Peach Aphid Myzus Persicae Research Articles

Influence of prey host plant on a generalist aphidophagous predator: Episyrphus balteatus (Diptera: Syrphidae)

Secondary plant metabolites (allelochemicals) play a major role in plant-insect interactions. Glucosinolates (GLS) and their degradation products from Brassica species are attractants and feeding stimulants for Brassicaceae specialist insects but are generally repellent and toxic for generalist herbivores. The impact of these compounds on crucifer specialist insects are well known but their effect on generalist predators is still not well documented. The influence of the prey's host plant on both development and reproduction of an aphidophagous beneficial, the hoverfly Episyrphus balteatus, was determined using the cabbage aphid, Brevicoryne brassicae (a specialist) and the peach aphid Myzus persicae (a generalist) reared on two crucifer plants, Brassica napus and Sinapis alba containing low and high GLS levels respectively.The prey and its host plant differently influenced life history parameters of E. balteatus. The predator's rates of development and survival did not vary when it fed on the generalist aphid reared on different host plants. These rates decreased, however, when the predator fed on the specialist aphid reared on the host plant with high GLS content plant versus the host plant with lower GLS content. This aphid host plant combination also negatively affected hoverfly reproduction; lower fecundity was observed. As a result, the fitness of the hoverfly was strongly affected. This study illustrates the importance of tritrophic relations in pest management involving predators. The host plant of the prey can have a major influence on the potential of a biological agent to control herbivore species such as aphids.

Domyzus (nectarosiphon) species other thanm persicae pose a threat to the idaho potato crop?

Green peach aphids (Myzus persicae (Sulzer) ) pose a threat to the Idaho potato (Solanum tuberosum L.) crop primarily because they transmit potato leafroll virus (PLRV). Only colonizing vectors are epidemiologically significant because PLRV is persistently transmitted. Additionally, Idaho winters are severe enough that most permanently anholocyclic aphid species do not establish. It is now accepted that the taxon that has been known asMyzus (Nectarosiphon)persicae (Sulzer) is in fact at least three species (M. persicae, Myzus nicotianae Blackman andMyzus antirrhinii (Macchiati) ). It was not known whether the newly designated species had the potential to damage the Idaho potato crop. The objectives of our research were to determine whetherMyzus (Nectarosiphon) spp. other thanM. persicae occurred naturally in Idaho, whether they could colonize potato and transmit PLRV, and whether they were potentially holocyclic.

Modelling aphid outbreaks

Three different types of model have been used in the past to forecast aphid outbreaks or to understand their causes. These can be considered as empirical, synoptic (sensulato), and functional. Empirical models are results of statistical analyses of observed population data, yielding regression equations relating aphid incidence to various other factors. For example, Vickerman (1978) found that summer aphid numbers on cereals in the UK were negatively related to spring temperatures, an apparent anomaly attributed to the positive influence of spring temperatures on natural enemy populations. Synoptic or lumped-parameter models do not distinguish age-classes and generally consist of one or two equations broadly reflecting the underlying biological processes involved. Whalon & Smilowitz (1979) developed such a model to predict the rate of build-up of green peach aphid (Myzus persicae Linnaeus) populations on potatoes in Pennsylvania. The aim was to provide advance warning of the need to spray and for the mode...

Effect of Three Insect-Borne Virus Diseases on Sugar Beet Seed Production1

Tests to determine the effect of beet yellows and beet western yellows on sugar beets grown for seed were conducted in field plots From 1959 to 1962. The effect of these diseases, alone and in combination with each other and with curly top, was tested. Green peach aphids ( Myzus persicae (Sulzer)) were used as vectors of the yellows viruses and beet leafhoppers ( Circulifer teneltus (Baker)) as vectors of the curly top virus. Both beet yellows and beet western yellows reduced seed yields but did not affect germination. Mixtures of the two yellows viruses caused much greater losses than either one alone, and early infections reduced yields more than later infections. Early spring yellows infection of curly top-resistant beets inoculated with curly top in the fall did not reduce yields more than yellows alone. Spring infection of curly top-susceptible beets with curly top virus had no measurable effect on the seed crop, but when followed by yellows infection, losses were greater than with yellows alone.

Green Peach Aphid Populations on Desert Sugar Beets1

The green peach aphid ( Myzus persicae (Sulzer)) has about nine generations on desert beets between October 15 and March 31. Alatae produced ranged from 15% in low to 99% in high populations. During the 1959-60 season the average production of alatae was more than 25 million per acre, mostly after February 15.

