Showing papers on "Myzus persicae published in 1974"

Rate of Increase of Populations of Cabbage, Green Peach, and Turnip Aphids at Constant Temperatures

Abstract: The maximum finite rate of increase for apterous populations of the cabbage aphid, Brevicoryne brassicae (L.) was 1.14 times per day at 20°C; for the green peach aphid, Myzus persicae (Sulzer), 1.32 times at 25°C; and for the turnip aphid, Hyadaphis pseudobrassicae (Davis), 1.45 times per day at 25°C. The cabbage aphid had the smallest rate of increase at all temperatures, the green peach aphid the greatest rate between 5° and 15 °C, and the turnip aphid the greatest rate between 20° and 30°C. No aphids reproduced at 35°C, only the population of turnip aphids increased at 30°C, and only the population of the green peach aphids increased at 5°C. Other populations decreased at 5° and 30°C. The components of the rate of increase (nymphal development, age-specific survival and fecundity, length of generation, and net reproductive rate) were determined for each aphid at each temperature. Their effect on the rate of increase was examined, as was the age at which 95% of the contribution to the next generation was made. The proportion of each stage in a population with a stable age distribution was also examined. Equations for predicting the rate of increase, and models comparing the relative growth of populations of the three species with time are presented.

Sugar, organic acid, phenolic acid and plant growth regulator content of extracts of honeydew of the aphid Myzus persicae and of its host plant, Raphanus sativus

Abstract: SUMMARY The honeydew of Myzus persicae feeding on radish seedlings contains glucose, fructose, trehalose, melezitose and sucrose, of which glucose and fructose are present in radish seedlings. In addition, the honeydew contains eight organic acids, of which seven are present in uninfested seedlings and six are present in infested radish seedlings: of the eighteen phenolic acids in the honeydew, five are present in uninfested radish seedlings. Auxins, gibberellins, growth inhibitors and cytokinins are present in the honeydew. The presence of carbonate and bicarbonate previously recorded in honeydew of M. persicae could not be confirmed, but ammonia is present in fresh honeydew and accounts for its high pH.

Intraspecific variation of Myzus persicae on sugar beet (Beta vulgaris).

Abstract: SUMMARY Differences in inherited resistance among seven sugar-beet stocks had similar effects on Myzus persicae clones representing the range of variation in aphid response to resistant and susceptible sugar beet observed in fifty-eight clones collected between 1969 and 1971. Three sugar-beet stocks were consistently resistant. Statistically significant interactions between beet stocks and aphid clones did not indicate the existence of biotypes with specific abilities to overcome resistance. M. persicae clones differed in their vigour of colonizing sugar beet, irrespective of the differences between beet stocks. The readiness of adult aphids to settle determined the size of aphid population produced and included a component related to the response of the aphid clone to sugar beet as a host, and a component related to the resistance ranking of the beet stock. Breeding sugar beet with resistance to aphids will be simplified, as the results indicate that, at present, differences between aphid biotypes need not be considered a problem.

Pirimicarb, an Aphicide Nontoxic to Three Entomophagous Arthropods

Abstract: To define the selective toxicity of pirimicarb (5,6-dimethyl-2-dimethylamino-4-pirimidinyl dimethyl carbamate) for use in integrated control, the toxicity of a 50% wettable powder and a fumigant were tested vs. 1 pest and 3 beneficial arthropod species. Although pirimicarb was highly toxic to the green peach aphid ( Myzus persicae (Sulzer)) it was not toxic to Chrysopa carnea Stephens, Encarsia formosa Gahan, and Phytoseiulus persimilis Athias-Henriot. Therefore, pirimicarb could be a particularly useful pesticide in a multipest, integrated control program for greenhouse crop production where aphids, whiteflies and mites coexist.

Aphid-transmitted viruses from lilies in Britain

Abstract: SUMMARY Three aphid-transmitted viruses, tulip breaking, lily symptomless and cucumber mosaic, were obtained from lilies in Britain. Tulip breaking virus was detected by the leaf mottle produced in Lilium formosanum, cucumber mosaic virus by inoculation of sap to Nicotiana clevelandii and Chenopodium quinoa, and lily symptomless virus by electron microscopy of crude leaf extracts from symptomless L. f ormosanum. Lily symptomless virus was transmitted by Myzus persicae, Macrosiphum euphorbiae, Aulacorthum solani and A phis f abae. M. persicae, which in a small experiment appeared a more efficient vector than A.fabae, transmitted the virus in a non-persistent manner. This conflicts with the original report of transmission in a persistent manner by A. gossypii but no transmission by M. persicae. The possibility that there are two distinct viruses with similar pathological effects is discussed. Tulip breaking and lily symptomless viruses spread to bait plants of L. formosanum within a field planting of lilies in Scotland especially during July to Septem­ ber; lily symptomless virus was the more prevalent. No spread of cucumber mosaic virus was detected.

Field studies of potato leaf roll virus spread in south-eastern Scotland, 1962-1969, in relation to aphid populations and other factors.

