Striped and spotted cucumber beetles are important insect pests of cucurbits and vectors of the causal agent of bacterial wilt ( Erwinia tracheiphila ), the most serious disease threat of muskmelon in Kentucky ( Hoffman, 1998 ; Rowell et al., 2002
Gary R. Cline, John D. Sedlacek, Steve L. Hillman, Sharon K. Parker and Anthony F. Silvernail
Ahmad Shah Mohammadi, Elizabeth T. Maynard, Ricky E. Foster, Daniel S. Egel and Kevin T. McNamara
-sutured “charentais” types. Honeydew melons marketed in the United States are primarily green-fleshed with smooth rinds and represent 20% of the country’s muskmelon production ( USDA-NASS, 2016 ). Striped cucumber beetle ( A. vittatum ) is the most serious insect pest
Gerald E. Brust and Karen K. Rane
Ten muskmelon (Cucumis melo L.) cultivars were tested for their susceptibility to bacterial wilt, caused by Erwinia trucheiphila (Smith) Bergey, Harrison, Breed, Hammer and Huntoon and vectored by the striped cucumber beetle Acalymma vittatum (F). `Superstar', `Rising Star', `Pulsar', `Caravelle', `Cordele', `Legend', `Makdimon', `Galia', `Rocky Sweet', and `Passport' were used in field studies to determine the number of striped cucumber beetles, feeding damage, and incidence of bacterial wilt. `Makdimon' and `Rocky Sweet' hosted significantly more beetles than the other cultivars. These two cultivars and `Legend' and `Cordele' had much more feeding damage and a significantly higher incidence of bacterial wilt than the others. A greenhouse experiment was conducted with seven of the cultivars to test their susceptibility to bacterial wilt when directly inoculated with the causal agent. All cultivars were equally susceptible to the disease when it was introduced directly into the plant. Selective feeding by striped cucumber beetles was probably most responsible for `Makdimon', `Rocky Sweet', `Legend', and `Cordele' having greater incidences of bacterial wilt than the other cultivars.
John S. Caldwell and Paul Clarke
Cucumber (Cucumis sativus L.) and squash (Cucurbita pepo L.) were grown in a replicated trial on three types of plastic mulch: solid black plastic mulch, solid aluminum-coated plastic mulch with a silver reflective appearance, and black plastic mulch with two aluminum-coated strips attached. Striped cucumber beetle (Acalymma vittata Fabricius) and spotted cucumber beetle (Diabrotica undecimpunctata howardi Barber) (Coleoptera: Chrysomelidae) counts on yellow sticky cards were obtained over eight weekly samplings. For cucumber, on the peak beetle population date, there were six times as many striped cucumber beetles in solid black plastic mulch as in aluminum-coated plastic mulch, and nearly three times as many as in black plastic mulch with aluminum strips. For squash, both striped and spotted cucumber beetle counts were significantly higher on solid black plastic mulch on three peak sampling dates than on aluminum-coated plastic mulch and black plastic mulch with aluminum strips, with counts 4.9 to 5.5 times higher in solid black plastic mulch than in aluminum-coated plastic mulch, and 2.2 to 2.6 times higher than in black plastic mulch with aluminum strips. Using a threshold of 15 beetles/sticky card, no insecticidal applications were needed on solid aluminum-coated mulch, while an average of 1.8 insecticidal applications were needed on solid black plastic mulch, and 0.8 insecticidal applications on black plastic mulch with aluminum strips. The cost of solid black plastic mulch and its insecticidal applications, $186/acre ($459/ha), was $102/acre ($252/ha) less than the cost of aluminum-coated plastic mulch without insecticidal application, $288/acre ($711/ha). However, squash fruit from plants grown on aluminum-coated plastic mulch could be direct marketed as pesticide-free, at a price 25% higher than fruit on which pesticide had been applied. For an average yield in Virginia of 600 boxes/acre (1,482 boxes/ha) [20 lb/box (9 kg/box)] of squash, this translates to a $1,200/acre ($2,964/ha) increase in revenue. Yield on aluminum-coated plastic mulch was delayed by one week, but there were no significant differences in cumulative yield over 14 harvests.
