several species of flea beetles ( Altica spp.) ( Byers, 1997 ; Egolf and Andrick, 1978 ; Mizell and Knox, 1993 ). In recent years, there have been numerous reports by nursery growers of sudden and severe damage to young crape myrtle plantings by the
Abstract
The trend towards total mechanization of the production of processing tomatoes is creating many new problems. This paper describes one which may become very important as the practice of direct seeding in the field partly replaces the use of transplants.
: Noctuidae), spanworms (Lepidoptera: Geometridae), fireworms (Lepidoptera: Tortricidae), and a flea beetle (Coleoptera: Chrysomelidae) ( Averill and Sylvia, 1998 ). Injury by these pests can be extensive with respect to loss of vegetative tissue ( Averill and
cropping and during the crop-growing season. For example, in the crop-growing season, spinetoram and cyantraniliprole are applied to control striped flea beetle, diamondback moth, and tobacco cutworm ( Spodoptera litura ) ( Hong et al., 2017 ; Li et al
the wireworm-cucumber beetle-flea beetle (WDS) severity index ( Chalfant et al., 1990 ). This complex of insect pests consists of several species of wireworms (e.g., Melanotus communis and Conoderus sp.), banded and spotted cucumber beetles
Abstract
Soil insect root injury to resistant sweet potato [Ipomoea batatas (L.) Lam.] cultivars ‘Regal’ and ‘Southern Delite’ was compared to injury to ‘Jewel’ and ‘Centennial’ in trials with the resistant-standard W-13 and the susceptible-standard SC 1149-19. Injury by three groups of insects was evaluated: the wirewoom-Diabrotica-Systena complex (WDS), which includes the southern potato wireworm (Conoderus falli Lane), the tobacco wireworm (C. vespertinus Fabricius), the banded cucumber beetle (Diabrotica balteata LeConte), the spotted cucumber beetle (D. undecimpunctata howardi Barber), the elongate flea beetle (Systena elongata Fabricius), the pale-striped flea beetle (S. blanda Melsheimer), and S. frontalis Fabricius (a flea beetle); the sweet potato flea beetle (Chaetocnema confinis Crotch.); and a white grub (Plectris aliena Chapin). Relative control estimates were obtained by comparison to the susceptible standard. ‘Regal’ and ‘Southern Delite’ provided good control of all three insect groups with control of all insect injuries of 79.2% and 81.0%, respectively. ‘Jewel’ and ‘Centennial’ were resistant to the sweet potato flea beetle and sustained less damage by WDS than the susceptible standard, but would still be classed as susceptible to WDS. ‘Centennial’ was as susceptible to the white grub as SC 1149-19. The levels of resistance demonstrated for ‘Regal’ and ‘Southern Delite’ would provide growers an alternative to insecticides for the control of these insects.
Abstract
Advances attained by the sixth generation of mass selection in sweet potato (Ipomoea batatas (L.) Lam.) were assessed. The objective was to combine multiple resistances to pathogens, nematodes and insects with other desirable production and market qualities. Although progress from 6 single-year cycles of selection was encouraging, a change to 2-year cycles was indicated. Generation 6 contained high frequencies of flowering and seed set, attractive root shape, orange flesh, thin cortex, root specific gravities of about 1.02, acceptable yield, and resistance to fusarium wilt (Fusarium oxysporum f. sp. batatas (Wr.) Snyd. and Hans.), the southern root-knot nematode (Meloidogyne incognita (Kofoid and White) Chitwood) and the following soil insects: the southern potato wireworm (Conoderus falli Lane), the banded cucumber (Diabrotica balteata LeConte), the spotted cucumber beetle (D. undecimpuncta howardi Barber), the elongate flea beetle (Systena elongata (F.)), a white grub (Plectris aliena Chapin), and the sweet-potato flea beetle (Chaetocnema confinis Crotch).
Results from research funded by RAMP (Risk Assessment and Mitigation Program) funds conducted with sweetpotato growers in Mississippi during 2004 and 2005 are discussed. Insects were sampled on a weekly (2004) or biweekly (2005) schedule on land planted to potatoes with and without insecticidal input. Potatoes were harvested from each cooperator's field and evaluated for insect damage one or more times at the end of the season. Insect pest populations in Mississippi sweetpotatoes were relatively low during 2004 and 2005. Under these conditions, the percentage of sweetpotatoes damaged by insects was only slightly reduced by insecticides. Chrysomelid leaf beetles including flea beetles, cucumber beetles and tortoise beetles were the most obvious group of pest insects. The most prominent insect species in sweep net samples during the season was the sweetpotato flea beetle, however damage by this pest was negligible. The most damaging insect based on our evaluation of root damage was the twelve-spotted cucumber beetle. Root feeding by whitefringed beetles, white grubs, and sugarcane beetles was sporadic within the fields in the study, and damage by these insects was generally minimal in 2004 and 2005. Preliminary assessments of the effect of crops planted the year previous to the planting of sweetpotatoes indicate the following order of greater to lesser insect damage: pasture, soybeans, corn, sweetpotato, and cotton. Delay of harvest beyond the optimum harvest date tended to increase insect damage in marketable roots. Pesticide evaluations associated with the study indicate that some reduction in damaged roots may be derived from application of a soil-incorporated insecticide at lay by.
Many growers in the St. Louis metro east area in Illinois are growing a diversity of vegetable products to satisfy local market demand, including many Asian vegetables. In 2003 and 2004, an experiment was conducted at a grower location in Belleville, Ill., to evaluate the effect of tillage method (tillage vs. no-tillage) following no-tillage corn (Zea mays) and insecticide treatment (imidacloprid, carbaryl, and none) on growth and productivity of three Asian eggplant (Solanum melongena) cultivars (`Ichiban', `Little Fingers', and `Millionaire'). Regardless of cultivar, imidacloprid resulted in greater plant growth for most of the growing season, resulting in higher early and total-season yields compared to the other insecticide treatments. Flea beetle (numerous species, including Epitrix fuscula and Epitrix cucumeris) damage to eggplants can be severe during the early part of the growing season in southern Illinois, which can drastically reduce plant growth and subsequent yields. Although carbaryl was applied at 10-d intervals for most of the growing season, flea beetle damage was similar to the no insecticide treatment and resulted in significant growth reduction and yield loss compared to imidacloprid. Tillage methods did not differ (P > 0.05) for Asian eggplant productivity or flea beetle damage. Cultivar performance was similar over the tillage method and insecticide treatment as no significant interactions (P > 0.05) were detected. However, cultivars differed for productivity with `Millionaire' and `Ichiban' generally providing higher marketable and total yields than `Little Fingers'.
The reactions of eight sweetpotato [Ipomoea batatas (L.) Lam.] introductions were categorized for root damage by wireworms, Diabrotica sp., Systena sp. (WDS), sweetpotato flea beetle (SPFB), and grubs. Clones were compared with resistant (`Regal') and susceptible (`SC-1149-19') entries. The number of resistant clones for the WDS, SPFB, and grubs were three, four, and one, respectively, intermediate five, four, and one, and susceptible zero, zero, and six, respectively. This test demonstrated that significant levels of soil insect resistance exist in these sweetpotato introductions for use by plant breeders.