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Todd Wehner, James McCreight, Roger Ellis, and Mariana Jooste

A germplasm expedition was organized to collect seeds in the Republic of South Africa. There was an abundance of wild cucurbits there in 1996 because of an unusually rainy summer. Southern Africa is a major center of diversity for melons of Cucumis and Citrullus, and there were many plants with mature fruits along roadsides, and in other areas that had been recently disturbed. The team met in Johannesburg on 25 Apr. 1996, and covered 4213 km (passing through 35 cities and towns) located in four provinces in the northern half of the country. The expedition passed through Pretoria, Potgietersrus, Elisras, Zeerust, Bray, Van Zylsrus, Kalahari Gemsbok Nat. Park, Upington, Postmasburg, Vryburg, and Derdepoort, and visited areas bordering Zimbabwe, Botswana, and Namibia. In 9 days, 112 accessions were collected belonging to 10 species of six genera (Acanthosicyos, Citrullus, Coccinia, Cucumis, Momordica, and Zehneria). Plant, soil and geographic data were recorded for each accession. Data and seeds for the 112 accessions were added to the germplasm collections of the two countries, and can be obtained free from the USDA by interested researchers.

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Ryan S. Donahoo, William W. Turechek, Judy A. Thies, and Chandrasekar S. Kousik

chili peppers, the pathogen is also known to cause crown and fruit rot on many cucurbit genera ( Gubler and Davis, 1996 ). Since the 1940s, losses to cucurbit growers, particularly in the eastern United States, have been so severe that either production

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Matthew A. Cutulle, Howard F. Harrison Jr., Chandresakar S. Kousik, Phillip A. Wadl, and Amnon Levi

herbicide clomazone ( Anonymous, 2005 ) is widely used in cucurbit crop production in the United States. Clomazone controls many important annual weeds such as barnyardgrass [ Echinochloa crus-galli (L.) Beauv], velvetleaf ( Abutilon theophrasti Medicus

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Jesse Wimer, Debra Inglis, and Carol Miles

. (2000) are the only researchers to date that have carried out such an experiment. These researchers screened 33 cucurbit rootstocks for resistance to V. dahliae in Greece and found some degree of tolerance in zucchini, pumpkin, and bottle gourd, but

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Marlee A. Trandel, Penelope Perkins-Veazie, and Jonathan Schultheis

, ). Flesh firmness in pounds was determined using a Penetrometer FT 011 (range, 1–11 lb/4.4–44 N) with a 1.11-cm-diameter plunger tip (QA Supplies LLC, Norfolk, VA). Firmness readings were

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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.

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Francisco Javier Palomares-Rius, Ana Garcés-Claver, María Belén Picó, Cristina Esteras, Fernando Juan Yuste-Lisbona, and María Luisa Gómez-Guillamón

mildew incited by Podosphaera xanthii (Castagne) U. Braun & N. Shishkoff ( Shishkoff, 2000 ) and the yellowing incited by Cucurbit yellow stunting disorder virus (CYSDV) and the incidence of the cotton-melon aphid, Aphis gossypii are three of the

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Amnon Levi, John Coffey, Laura Massey, Nihat Guner, Elad Oren, Yaakov Tadmor, and Kai-shu Ling

PRSV-W, previously known as watermelon mosaic virus-1 (WMV-1), is an important potyvirus causing significant economic damage to cucurbit crops ( Bateson et al., 2002 ). Occurrence of PRSV-W in cucurbit fields coincides with increased aphid

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Xianzhi Zhou, Yufen Wu, Sheng Chen, Yang Chen, Weiguang Zhang, Xintao Sun, and Yijie Zhao

effective, economical, and practical measure for controlling FOM ( Martyn and Miller, 1996 ). In the event that a resistant cultivar is not available in a given area, the use of other cucurbit species not susceptible to FOM as rootstocks for grafting

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Amnon Levi and Kai-shu Ling

Zucchini yellow mosaic virus Theor. Appl. Genet. 120 191 200 Provvidenti, R. Gonsalves, D. Humaydan, H.S. 1984 Occurrence of Zucchini yellow mosaic virus in cucurbits from Connecticut, New York, Florida, and California Plant Dis. 68 443 446 Provvidenti, R