J.R. Andino and C.E. Motsenbocker
Colored plastic mulches were evaluated for their effect on the production of a triploid (`Honeyheart') and a diploid (`Sangria') watermelon cultivar during the spring growing season. Colored mulches affected cucumber beetle populations; the SRM-Red (Selective Reflective Mulch) and yellow plastic mulch plots had among the highest cucumber beetle populations recorded in both cultivars while the silver-reflective and the silver-on-black plastic mulches had among the lowest. In general, most mulched plots had longer vines than the bare-ground treatment, with few differences in vine length among treatments by 4 weeks. There were no differences among mulch treatments in first and total `Honeyheart' harvest while the IRT-100 (infrared transmitting; green), PST (photosynthetic reduced transmitting), and silver-on-black plastic mulches had the highest first `Sangria' harvest and among the highest total `Sangria' harvest. Plants in plastic mulch treatments had higher yields as a result of higher fruit number per area. Fruit weight, length, and diameter and total soluble solids for both cultivars were not affected by colored plastic mulch treatments.
Russell Nagata*, Gregg Nuessly and Heather McAuslane
Host plant resistance is a key element in a viable integrated pest management plan. Resistance to plant feeding was observed on Valmaine cos lettuce, Lactuca sativa L. to the banded cucumber beetle (BCB), Diabotica balteata (LeConte). In no-choice feeding evaluations, adult BCB contained on three week old Valmaine plants gained less weight, died and fed less than individuals contained on susceptible Tall Guzmaine cos lettuce. Individual female BCB held on Valmaine plants also did not have egg development as in those individual held on Tall Guzmaine. Based on weight gain and feeding damage F1, F2, and F3 segregation data indicates that the resistance factor is recessive in inheritance and controlled by more that one gene.
Jason Walker, John S. Caldwell and Robert H. Jones
To assess the value of uncultivated vegetation for control of cucumber beetles, populations of striped (Acalymma vittatum Fabr.), spotted (Diabrotica undecimpunctata howardi Barber), and western cucumber beetles (Acalymma trivittatum Mann.) (Coleoptera: Chrysomelidae) and natural enemy Diptera flies (as an indicator of Celatoria spp. parasitoids), Pennsylvania leatherwings (Chauliognathus pennsylvanicus DeGeer) (Coleoptera: Cantharidae), lady beetles (Coleoptera: Coccinellidae), Hymenoptera wasps, and spiders were monitored with sticky traps on 50-m transects running through a field of Cucumis sativa L. `Arkansas Littleleaf' into bordering uncultivated vegetation. Plant species composition was determined in square plots around each sticky trap by estimating total plant cover and height distribution of plants from 0 to 1.0 m. In both years, numbers of cucumber beetles increased and numbers of Diptera decreased towards the crop. These trends increased monthly to peaks in Aug. 1995 (0.3 to 6.0 striped cucumber beetles; 40.0 to 15.3 Diptera) and July in 1996 (0.1 to 7.1 striped cucumber beetles; 46.7 to 15.5 Diptera). Abundance of individual plant species contributed more to maximum R 2 regression of insect populations than did measures of plant diversity in sampling squares. Diptera were negatively correlated with sweet-vernal grass (r = –0.65 at 0 m) and wild rose (r = –0.62 at 0.5 m) in 1995, and goldenrod (r = –0.31, –0.59, and –0.53 at 0.5, 0.75, and 1.0 m, respectively) in 1996, but positively correlated with wild violets (Viola spp.) (r = +0.38 at 0 m) in 1996. Cucumber beetles were negatively correlated with wild violets (r = –0.30 at 0 m) and white clover (Trifolium repens) (r = –0.37 at 0 m) in 1996. These results suggest that increasing or decreasing specific plants in uncultivated vegetation might be useful for influencing pest and beneficial insect populations in cucurbit production.
