Presence-Absence Sequential Sampling for Cabbage Aphid and Green Peach Aphid (Homoptera: Aphididae) on Brussels Sprouts

Abstract California’s central coast differs from many agricultural areas in the U.S., which feature large tracts of monoculture production fields and relatively simple landscapes. Known as the nations salad bowl, and producing up to 90% of U.S. production of lettuces, broccoli and Brussels sprouts, this region is a mosaic of fresh vegetable fields, coastal meadow, chaparral shrubs, riparian and woodland habitat. We tested for relationships between the percent cover of crops, riparian and other natural landscape vegetation and the species richness of parasitic wasps and flies foraging in crops, such as broccoli, kale and cauliflower, and interpreted our results with respect to the decrease in natural habitat and increase in cropland cover prompted by a local microbial contamination event in 2006. Our key results are that: (1) as cropland cover in the landscape increased, fewer species of parasitoids were captured in the crop field, (2) parasitoid richness overall was positively associated with the amount of riparian and other natural vegetation in the surrounding 500m, (3) different groups of parasitoids were associated with unique types of natural vegetation, and (4) parasitism rates of sentinel cabbage aphid and cabbage looper pests were correlated with landscape vegetation features according to which parasitoids caused the mortality. Although individual species of parasitoids may thrive in landscapes that are predominantly short season crops, the robust associations found in this study across specialist and generalist parasitoids and different taxa (tachinid flies, ichneumon wasps, braconid wasps) shows that recent food safety practices targeting removal of natural vegetation around vegetable fields in an attempt to eliminate wildlife may harm natural enemy communities and reduce ecosystem services. We argue that enhancing biological diversity is a key goal for transforming agroecosystems for future productivity, sustainability and public health.

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Feeding location of aphid prey affects life history traits of a native predator

10.1101/429415 ◽

2018 ◽

Author(s):

Ximena Cibils-Stewart ◽

James Nechols ◽

Kristopher Giles ◽

Brian P. McCornack

Keyword(s):

Community Dynamics ◽

Plant Defenses ◽

Green Peach Aphid ◽

Feeding Preference ◽

Aphid Species ◽

Brassica Napus L ◽

Cabbage Aphid ◽

Prey Suitability ◽

Aphid Prey ◽

Consumption Rates

AbstractThe green peach aphid (GPA), Myzus persicae S., and the cabbage aphid (CA), Brevicoryne brassicae L., exhibit a feeding preference when exposed to different canola (Brassica napus L.) plant structures. Preference may be associated with the concentration and/or composition of allelochemicals; specifically, glucosinolates (GLS). Furthermore, each aphid species employs a different strategy for tolerating plant defensive chemistry; GPA excretes glucosinolates while CA sequesters these toxic compounds. Given these different detoxification mechanisms, it is possible that both feeding location and aphid species may affect prey suitability for Hippodamia convergens larvae. We conducted a factorial laboratory experiment to evaluate whether one or both factors impacted predator fitness. We hypothesized that plant structures with higher GLS concentrations will negatively affect the development and survival of immature predators, which will also vary based on prey detoxification strategies. Results confirm that when predators fed on either aphid species reared on canola structures having lower GLS concentrations, development was faster than when they fed on aphids reared on structures having higher GLS. Although predators consumed more GPA than CA, consumption rates did not differ between rearing location for GPA, but fewer CA were consumed when reared on reproductive canola parts. These findings suggest that: 1) plant-mediated differences in prey quality exist for canola aphids; 2) the type of adaptation used by aphids to overcome plant defenses have important consequences for prey suitability; and 3) reduced feeding by H. convergens larvae on unsuitable prey may offset deleterious effects of plant defenses against aphid pests. By evaluating source-sink dynamics at the plant level, we can further understand trophic interactions involving plant defenses and how these interactions may influence community dynamics and structure.

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POPULATION DYNAMICS OF APHIDS ON BROCCOLI IN THE MEXICAN BAJIO VALLEY.

HortScience ◽

10.21273/hortsci.25.9.1132a ◽

1990 ◽

Vol 25 (9) ◽

pp. 1132a-1132

Author(s):

Alfonso Hernández-Barajas ◽

José Luis Vera-Medina ◽

Dr. Benito Alvarado-Rodriguez

Keyword(s):

Population Dynamics ◽

Myzus Persicae ◽

Green Peach Aphid ◽

Parasitic Wasp ◽

Brevicoryne Brassicae ◽

Aphid Population ◽

Cabbage Aphid ◽

Prevalent Species ◽

Natural Parasitism ◽

Made In

During a two-year-period, a study was made in the field in order to know the ocurrence of aphids in the broccoli crop. It was possible to know that the total aphid population is higher in winter plantings where more than 240 aphids/plant were found Spring and fall plantings, in comparison, less than 20 aphids/plant were encountered. The species more common were the cabbage aphid (Brevicoryne brassicae L.), the most prevalent species in the crop, getting more than 80% of the population, and the green peach aphid (Myzus persicae Sulzer) with a little bit more than 17% of the total. The natural parasitism in all plantings was around 17%. By species, parasitism in B. brassicae was higher in springs (70% of the total) and fall plantings where the parasitic wasp Diaretiella rapa e (MacIntosh) was probably more active. The sane pattern was obtained for M. persicae, in which the parasitism was again higher in spring and fall plantings (20% of the total) and very low during the winter. Regarding leaf preference, a very defined pattern was found in the M. persicae than for B. brassicae.

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Managing Western Flower Thrips (Thysanoptera: Thripidae) on Lettuce and Green Peach Aphid and Cabbage Aphid (Hemiptera: Aphididae) on Broccoli with Chemical Insecticides and the Entomopathogenic Fungus Beauveria bassiana (Hypocreales: Clavicipitaceae)

The Open Plant Science Journal ◽

10.2174/1874294701710010021 ◽

2017 ◽

Vol 10 (1) ◽

pp. 21-28 ◽

Cited By ~ 4

Author(s):

Surendra K. Dara

Keyword(s):

Beauveria Bassiana ◽

Entomopathogenic Fungus ◽

Frankliniella Occidentalis ◽

Insect Pests ◽

Green Peach Aphid ◽

Western Flower Thrips ◽

Good Control ◽

Vegetable Crops ◽

Cabbage Aphid ◽

Flower Thrips

Aims:Lettuce and broccoli are high value vegetable crops in California. The western flower thrips,Frankliniella occidentalison lettuce, and the cabbage aphid,Brevicoryne brassicaeand the green peach aphid,Myzus persicaeon broccoli are important insect pests that are frequently managed with chemical insecticides.Observation:Efficacy of various chemical insecticides and the entomopathogenic fungusBeauveria bassianawas evaluated against these pests in field studies in the Santa Maria area of California. Some insecticides varied in their efficacy againstF. occidentalisfrom year to year and against different aphid species.Conclusion:A new insecticide sulfoxaflor provided good control of aphids on broccoli.Beauveria bassianademonstrated a potential for broccoli and lettuce integrated pest management.

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STUDIES OF CABBAGE APHID INFESTATIONS ON BRUSSELS SPROUTS, 1951

Plant Pathology ◽

10.1111/j.1365-3059.1953.tb00629.x ◽

1953 ◽

Vol 2 (1) ◽

pp. 25-30 ◽

Cited By ~ 3

Author(s):

A. Ibbotson

Keyword(s):

Brussels Sprouts ◽

Cabbage Aphid

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