Aphis gossypii Glover is a destructive pest of over two dozen crops world wide Damage to a few of these crops is due to direct feeding, but for most of these crops its impact is through its role as a virus vector As expected, this has resulted in many articles dealing with methods of controlling this insect The aphid has the ability to become resistant to many pesticides and there is growing concern over environmental impacts of pesticide use As a result, manipulation of the agroecosystem will play an ever increasing role in the management of this insect Most aspects of the biology of this aphid are covered in this review The recurrent theme centers around the importance of host plant influences on the biology of the aphid In addition to examining the literature on the biology of the aphid, a large section is devoted to organisms which influence mortality in the aphid, and to aphid borne viruses transmitted by this aphid This review covers the literature from 1912 to 1995, but articles on aphid management (eg pesticide efficacy, planting date) were omitted except where they deal with the aphid's biology or ecology Research on the biology of this aphid has been heavily skewed into several disparate categories First, research has focused on the influence of host plant and temperature on the reproductive rate of this aphid Second, research has focused on the cause for alate production such as nutritional stress, other nutritional factors, crowding, and temperature Third, research has focused on the viral borne pathogens transmitted by this aphid Three specific cases are highlighted: citrus tristeza, cucumber mosaic virus, and the potyviruses Last, research has focused on the role of organisms which feed on this aphid Due to the complexity of research possible in this area, very little research has explored the effect of these "beneficial organisms" on life history traits of this aphid

Biology and ecology of Aphis gossypii glover (Homoptera: Aphididae)

Recent outbreaks of defoliating insects on trees and shrubs used for landscaping major roads in the U.K. are reported. The reasons for some outbreaks were investigated with special reference to effects of the roadside environment. An outbreak of Phalera bucephala on Fagus sylvatia was examined each year between 1975 and 1979 and one of Euproctis similis on Crataegus monogyna from 1975-1978. The nitrogen content of vegetation near a heavily used motorway was greatly enhanced, probably by oxides of nitrogen emitted from vehicle exhausts. The increased nitrogen content of the plants probably increases the insect populations. The outbreaks could not be explained by relaxation of predation.

Outbreaks of insect herbivores on plants along motorways in the United Kingdom.

The objective of our research was to identify alternatives to synthetic pesticide treatments to prevent aphid outbreaks in greenhouse lettuce crops. In the laboratory, we determined the susceptibility of three lettuce-infesting aphid species, Macrosiphum euphorbiae (Thomas), Myzus persicae (Sulzer), and Nasonovia ribisnigri (Mosley), to the hyphomycete Verticillium lecanii (Viegas) (strain Vertalec), the plant triterpenoid molecule azadirachtin (BioNeem), and an insecticidal soap (Safer’s). Estimated LC50 and LT50 obtained in the laboratory indicated that the three aphid species were susceptible to the entomopathogenic fungus, the plant extract, and the soap. Under greenhouse conditions, we assessed the potential of the three pesticides to reduce aphid populations and compared it with that of a synthetic insecticide, the organophosphate Malathion. Greenhouse experiments demonstrated that all three pesticides significantly reduced the population of each aphid species compared with the untreated plants. This study also revealed differences in aphid susceptibility between aphid species and between laboratory bioassays and greenhouse trials. The high initial aphid densities, difficulties to reach the aphids on the undersurface of leaves, stains left by Vertalec on the harvested lettuce, and high cosmetic standards for lettuce mitigated the performance of the insecticides. The potential of using Vertalec, BioNeem, and Safer’s soap for the control of lettuce aphids is discussed in relation to aphid species and crop management.

https://bioone.org/journals/Environmental-Entomology/volume-29/issue-3/0046-225X-29.3.568/Dose-Response-Susceptibility-of-Pest-Aphids-Homoptera--Aphididae-and/10.1603/0046-225X-29.3.568.pdf

Dose-Response Susceptibility of Pest Aphids (Homoptera: Aphididae) and their Control on Hydroponically Grown Lettuce with the Entomopathogenic Fungus Verticillium lecanii, Azadirachtin, and Insecticidal Soap

Les modeles de maladies des insectes sont examines en les comparant aux modeles epidemiologiques generaux et les modeles du parasitisme. Leurs contributions aux theories ecologiques et epidemiologiques sont discutes. Le lien entre les modeles epizootiologiques et les etudes empiriques est discute pour apporter de nouveaux apercus sur la dynamique des populations d'hote et de pathogene

Epizootiological Models of Insect Diseases

(1) Effects of the roadside atmosphere were investigated by placing pots of Lolium perenne (L.) at different distances from the roadside. At each distance, pots were watered with a factorial combination of treatments: high or low nitrogen, with or without sodium chloride. (2) Plants closest to the road attained highest dry weight and showed a trend towards higher total nitrogen content during the course of the experiment. These effects were most marked in plants given a low nitrogen treatment, similar to the nutrient status of roadside soils. (3) Low nitrogen plants given a salt treatment (to simulate de-icing salt) showed a significant increase in dry weight and soluble nitrogen content close to the road. This suggests that salt in roadside soils may increase the availability of nitrogen from NO, to plants. (4) The higher nitrogen content of plants close to the road correlates with more rapid increase of aphid numbers on these plants.

Effects of roadside conditions on plants and insects. I: Atmospheric conditions

A specially formulated soap spray was effective for removal of Aphis gossypii Glover and A. spiraecola Patch on highway plantings of Pyracantha in California. Water alone produced a removal rate of 46–47% for both species, and a general pattern of increased removal rate with higher concentrations of the soap solution was noted. The maximum soap concentration tested, 0.1%, produced removal rates of 72 and 79% for A. spiraecola and A. gossypii , respectively.

Suppression of Populations of Aphis gossypii and A. spiraecola by Soap Sprays

Five commercial formulations ofBacillus thuringiensis (Berliner) were found to be effective for control of larvae of the red-humped caterpillar,Schizura concinna (Smith & Abbot), an important defoliator of broad-leaved trees in California. The formulations tested were Biotrol® BTB 183 25 W, Biotrol® XK, Dipel®, Thuricide® HPC, and Thuricide® 90TS 950T. As a result of these trials,B. thuringiensis replaced chemical insecticides for the control of this pest in 1970, and has provided effective control as part of an operational pest management programme for four years.

Nancy F. Coe

Papers

Suppression of Populations of Aphis gossypii and A. spiraecola by Soap Sprays

The effectiveness of Bacillus thuringiensis formulations for the control of larvae of Schizura concinna on Cercis occidentalis trees in California

Development of a model for prediction of target insect mortality following field application of a Bacillus thuringiensis formulation