 4 times in a randomized complete block design. Germination and damage counts were recorded from the center 20 ft of each row. All seeds were planted using a hand-pushed cone seeder at the rate of 9 seeds/ft. All seeds were treated with Progro at the rate of 25 g of formulation/kg of raw seed to minimize incidence of onion smut (Urocystis cepulae). The standard in-furrow treatment of Lorsban and one check, were treated with Dithane F-45, rather than Progro, applied in-furrow at 2.4 qts formulation in 75 gal water/acre based on a 15-inch row width.

Onion Maggot Control with Seed Furrow Treatments, 1994

Abstract Seeds were planted 27 Jun, excepting the Stalker treatment planted 9 May, in muck soil near Prattsburg, New York, on Franjo Farms. Plots were single rows, 30 ft long replicated 4 times in a randomized complete block design. Germination and damage counts were recorded from the center 20 ft of each row. All seeds were planted using a hand-pushed cone seeder at the rate of 9 seeds/ft delivering 75 gal of water/acre. In-furrow insecticide treatments were based on a 15 inch row width with Dithane F-45 applied in the furrow at 2 qts formulation/acre to minimize onion smut (Urocystis cepulae). Final stand counts were made on 1 Jun with the exception of the Stalker treatment where final counts were made 6 Jun. Damage readings were made from 3 Jun through 7 Jul.

Ovipositional Patterns and Larval Movement of Delia antiqua (Diptera: Anthomyiidae) on Sprouted Bulb and Seedling Onions

Delia antique (Meigen) exhibited pronounced differential oviposition on seedling versus sprouted bulb onions. In a dual treatment experiment, /lies laid significantly more eggs per plant per day on sprouted bulbs (97.4 ± 14.4 [mean ± SEM]) than on seedlings (0.4 ± 0.3). In a single-treatment experiment, sprouted bulbs received 103.2 ± 11.4 eggs per plant/d and seedlings only 3.5 ± 1.8. Switching treatments in the single treatment experiment caused an immediate reversal in oviposition. Flies first given sprouted bulbs ceased oviposition when presented with seedlings and Flies switched from seedlings to sprouted bulbs commenced oviposition. Therefore, once activated, the fixed action pattern governing D. antique egg deposition is not free-running. In glasshouse experiments, sprouted bulbs did not influence the pattern of egg deposition by female Flies on surrounding seedlings, indicating that ovipositional patterns cannot fully explain aggregated damage observed in the field. Onion maggot movement away from sprouted bulbs previously inoculated with high numbers of eggs resulted in aggregated damage to surrounding seedlings, at least partially explaining field observations. Differential oviposition supports the use of sprouted bulbs as an ovipositional trap crop for onion maggot control, but larval movement away from potentially impenetrable, undamaged bulbs requires consideration of trap crop placement relative to seedlings, timing of planting so that the seedling stage coincides with peak D. antique oviposition, and timing of, trap crop removal.

Onion Maggot Control with Trigard Seed Treatments, 1992

Abstract Two experiments were planted 4 May in muck soil near Prattsburg, New York, on Franjo Farms. Treatments were single rows, 30 ft long, replicated 4 times in a randomized complete block design. Germination and damage data were recorded from the center 20 ft of each row. All treated seeds were sown and seed-furrow treatments of insecticides were applied using a hand-pushed cone seeder that planted 9 seeds/ft and delivered 75 gal of water/acre through a gravity-fed system based on a 15 inch row width. Trigard 75 WP was applied to the seed either by pelleting or film coating. Pelleted treatments were applied by mixing Trigard 75 WP with 140 mesh sand and coating it using a copper pan treater and air brush. Progrow (Vitavax and Thiram) was included in the pellet for each specified seed treatment at the rate of 25 g of formulation/kg of seed and Dithane (F45) applied in the furrow with the Lorsban drenches at 2.4 qts formulation/acre for control of onion smut, Urocystis cepulae. Film treatments were applied by suspending Trigard 75 WP in a 15% soln of Opadry F (Colorcon Co.) and then spraying the seeds. Progrow was applied during the film-coating procedure.

