Wireworms are the subterranean larval stage of click beetles (Coleoptera: Elateridae). They are p... more Wireworms are the subterranean larval stage of click beetles (Coleoptera: Elateridae). They are pests of many agricultural crops including corn, sorghum, small grains, tobacco, and various vegetables, but are particularly damaging to potatoes, since the marketable portion of that crop is in the soil. Wireworms are found throughout the world, and species vary greatly across regions. In Virginia, three important pest species of agricultural crops are the corn wireworm, Melanotus communis, the tobacco wireworm, Conoderus vespertinus, and a related species, C. lividus (Fig. 1). A field survey of more than 60 fields in eastern Virginia from 2002 to 2004 revealed that 80% of wireworms collected were the corn wireworm, M. communis. This is the primary soil pest attacking potatoes in Virginia.
DupontTm LumiviaTM is a novel corn seed treatment containing the active ingredient Chlorantranili... more DupontTm LumiviaTM is a novel corn seed treatment containing the active ingredient Chlorantraniliprole, an insecticide in the anthranilic diamide class. Greenhouse and field experiments including corn seed treated with LumiviaTM demonstrated effective seed and seedling protection against wireworms and seedcorn maggot attack in Virginia in 2014.
European corn borer (ECB), Ostrinia nubilalis (Hübner), is regarded as a significant pest in Nort... more European corn borer (ECB), Ostrinia nubilalis (Hübner), is regarded as a significant pest in North America. Larvae bore into stems, stalks, or the fruit of a wide range of agricultural crops. Published 29 January 2010.
Colorado potato beetle (CPB): Leptinotarsa decemlineata (Say) Potato leafhopper (PLH): Empoasca f... more Colorado potato beetle (CPB): Leptinotarsa decemlineata (Say) Potato leafhopper (PLH): Empoasca fabae (Harris) 'Superior' potatoes were planted on 10 Mar at the Virginia Tech ESAREC near Painter, VA. Seed-piece pesticide treatments were applied on 9 Mar using a specially-designed roller apparatus that spun a 10 gal (37.9 liters) steel milk can, which tumbled 15 lb (6.8 kg) of potato seed, while the chemicals were applied directly to the seed with a hand-pump spray bottle containing 50 ml solution. Seed pieces for treatments 1, 2, 5, 6, 7 and 10 were also treated with Maxim 4FS at 1.25 g (AI) per 100 kg of seed (except treatment 2 at 0.31 g) while treatments 8 and 9 received Tops MZ at 63.7 g (AI) per 100 kg of seed. Furrows were cut using a commercial potato planter without the coulters on so that treated seed-pieces could be hand-dropped 11 inches (30.5 cm) apart. Platinum 2SC, Clutch and Venom 70SG drench treatments were applied over the furrow using 2 watering cans containing 20 pt (9.5 liters) of water each on 10 Mar. Immediately after the treated seed or the treatments were applied over the top of seed-pieces, the seed was covered. Plots were 2 row wide and 20 ft (6.1 m) long with unplanted guard rows on each side. Rows were planted on a 3 ft row center (0.9 m) in a 6 tier field design with 8 ft (2.4 m) alleys between tiers and a 16 ft (4.9 m) center alley. Treatments were arranged in a RCB design with four replicates. All plots were maintained according to local standard practices. CPB small larvae (SL) and large larvae (LL) were counted on 10 random stems / plot at 76 and 81 days after planting and plots were visually assessed for % defoliation on 7 Jun. On 12 May, stand counts were taken. On 6 Jun, PLH nymphs and aphids were counted on 10 randomlypicked, fully expanded compound leaves / plot. On 9 Jun, ECB damaged plants were assessed on 10 randomly picked potato plants. Harvest and weighing of potato tubers was conducted on 11 Jul. All data were analyzed using ANOVA procedures.
