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Susan L.F. Meyer

Two strains of the fungus Verticillium lecanii (A. Zimmermann) Viégas were studied as potential biocontrol agents for root-knot nematode (Meloidogyne incognita (Kofoid & White) Chitwood) on cantaloupe (Cucumis melo L.). For the study, pots were filled with soil that had been inoculated with M. incognita (inoculum was applied at two levels: 1000 and 5000 eggs/pot). Each fungus strain was applied individually by pouring an aqueous suspension (made from a wettable granule formulation) into the inoculated soil. Controls received water only. One cantaloupe seedling was then transplanted into each pot. Plants were grown for 55 days in the greenhouse, and then harvested and assessed for root and shoot growth and for nematode egg production. In pots inoculated with 1000 eggs/plant, neither fungus strain affected nematode egg numbers. At the 5000 eggs/plant inoculum level, both strains of the fungus suppressed egg numbers (counts were 28% and 31% less than water controls). Neither strain of V. lecanii affected the number of eggs embedded in root galls; the fungus suppressed nematode population numbers overall solely by affecting the number of eggs located outside of root tissues. Both fungus strains were also autoclaved and then applied to soil, to test for effects of nonviable fungus. In pots inoculated with 5000 eggs, application of one autoclaved strain resulted in a 35% suppression in egg numbers after 55 days, suggesting that the fungus produced a heat-stable substance deleterious to the nematode.

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Raymond A. Cloyd, Amy Dickinson, Richard A. Larson and Karen A. Marley

have been used to collect fungus gnat species in the family Mycetophilidae ( Mikolajczyk, 2001 ). Fungus gnats, Bradysia spp. (Diptera: Sciaridae), are major pests in greenhouses ( Dennis, 1978 ; Hamlen and Mead, 1979 ). Although fungus gnat adults

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Raymond A. Cloyd, Karen A. Marley, Richard A. Larson and Bari Arieli

Fungus gnats ( Bradysia spp.) are common insect pests of greenhouse-grown crops ( Dennis, 1978 ; Hamlen and Mead, 1979 ). The adult flies are considered a nuisance causing minimal direct plant damage ( Cloyd, 2000 ); however, eggs laid by adult

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Raymond A. Cloyd and Amy Dickinson

The soft-bodied larvae of fungus gnats ( Bradysia spp.) reside in growing medium and require constant moisture for survival ( Ellisor, 1934 ). Moisture content is an essential factor responsible for the development and survival of insect stages

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Lawrence W. Zettler, Sarah B. Poulter, Kris I. McDonald and Scott L. Stewart

; Table 1 ). As a result of limited seed availability, seven replicate plates were prepared per media treatment. Each plate was inoculated with a pure culture of the mycorrhizal fungus Epulorhiza repens (Bernard) Moore (UAMH 9824) by adding a 1-cm 3

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Kaori Itagaki, Toshio Shibuya, Motoaki Tojo, Ryosuke Endo and Yoshiaki Kitaya

fungus P. xanthii , on leaves of cucumber ( C. sativus L.) acclimatized to [CO 2 ] levels both lower and higher than atmospheric, and investigated the relationships between susceptibility and leaf properties. The goal was to evaluate plant

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Nathan J. Herrick and Raymond A. Cloyd

Fungus gnat, Bradysia sp. nr. coprophila (Lintner) (Diptera: Sciaridae), larvae can damage plants grown in greenhouse production systems, especially during propagation ( Cloyd, 2000 ). Fungus gnat larvae feed on plant roots, which inhibits the

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Raymond A. Cloyd, Karen A. Marley, Richard A. Larson and Bari Arieli

Fungus gnats ( Bradysia spp.) are common insect pests of greenhouse-grown crops ( Dennis, 1978 ; Hamlen and Mead, 1979 ). The adults are primarily considered a nuisance causing minimal actual plant damage ( Cloyd, 2000 ), although the eggs laid

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Jose A. Oliveira, Ana B. Monteagudo, Suleiman S. Bughrara, Jose L. Martínez, Ana Salas, Esther Novo-Uzal and Federico Pomar

relationships in 34 Iranian fescue accessions. The fungus Sclerotinia homoeocarpa F.T. Bennett causes dollar spot, a leaf disease of closely mowed turf throughout the world ( Bonos et al., 2003 ). Symptoms appear as bleached spots approximately the size of a

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Amy L. Raudenbush, Raymond A. Cloyd and Erik R. Echegaray

Fungus gnats are a commonly encountered insect pest of greenhouses ( Dennis, 1978 ; Hamlen and Mead, 1979 ) and are typically a problem in moist environments such as those that occur in propagation or plug production ( Cloyd, 2000 ). Adults cause