Insecticide Experiments to Control Green Peach Aphid and Pepper Weevil on Peppers

During 1959 and 1960, field experiments on the control of the pepper weevil ( Anthonomus eugenii Cano) were conducted in southern California. Applications of Sevin® (I-naphthyl N -methylearbamate) and, to a lesser extent, a mixture of DDT and parathion, were followed by rapid increases in the green peach aphid ( Myzus persicae (Sulzer)). Effective aphid control was obtained by either Thiodan® (6,7,8,9,10,10-hexachloro-1,5,5a,6,9,9a-hexahydo-6,9-methano-2,4,3-benzodioxathiepin-3-oxide) or Phosdrin® (a mixture of the alpha isomer of 2-carbomethoxy-1-methylvinyl dimethyl phosphate (not less than 60%) and related compounds (not more than 40%)) applied as dusts when needed. Diazinon® ( O,O -diethyl O -2(2-isopropyl-4-methyl-6-pyrimidinyl) phosphorothioate) was less effective. Phosphamidon and malathion failed to control the aphid. A DDT-toxaphene mixture applied for pepper weevil control resulted in mild aphid increases.

Toxicity of Dibrom Vapors to Greenhouse Insects1

The application of liquid concentrates containing Dibrom® (1,2-dibromo-2,2-diehloroethyl dimethyl phosphate) to heating pipes in greenhouses resulted in good control of greenhouse white fly ( Trialeurodes raporariorum (Westwood)), potato aphid ( Maerosiphum enphorbiae (Thomas)), two-spotted spider mite ( Tetranychus telarius (L.)), and other pests on bearing tomatoes. Good control or green peach aphid ( Myzus persicae (Sulzer)) on several types of vegetable and annual flowering plants was also obtained. Mushroom mite ( Tyrophayus putrescentiae (Schrank)) was not satisfactorily controlled by Dibrom vapor treatments. Dibrom vapor treatments killed insects and mites in all parts of the greenhouse with no lingering residue problems.

Effect of Zectran, Sevin, and Other New Carbamate Insecticides Upon Insect Populations Found on Vegetable and Field Crops in Southern California1

Sevin® (1-naphthyl N -methylearbamate) and Zectran® (4-di- methylamino-3,5-xylyl N -methylcarbamate) were evaluated for their effectiveness against insects occurring on the following crops: cauliflower, celery, corn, cotton, peppers, and tomatoes. A 5% Sevin dust provided effective control of the corn earworm (Heliothis zea (Boddie)) on sweet corn; on cotton, Sevin at 2 pounds of toxicant per acre gave evidence of a lasting residual control of cotton leaf perforator ( Bucculatrix thurberiella Busck), salt-marsh caterpillar (Estigmene acrea (Drury)), and cotton bollworm (=corn earworm) larvae. Zectran, applied at from 0.5 to 1 pound per acre, provided excellent control of western flower thrips ( Frankliniella occidentalis is (Pergande), leafminers, ( Liriomyza spp.), and various species of lepidopterous larvae and flea beetles. On cotton, effective residues of Zectran do not seem to persist so long as those of Sevin. Both compounds were destructive to a variety of beneficial insect species on cotton. The addition of piperonyl but oxide did not consistently and markedly increase the toxicity of Sevin to larvae of the cabbage looper ( Trichoplusia ni (Hubner)), beet armyworm ( Spodoptera exigua (Hubner)), cabbage aphid ( Brevicoryne brassicae (L.)), and green peach aphid ( Myzus persicae (Sulzer)) on cauliflower and celery. Five per cent dusts of Bayer 37344 (3,5-dimethyl-4-methylthiophenyl N -methylcarbamate), Bayer 39007 ( o -isopropoxyphenyl N -methyl carbamate), and Union Carbide 10854 ( m -isopropylphenyl N -methyl carbamate) gave fair control of corn earworms on sweet corn. Beet armyworms on celery were not effectively controlled by l.2 pounds per acre of Bayer 37344.

Experiments with Insecticides for Control of the Green Peach Aphid on Potatoes

After the green peach aphid (Myzus persicae (Sulzer)) became tolerant to parathion, field-plot experiments were begun in 1954 to try to find a more effective insecticide. Both multiple and single applications were tested. Endrin and Thiodan® (6,7,8,9,10, 10-hexachloro-1,5,5a, 6,9,9 a -hexahydro-6,9-methano-2,4,3-benzodioxathiepin-3-oxide) gave better control than parathion, but Thiodan was the most effective.

Effect of Curly Top and Cucumber Mosaic Viruses on Cantaloups

Cantaloup plants were inoculated in experimental plots with cucumber mosaic virus (CMV) and curly top virus (CTV) separately and in combination. CMV is transmitted predominantly by the green peach aphid (Myzus persicae (Sulzer)) and CTV only by the beet leafhopper (Circulifer tenellus (Baker)). Inoculations were made when plants were in the six-leaf stage of development. Plants inoculated with CMV, either alone or in combination with CTV, were smaller and produced smaller melons. Size of plants or melons was not affected by CTV alone. Yield of marketable melons was reduced 32% over the uninoculated checks for CTV alone, 40% for CMV, and 68% in plots inoculated with both viruses.