Harlequin bug, Murgantia histrionica (Hahn) (Hemiptera: Pentatomidae), is a piercingsucking pest ... more Harlequin bug, Murgantia histrionica (Hahn) (Hemiptera: Pentatomidae), is a piercingsucking pest of cole crops, causing cosmetic damage in low populations, while heavy pest pressure can kill plants or entire Þelds. Field studies were conducted to evaluate a trap crop for control of harlequin bug in collard. Field-cage choice tests found that potential trap crop plant species, mustard (Brassica juncea ÔSouthern Giant CurledÕ), rapeseed (B. napus ÔAthenaÕ), rapini (B. rapa), and arugula (Eruca sativa) attracted more harlequin bugs than collard (B. oleracea ÔChampionÕ) and a nonbrassica control, bean (Phaseolus vulgaris ÔBroncoÕ). Mustard was the most consistently selected by harlequin bug over collard in choice tests, and was found to be an effective trap crop for reducing feeding injury on collard at two experimental sites. Augmentation of the mustard trap crop with a systemic, neonicotinoid insecticide provided no added control of harlequin bug for the 10 wk duration in the spring season. KEY WORDS harlequin bug, Murgantia histrionica, cole crop, trap crop, choice test
Experiments were conducted to evaluate the toxicity, feeding preference, repellency, and Þeld efÞ... more Experiments were conducted to evaluate the toxicity, feeding preference, repellency, and Þeld efÞcacy associated with the organic insecticides azadirachtin, pyrethrins, and spinosad against two stink bug species, Acrosternum hilare (Say) and Euschistus servus (Say) (Hemiptera: Pentatomidae). Laboratory toxicity bioassays were conducted using treated green bean pods. The conventional pyrethroid-cyhalothrin was included for comparison. A. hilare adults and nymphs were most susceptible to-cyhalothrin and to tank mixes of pyrethrins ϩ spinosad. E. servus adults were susceptible to-cyhalothrin, spinosad, and all tank mixes, whereas E. servus nymphs were susceptible to-cyhalothrin only. Feeding preference tests were conducted using insecticide-treated tomatoes and counting the number of feeding stylet sheaths on fruit after 24 h. All tomatoes treated with either azadirachtin, pyrethrins, or tank mixes resulted in fewer numbers of stylet sheaths than the untreated control, whereas treatment with spinosad alone did not. In Þlter paper repellency tests, both E. servus and A. hilare were repelled by pyrethrins and exhibited no response to azadirachtin. E. servus was attracted to spinosad in comparison with a water-treated control; however, A. hilare displayed no response. In Þeld efÞcacy trials, each of the organic insecticides reduced the number of stink bugs in soybean, Glycine max (L.) Merr., for up to 2 d after treatment; however, none of the insecticides reduced stink bug damage to fruit in tomatoes even after multiple applications. Implications for organic growers and integrated pest management programs are discussed.
Chlorantraniliprole (=Rynaxypyr) is a novel anthranilic diamide insecticide that is of interest t... more Chlorantraniliprole (=Rynaxypyr) is a novel anthranilic diamide insecticide that is of interest to vegetable growers because of its low mammalian toxicity and systemic properties. Field trials were conducted between 2006 and 2008 in North Carolina and Virginia to test the efficacy of chlorantraniliprole as a drip chemigation treatment on tomatoes. Drip chemigation of chlorantraniliprole at various rates and intervals significantly reduced the percentage of tomatoes damaged by tomato fruitworm (Helicoverpa zea) comparable to that typically achieved from multiple foliar applications of insecticides. The best control was achieved with two applications of chlorantraniliprole at 0.074 kg ai/ha, or a single application at 0.099 kg ai/ha. Residual ingestion bioassays showed that chlorantraniliprole was effectively taken up by the roots and was active in leaves up to 66 days after treatment (DAT), active in blossoms up to 22 DAT, but was not active in fruit. Drip chemigation of chlorantraniliprole may offer several advantages over foliar applications, including ease of application, reduced pesticide input into the environment, reduced worker exposure to pesticides, and reduced risk to beneficial arthropods.