Onion Maggot Control with Seed Furrow Treatments, 1992

Abstract Seeds were planted 4 May in muck soil near Prattsburg, New York, on Franjo Farms. Plots were single rows, 30 ft long, replicated 4 times in a randomized complete block design. Germination and damage data were recorded from the center 20 ft of each row. All seeds were sown and treatments of insecticides were applied in the seed furrow using a hand-pushed cone seeder that planted 9 seeds/ft and delivered 75 gal of water/acre through a gravity-fed system. Insecticide treatments were based on a 15 inch row width. Dithane F-45 was applied in the furrow with each treatment at 2.4 qts formulation/acre for control of onion smut, Urocystis cepulae. Stand counts were taken 28 May. Maggot damage was assessed by checking each row for wilted plants ca. twice/wk from the time of stand counts until 20 Jul.

Onion Maggot Control Using Pelleted Seed Treatments, 1990

Abstract The plot was planted 27 Apr in muck soil near Prattsburg, N.Y. on Franjo Farms. Plots were single rows, 30 ft long, replicated 4 times in a randomized block design. Germination and damage data were recorded from the center 20 ft of each row. All seeds were sown and seed-furrow treatments of insecticides were applied using a hand-pushed cone seeder which planted 9 seeds/ft and delivered 75 gal/acre through a gravity-fed system. Trigard 75 WP was applied to the seed by mixing it with 140 mesh sand and pelleting it using a copper pan treater and air brush. Progrow (Vitavax and Thiram) was included in the coating of each treatment at the rate of 25 g of formulation/kg of seed for control of onion smut (Urocystis cepulae).

Stimulo-deterrent diversion: A concept and its possible application to onion maggot control

Considerable basic information has been gathered on the interaction between the onion fly (Delia antiqua) and its host plant, the onion (Allium cepa). An attempt is underway to manipulate ovipositional behavior of this pest by treating onion seedlings with chemical deterrents while simultaneously providing deeply planted onion culls on which onion flies prefer to lay. This bipolar strategy of behavioral manipulation, termed "stimulo-deterrent diversion" (SDD), has the advantages of: (1) avoiding severe pest deprival and concomitant overriding of deterrents, (2) combining the effects of "push" and "pull" multiplicatively, and (3) providing opportunities for enhanced biological control in sites where the pest becomes concentrated. The suggestion is made that using SDD along with soil insecticide might relax or even reverse selection for physiological resistance ofD. antiqua to insecticides. As tools of molecular biology open new possibilities for manipulating plants and their allelochemicals, applied chemical ecologists should consider arranging situations where the allelochemicals have clear and adaptive messages for the pest. By combining toxins and deterrents at sites where feeding should be prevented, while simultaneously expediting use of alternative plants or plant parts, it might be possible to guide pest evolution toward paths of less conflict with human interest.

Pungent spices, ground red pepper, and synthetic capsaicin as onion fly ovipositional deterrents

In laboratory choice experiments, the spices dill, paprika, black pepper, chili powder, ginger, and red pepper deterredDelia antiqua oviposition by 88-100%. Dose-response choice tests demonstrated that 1 mg of ground cayenne pepper (GCP) placed within 1 cm of artificial onion foliage reduced oviposition by 78%. A synthetic analog of capsaicin, the principal flavor ingredient of red peppers, deterred oviposition by 95% when present at 320 ppm in the top centimeter of sand (the ovipositional substrate). However, in no-choice conditions 10 mg GCP was not an effective deterrent. Sevana Bird Repellent and Agrigard Insect Repellent both use red pepper as a principal ingredient; at recommended field rates, neither of these materials was an effective ovipositional deterrent either in laboratory or field. Capsaicin-based materials do not appear to be candidates for onion maggot control via behavioral modification.

Control of Onion Maggot, 1987

Abstract Two separate trials for onion maggot control were carried out in 1987 at 2 locations. The first trial was designed to evaluate tolerance of a local onion maggot population to Lorsban and was carried out near Grant, Mich. The second trial was carried out near Orangeville, Mich., with the objective of testing new compounds and application strategies against labeled standards.