European Corn Borer Control in Potatoes 1

Heavy, natural infestation of Katahdin potatoes by the European corn borer ( Pyrausta nubilalis (Hbn.)) did not affect yields of U. S. No. 1 potatoes. Five insecticides, applied as sprays, gave good control of this insect. They are: DDT, Kepone® (decachlorooctahydro-1,3,4-methano-2H-cyclobuta [cd] pentalen 2-one), phosphamidon, Sevin® (1 naphthyl N -methylcarbamate), and Thiodan® (6,7,8,9,10,10-hexachloro-1,5,5a,6,9,9a-hexahydro-6, 9-methano-2,4,3-benzodioxathiepin 3-oxide). Phorate, applied to the soil at planting time failed to give control of the borer. The green peach aphid ( Myzus persicae (Sulz.)) was effectively controlled by phorate, phosphamidon, and Thiodan. Large numbers of this species occurred where DDT, Kepone and Sevin were used and may have reduced yields of potatoes on the Sevin plots. Use of heavy spray machinery on small plots reduced yields.

Systemic Insecticides for Control of Aphids on Field-Grown Easter Lily1

At Harbor, Oregon, season-long protection of field-grown lily plants from aphid attack has been obtained from applications over bulbs in the furrow of granulated phorate and Di-Syston® (O,O -diethyl S -2-(ethylthio)ethyl phosphorodithioate). Mixing granules in the soil before setting the bulbs was also effective, as well as applying carbon dust formulations directly to the bulbs. Soaking bulbs in dilute emulsions or demeton, phorate, or Di-Syston was effective to a lesser degree. Chiefly involved were the foxgrove aphid (Myzus solani (Kitb,)), the melon aphid (Aphis gossypii Glov), and the western lily aphid (Macrosiphum, scoliopi Essig). The shallot aphid (Myzus ascloonicus Doncaster), the potato aphid (Myzas cuphobiae (Thomas)), and the green peach aphid (Myzus persicae (Sulz) appeared in small numbers.

Response of Different Strains of the Green Peach Aphid to Malathion

Several strains of the green peach aphid ( Myzus persicae (Sulz.)), reproducing only parthenogenetically, showed some differences in the amounts of malathion required to kill them. Aphids from Nebraska, Illinois, and Maryland were initially much less tolerant to malathion than aphids from California or Washington. Aphids bred from those surviving treatment showed some increase in tolerance over the original strains, but continued selection did not give further increases. Aphids with wing pads withstood malathion applications better than aphids without wing pads.

Field Evaluation of Demeton in the Control of Beet Yellows Virus

Differences ill yield and/or per cent sugar were found to be associated with the reduction in numbers of green peach aphids ( Myzus persicae (Sulz.)) and delayed incidence of infection of the beet yellows virus in demeton spray-treated plots in three locations in Kern County, California. Populations of aphids were initiated by alatae early in February and were terminated by natural factors during mid-May. Symptoms of virus yellows infection were first found in early April, and spread continued until approximately 100% of the plants were infected. The best available evidence indicated that treatment could delay 100% infection for a period of approximately 3 weeks. With the exception of one field in which generally poor growing conditions prevailed, increased tonnage of beets Vas found in the sprayed plots. Increase in sugar percentage was associated with treatment in all locations.

Further Studies with Systemic Insecticides against the Green Peach Aphid on Potatoes

Tests for the control of the green peach aphid ( Myzus persicae (Sulz.)) on late-crop plantings of potatoes were made at Prosser, Wash. Satisfactory control was either not obtained or, if so, only for 3 to 7 days following applications of several dosages of schradan, demeton, Thimet, Guthion, Am. Cyanamid 12008, Chlorthion, and parathion in 1955, and Diazinon, schradan, and combinations of schradan and Diazinon in 1956 during the period that the numbers of winged migrants present in the area steadily increased. After the peak of aphid migration had been passed and the numbers of winged aphids steadily diminished to the end of the season, many treatments that had previously been unsatisfactory gave good control for 13 to 17 days.

Effect of aphid control on the spread of leafroll in potatoes

Four applications of 10 insecticides were made with a power ground duster to Netted Gem potatoes planted for early and late crops at Yakima, Washington, to determine their relative values for controlling the green peach aphid (Myzus persicae (Sulz.)) and the potato aphid (Macrosiphum solanifolii (Ashm.)) and, indirectly, for preventing the spread of potato leafroll.

Resistance of potato seedling varieties to the natural spread of leaf roll

Potato seedlings were exposed to field spread of leaf roll from adjacent rows in an area where leaf roll spreads consistently year after year. Parents used at first included commercial American and European varieties reputed to be resistant to leaf roll, and a few of the crosses contained some seedlings resistant to the natural spread of leaf roll. When these resistant seedlings were used as parents, the resulting crosses generally were more resistant to field spread than crosses of other kinds. Greater resistance in one of the parents did not always mean greater resistance in the cross. Greater resistance in a cross (on the basis of percentage of seedlings showing any leaf roll) was not necessarily correlated with the percentage of total plants showing leaf roll in the infected seedlings. Field resistance in given seedlings and varieties varied from one season to another on the same farm. Although green peach or spinach aphids (Myzus persicae) probably are an important factor in the field spread of leaf roll, aphid resistance in seedlings is not necessary for field resistance to leaf roll. It is possible to combine field resistance to leaf roll with many characteristics considered commercially desirable in this country.