Wireworms are the subterranean larval stage of click beetles (Coleoptera: Elateridae). They are p... more Wireworms are the subterranean larval stage of click beetles (Coleoptera: Elateridae). They are pests of many agricultural crops including corn, sorghum, small grains, tobacco, and various vegetables, but are particularly damaging to potatoes, since the marketable portion of that crop is in the soil. Wireworms are found throughout the world, and species vary greatly across regions. In Virginia, three important pest species of agricultural crops are the corn wireworm, Melanotus communis, the tobacco wireworm, Conoderus vespertinus, and a related species, C. lividus (Fig. 1). A field survey of more than 60 fields in eastern Virginia from 2002 to 2004 revealed that 80% of wireworms collected were the corn wireworm, M. communis. This is the primary soil pest attacking potatoes in Virginia.
DupontTm LumiviaTM is a novel corn seed treatment containing the active ingredient Chlorantranili... more DupontTm LumiviaTM is a novel corn seed treatment containing the active ingredient Chlorantraniliprole, an insecticide in the anthranilic diamide class. Greenhouse and field experiments including corn seed treated with LumiviaTM demonstrated effective seed and seedling protection against wireworms and seedcorn maggot attack in Virginia in 2014.
European corn borer (ECB), Ostrinia nubilalis (Hübner), is regarded as a significant pest in Nort... more European corn borer (ECB), Ostrinia nubilalis (Hübner), is regarded as a significant pest in North America. Larvae bore into stems, stalks, or the fruit of a wide range of agricultural crops. Published 29 January 2010.
Colorado potato beetle (CPB): Leptinotarsa decemlineata (Say) Potato leafhopper (PLH): Empoasca f... more Colorado potato beetle (CPB): Leptinotarsa decemlineata (Say) Potato leafhopper (PLH): Empoasca fabae (Harris) 'Superior' potatoes were planted on 10 Mar at the Virginia Tech ESAREC near Painter, VA. Seed-piece pesticide treatments were applied on 9 Mar using a specially-designed roller apparatus that spun a 10 gal (37.9 liters) steel milk can, which tumbled 15 lb (6.8 kg) of potato seed, while the chemicals were applied directly to the seed with a hand-pump spray bottle containing 50 ml solution. Seed pieces for treatments 1, 2, 5, 6, 7 and 10 were also treated with Maxim 4FS at 1.25 g (AI) per 100 kg of seed (except treatment 2 at 0.31 g) while treatments 8 and 9 received Tops MZ at 63.7 g (AI) per 100 kg of seed. Furrows were cut using a commercial potato planter without the coulters on so that treated seed-pieces could be hand-dropped 11 inches (30.5 cm) apart. Platinum 2SC, Clutch and Venom 70SG drench treatments were applied over the furrow using 2 watering cans containing 20 pt (9.5 liters) of water each on 10 Mar. Immediately after the treated seed or the treatments were applied over the top of seed-pieces, the seed was covered. Plots were 2 row wide and 20 ft (6.1 m) long with unplanted guard rows on each side. Rows were planted on a 3 ft row center (0.9 m) in a 6 tier field design with 8 ft (2.4 m) alleys between tiers and a 16 ft (4.9 m) center alley. Treatments were arranged in a RCB design with four replicates. All plots were maintained according to local standard practices. CPB small larvae (SL) and large larvae (LL) were counted on 10 random stems / plot at 76 and 81 days after planting and plots were visually assessed for % defoliation on 7 Jun. On 12 May, stand counts were taken. On 6 Jun, PLH nymphs and aphids were counted on 10 randomlypicked, fully expanded compound leaves / plot. On 9 Jun, ECB damaged plants were assessed on 10 randomly picked potato plants. Harvest and weighing of potato tubers was conducted on 11 Jul. All data were analyzed using ANOVA procedures.
