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Full-Text Articles in Life Sciences
A Review Of The Nearctic Species Of The Thrips-Attacking Genus Ceranisus Walker (Hymenoptera: Eulophidae), S. V. Triapitsyn, David H. Headrick
A Review Of The Nearctic Species Of The Thrips-Attacking Genus Ceranisus Walker (Hymenoptera: Eulophidae), S. V. Triapitsyn, David H. Headrick
Horticulture and Crop Science
The thrips-attacking Eulophidae (subfamily Entedoninae) known from the Nearctic region are reviewed. One new species, Ceranisus loomansi, is described. Four other species of Ceranisus are redescribed and illustrated based mainly on a study of their type specimens as well as on additional material from Arizona, California, Hawaii, Mississippi and Japan. Lectotypes are designated for Ceranisus americensis (Girault), C. nubilipennis (Williams) and C. russelli (Crawford). A key to eight species belonging to four entedonine thrips-attacking genera is given, and host associations are indicated for those species.
Spider (Araneae) Species Composition And Seasonal Abundance In San Joaquin Valley Grape Vineyards, Michael J. Costello, Kent M. Daane
Spider (Araneae) Species Composition And Seasonal Abundance In San Joaquin Valley Grape Vineyards, Michael J. Costello, Kent M. Daane
Horticulture and Crop Science
As part of an investigation to estimate the effect of resident spider populations on Erythroneura variabilis Beamer, spider species composition, relative abundance, and seasonal occurrence were determined. Spiders were sampled monthly during the 1992 and 1993 growing seasons; their numbers were pooled and analyzed for species diversity using the Renkonen index of similarity and cluster analysis. Twenty-seven species of spiders were recorded, representing 14 families. The most common species were Cheiracanthium inclusum (Hentz), Trachelas pacificus (Chamberlin and Ivie), Theridion dilutum Levi, Theridion melanurum Hahn, Oxyopes scalaris Hentz, Oxyopes salticus Hentz, Hololena nedra Chamberlin and Ivie, and Metaphidippus vitis (Cockerell). Three …
Spectral Reflectance From A Broccoli Crop With Vegetation Or Soilias Background: Influence On Immigration By Brevicoryne Brassicae And Myzus Persicae, Michael J. Costello
Spectral Reflectance From A Broccoli Crop With Vegetation Or Soilias Background: Influence On Immigration By Brevicoryne Brassicae And Myzus Persicae, Michael J. Costello
Horticulture and Crop Science
Light reflectance in five wavebands of the spectrum was measured from broccoli (Brassicae oleracea var.botrytis [L].) interplanted with leguminous cover crops (cover crop background) or broccoli grown as monoculture (bare soil background), and fertilized with compost or synthetic fertilizer. Alate Brevicoryne brassicae (L.) and Myzus persicae (Sulzer) (Homoptera: Aphididae) were monitored in yellow pan water traps and on broccoli leaves. Reflectance intensity was higher with a background of bare soil at all wavebands except blue (400–455 nm) in the early-season. Intensity decreased as broccoli canopy cover increased at all wavebands except blue and green (515–550 nm), declining-most dramatically in …
Abundance, Growth Rate And Parasitism Of Brevicoryne Brassicae And Myzus Persicae (Homoptera: Aphididae) On Broccoli Grown In Living Mulches, Michael J. Costello, Miguel A. Altieri
Abundance, Growth Rate And Parasitism Of Brevicoryne Brassicae And Myzus Persicae (Homoptera: Aphididae) On Broccoli Grown In Living Mulches, Michael J. Costello, Miguel A. Altieri
Horticulture and Crop Science
In 1990 and 1991, populations of the cabbage aphid, Brevicoryne brassicae, and the green peach aphid, Myzus persicae, were monitored on broccoli interplanted with three leguminous cover crops (the living mulches) and compared with broccoli without cover crop (clean cultivation). The cover crops used were white clover (Trifolium repens L.), strawberry clover (Trifolium fragiferum L.) and a mixture of birdsfoot trefoil (Lotus corniculatus L.) and red clover (Trifolium praetense L.). Fertilizer was applied as compost or synthetic fertilizer crossed with cropping system regime. Brevicoryne brassicae can reach pest status in Brassica cropping systems, whereas …
Life History And Description Of Immature Stages Of Euaresta Stigmatica (Diptera: Tephritidae) On Ambrosia Spp. (Asteraceae) In Southern California, David H. Headrick, Richard D. Goeden, Jeffrey A. Teerink
Life History And Description Of Immature Stages Of Euaresta Stigmatica (Diptera: Tephritidae) On Ambrosia Spp. (Asteraceae) In Southern California, David H. Headrick, Richard D. Goeden, Jeffrey A. Teerink
Horticulture and Crop Science
Euaresta stigmatica Coquillett is bivoltine and nearly monophagous on four native ragweeds, Ambrosia spp. (Asteraceae), in the southwestern United States. In southern California, larvae of the spring (F1) generation develop singly in and feed on one or both ovules of young fruiting involucres of Ambrosia ilicifolia (Gray) Payne, with a small proportion infesting the staminate involucres. Adults emerge after ≈1 mo, with their reproductive organs immature. The F2 generation develops in the involucres of fall-blooming Ambrosia acanthicarpa Hooker. The egg is described and illustrated for the first time for any species of Euaresta. First, second, and …
Behaviors Of Female Eretmocerus Sp. Nr. Californicus (Hymenoptera: Aphelinidae) Attacking Bemisia Argentifolii (Homoptera: Aleyrodidae) On Sweet Potato, David H. Headrick, Thomas S. Bellows, Jr., Thomas M. Perring
Behaviors Of Female Eretmocerus Sp. Nr. Californicus (Hymenoptera: Aphelinidae) Attacking Bemisia Argentifolii (Homoptera: Aleyrodidae) On Sweet Potato, David H. Headrick, Thomas S. Bellows, Jr., Thomas M. Perring
Horticulture and Crop Science
Behaviors of Eretmocerus sp. nr. californicus Howard females on Bemisia argentifolii Bellows & Perring infesting sweet potato, Ipomoea batatas (L.) Lain, were described and quantified. Walking speeds of up to 1.3 mm/s were calculated for females searching for host whitefly nymphs on sweet potato leaves. Females encountered all host stages during searching with approximately the same relative frequency as their relative abundance (average of 17.03% of hosts available were encountered). Females also arrested and antennated all of the host stages with the same relative frequency as their encounter rate (62.8%). Females showed a clear and significant preference for probing second …
Split-Root Nutrition Of Sweetpotato In Hydroponic Systems, M. A. Sherif, P. A. Loretan, A. A. Trotman, D. G. Mortley, J. Y. Lu, Lauren C. Garner
Split-Root Nutrition Of Sweetpotato In Hydroponic Systems, M. A. Sherif, P. A. Loretan, A. A. Trotman, D. G. Mortley, J. Y. Lu, Lauren C. Garner
Horticulture and Crop Science
Nutrient film technique (NFT) and deep water culture (DWC) hydroponic systems were used in a split-root study of the effect of four treatments on sweetpotato yield, the translocation of assimilates, and microbial population count. ‘TU-155’ cuttings (15 cm) were prerooted for 30 days in sand using deionized water and a modified half-Hoagland (MHH) solution. After 30 days, the plants were removed, and the roots of each were cleaned and split evenly between two sides of a channel (each 15 cm deep by 15 cm wide by 1.2 m long), four plants per channel. Replicated treatments were: MHH/MHH; MHH/Air, MHH/deionized water …