Jason Platt, John S. Caldwell and L.T. Kok
Cucumber beetles Acalymma vittatum (Fab.) and Diabrotica undecimpunctata howardi (Barber) (Coleoptera: Chrysomelidae) are major pests of cucurbits, and biological methods are needed for their control. A floral border of buckwheat Fagopyrum esculentum (Moench) was planted perpendicular to Cucumis sativa L. `Arkansas Littleleaf' and Cucurbita pepo L. `Seneca' rows to assess effects on populations of cucumber beetles and the presence of natural enemies. Numbers of Diptera were used as an indicator of potential border attractiveness to natural enemies Celatoria diabroticae (Shimer) and Celatoria setosa (Coquillett) (Diptera: Tachinidae). Sticky traps and modified Malaise traps at increments from the border were used to monitor insect numbers. There was a quadratic decline from 19.5 Diptera in the border to 2.8 Diptera at 20 m from the border in June 1995 and linear declines from 14.8 and 14.2 Diptera in the border to 9.8 and 6.8 Diptera at 36 m in June and Aug. 1996, respectively. Numbers of striped cucumber beetles were variable, with a non-significant (P = 0.08) linear increase from 13.0 insects in the border to 17.5 insects at 36 m in June 1995, but quadratic decreases to 27 m in June, July, and Sept. 1996. Similar declines as distance from the border increased were found in numbers of tachinid flies (Diptera: Tachinidae) and Hymenoptera wasps and Pennsylvania leatherwings, Chauliognathus pennsylvanicus (Deg.) (Coleoptera: Cantharidae) and lady beetles (Coleoptera: Coccinellidae) in 1996. No meaningful effects on cucumber (1995) or squash (1995 and 1996) yield were found. Although the natural populations of Celatoria spp. were not high enough to achieve control, these results suggest that flowering borders may be useful as habitats for releasing natural enemies of cucumber beetles. Numbers of Pennsylvania leatherwings, Chauliognathus pennsylvanicus (Deg.) (Coleoptera: Cantharidae) showed a significant linear decline from 2.1 insects in the border to 0.2 insects at 36 m in June 1996, but no significant relationship was found in 1995 or in Aug. 1996.
Irene Nyambura Mbugua
Field experiments were performed to verify the influence of polyethylene mulches (red, blue, gray, black, and yellow) on the development and yield of two varieties of cucumber (Cucumis sativus), a hybrid, `Turbo' and an open-pollinated, `Marketmore 76'. The influence of the mulches on the population dynamics of the adult striped cucumber beetle (Acalymma vittatum) was also observed. Rhizosphere temperature, reflected surface temperatures, reflected wavelength, vine length, leaf number, leaf area, total fruit produced, and number of marketable fruit were some of the characteristics measured. A split plot experiment in a randomized blocks design with three replications was used. In relation to plant growth and yield, plants grown on red mulch showed the best growth and yield overall compared to blue, gray, black, and yellow colored mulches, The incidence of the cucumber beetles was highest in the yellow colored mulch. The `Turbo' variety had the highest fruit number in almost all of the colors of mulch compared to the open pollinated `Marketmore'. It is suggested that the differential growth and development of cucumbers was influenced by the rhizosphere temperature as well as the light spectrum reflected from the plastic. The response of the beetles to the mulch was mainly attributed to the different wavelengths reflected from the various mulches.
Karen M. Meyer, Greg L. Davis and James R. Steadman
The toxic bait, Adios, was tested with the use of a trap crop in a field experiment at the Univ. of Nebraska during Summer 1998. The insecticide contains the secondary plant metabolites known as cucurbitacins that are highly attractive to the striped and spotted cucumber beetles, Acalymma vittatum and Diabrotica undecimuncata howardi, respectively. These beetles serve as the vector of the bacterial pathogen, Erwinia tracheiphila, which causes severe wilting and eventual death of susceptible cucurbits. The objective of the study was to determine whether treatments of Adios, when applied to a flowering trap crop of resistant squash plants, would lure the cucumber beetles away from the susceptible cucumber plants and reduce bacterial wilt. The study compared the effectiveness of a sprayed trap crop, the direct application of Adios to the cucumber plants and no treatment in a randomized complete-block design. A greater number of beetles were attracted to the sprayed and untreated cucumbers compared to the cucumbers surrounded by the treated trap plants. However, significant numbers of dead beetles were found near the sprayed cucumber plants. Untreated plants showed more feeding damage, diminished fruit quality, and an earlier observation date of wilt symptoms as compared to the other treatments. The treated trap plants and the direct application of Adios were effective in delaying infection in cucumbers compared to the untreated plants in the experimental plots. This treatment may be useful to home gardeners.