Harlequin bug, Murgantia histrionica (Hahn) (Hemiptera: Pentatomidae), is a piercingsucking pest ... more Harlequin bug, Murgantia histrionica (Hahn) (Hemiptera: Pentatomidae), is a piercingsucking pest of cole crops, causing cosmetic damage in low populations, while heavy pest pressure can kill plants or entire Þelds. Field studies were conducted to evaluate a trap crop for control of harlequin bug in collard. Field-cage choice tests found that potential trap crop plant species, mustard (Brassica juncea ÔSouthern Giant CurledÕ), rapeseed (B. napus ÔAthenaÕ), rapini (B. rapa), and arugula (Eruca sativa) attracted more harlequin bugs than collard (B. oleracea ÔChampionÕ) and a nonbrassica control, bean (Phaseolus vulgaris ÔBroncoÕ). Mustard was the most consistently selected by harlequin bug over collard in choice tests, and was found to be an effective trap crop for reducing feeding injury on collard at two experimental sites. Augmentation of the mustard trap crop with a systemic, neonicotinoid insecticide provided no added control of harlequin bug for the 10 wk duration in the spring season. KEY WORDS harlequin bug, Murgantia histrionica, cole crop, trap crop, choice test
Experiments were conducted to evaluate the toxicity, feeding preference, repellency, and Þeld efÞ... more Experiments were conducted to evaluate the toxicity, feeding preference, repellency, and Þeld efÞcacy associated with the organic insecticides azadirachtin, pyrethrins, and spinosad against two stink bug species, Acrosternum hilare (Say) and Euschistus servus (Say) (Hemiptera: Pentatomidae). Laboratory toxicity bioassays were conducted using treated green bean pods. The conventional pyrethroid-cyhalothrin was included for comparison. A. hilare adults and nymphs were most susceptible to-cyhalothrin and to tank mixes of pyrethrins ϩ spinosad. E. servus adults were susceptible to-cyhalothrin, spinosad, and all tank mixes, whereas E. servus nymphs were susceptible to-cyhalothrin only. Feeding preference tests were conducted using insecticide-treated tomatoes and counting the number of feeding stylet sheaths on fruit after 24 h. All tomatoes treated with either azadirachtin, pyrethrins, or tank mixes resulted in fewer numbers of stylet sheaths than the untreated control, whereas treatment with spinosad alone did not. In Þlter paper repellency tests, both E. servus and A. hilare were repelled by pyrethrins and exhibited no response to azadirachtin. E. servus was attracted to spinosad in comparison with a water-treated control; however, A. hilare displayed no response. In Þeld efÞcacy trials, each of the organic insecticides reduced the number of stink bugs in soybean, Glycine max (L.) Merr., for up to 2 d after treatment; however, none of the insecticides reduced stink bug damage to fruit in tomatoes even after multiple applications. Implications for organic growers and integrated pest management programs are discussed.
Chlorantraniliprole (=Rynaxypyr) is a novel anthranilic diamide insecticide that is of interest t... more Chlorantraniliprole (=Rynaxypyr) is a novel anthranilic diamide insecticide that is of interest to vegetable growers because of its low mammalian toxicity and systemic properties. Field trials were conducted between 2006 and 2008 in North Carolina and Virginia to test the efficacy of chlorantraniliprole as a drip chemigation treatment on tomatoes. Drip chemigation of chlorantraniliprole at various rates and intervals significantly reduced the percentage of tomatoes damaged by tomato fruitworm (Helicoverpa zea) comparable to that typically achieved from multiple foliar applications of insecticides. The best control was achieved with two applications of chlorantraniliprole at 0.074 kg ai/ha, or a single application at 0.099 kg ai/ha. Residual ingestion bioassays showed that chlorantraniliprole was effectively taken up by the roots and was active in leaves up to 66 days after treatment (DAT), active in blossoms up to 22 DAT, but was not active in fruit. Drip chemigation of chlorantraniliprole may offer several advantages over foliar applications, including ease of application, reduced pesticide input into the environment, reduced worker exposure to pesticides, and reduced risk to beneficial arthropods.
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