Abstract: SUMMARY Between 1962 and 1967 spread of potato leaf roll virus (PLRV) and the pattern of potato crop infestation by common potato aphids was investigated at sites in the counties of East Lothian, West Lothian, Midlothian and Berwickshire. Within this area aphid activity and the extent of PLRV spread varied considerably both within years and between years. Macrosiphum euphorbiae activity as measured by the angle of colonization method was as well correlated with PLRV spread as that for Myzus persicae, and in certain years Aulacorthum solani and Aphis fabae may become common enough to have an effect. Spread was not well correlated with site altitude or with distance from the market garden area of Musselburgh, previously thought to be the main regional overwintering centre for aphids. Evidence is presented of the more general distribution of market gardening in the area which may account for these variations. Results from infector units of different sizes and bulk samples suggest, as do earlier findings, that in southern Scotland PLRV spread is mainly from sources within the crop. The practical implications for potato certification in the region are discussed.

Wind effects on spread of watermelon mosaic virus 1 from local virus sources to watermelon.

Abstract: Initial infection with watermelon mosaic virus 1 (WMV-1) and final mosaic incidence in 3 southwest Florida watermelon fields were related to the local distribution of virus-infected weeds and the direction of aphid flights into the fields. Initial virus spread was earlier and more extensive to watermelon downwind from virus sources than to watermelon upwind. The final assessment of mosaic distribution was at first harvest at which time mosaic was concentrated near the local sources of virus. Only Hyadaphis pseudobrassicae (Davis), Tetraneura hirsuta Baker, Rhopalosiphum rufiabdominalis (Sasaki), Aphis gossypii Glover, and Carolinaea rhois Tissot were detected in flights at the time of first virus transmission to watermelon. Although the important WMV-1 vector Myzus persicae (Sulzer) was not detected at the time, initial mosaic incidence in one of the fields was extensive. A. gossypii and H. pseudobrassicae were found capable of transmitting southwest Florida isolates of WMV-l.

Relative feeding rates of Brevicoryne brassicae and Myzus persicae on brussels sprout plants in relation to their susceptibility to systemic insecticides

Abstract: SUMMARY Brevicoryne brassicae and Myzus persicae removed similar quantities of 32P-labelled material from Brussels sprout leaves whether they fed for 24 or 48 h periods. They also removed similar quantities from untreated leaf disks as from leaf disks treated with a sub-lethal dose of menazon. When a lethal dose was used, the uptake of 32P by B. brassicae was significantly less than by M. persicae. M. persicae excreted a greater proportion of 32P label in the honeydew than B. brassicae and a greater proportion of the amount absorbed was lost in the progeny of this aphid than in B. brassicae. B. brassicae was 6.2 times more susceptible than M. persicae to dimethoate acting systemically. When it was applied topically the aphids were equally susceptible. Considerable variation in uptake of 32P occurred between replicates and the factors that could influence this are discussed.

Stability of Green Peach Aphid Resistance in Tuber-bearing Solanum Introductions and Its Effect on Screening Procedures

Abstract: Resistance to green peach aphid (OPA), Myzus persicae (Sulzer), appears to be a relatively stable characteristic in tuber-bearing Solanum species. A high heritability estimate was obtained in replicated field trials over environments and counting dates. Consideration of variance components indicated that multiple evaluations in at least 2 environments with 2 counting dates per environment are desirable for final evaluations of resistance. The number of replications per environment can be reduced to 2 without markedly affecting the heritability estimate or the expected gain in resistance through selection. Results suggest that preliminary screening can be satisfactorily accomplished with one environment and one counting date.

Morphological variation in spring migrants of Myzus persicae (Sulz.) (Hemiptera, Aphididae): comparison of alatae from peach and mangold

Abstract: Spring migrants of Myzus persicae (Sulz.) may be produced either by parthenogenetic aphids derived from fertilised eggs laid on the primary host, or by parthenogenetic aphids overwintering on secondary hosts. Five variates, based1 on eight morphological characters of alate M. persicae, are examined to investigate how to distinguish between alatae derived from populations that have overwintered by these two means. No single variate is adequate to identify correctly all specimens, although two of them, number of abdominal tubercles, and shape of the fenestra in the central abdominal patch, may each correctly assign as many as 90%.

Mammalian Safety of the Aphid-Attacking Fungus Entomophthora nr. thaxteriana

Abstract: A strain of the entomogenous fungus, Entomophthoza nr. thaxteriana (Petch), isolated from the green peach aphid, Myzus persicae (Sulzer) shows promise as a biological control agent for aphids. This isolate is intermediate in its morphology between E. thaxteriana and E. virulenta Hall and Dunn. The spore sizes, i.e. conidia 24 × 19μ, resting spores 22μ, more closely approximate E. virulenta . Lack of rhizoid production, however, has caused us to call this strain E. thaxteriana . The resting spores produced by this isolate can be stored for long periods of time and when properly treated will give up to 98% germination. Greenhouse and field studies have shown this species to be both pathogenic and virulent, giving 100% control in 3 days. The resting spores of this fungus are currently under production in the laboratory and will be field tested against the potato aphid complex in Northern Maine. Effectiveness, however, is not the only criteria which determines an insect pathogen as a good candidate for biological control. It must also be demonstrated that it is safe for man.

Incorporation of thymidine into the chromosomes of aphid (Myzus persicae) embryos

Abstract: Les noyaux somatiques de embryons du puceronMyzus persicae prirent la marque de la thymidine H3 30 min apres son injection dans l'hemocoele maternelle. L'absorption des molecules de cette substance a travers l'epithelium folliculaire et les membranes de l'embryon fut donc tres rapide. Le marquage des metaphses s'est produit apres 90 min. Dans les chromosomesX, l'incorporation fut nettement tardive.

The fate of some organophosphorus compounds applied topically to peach‐potato aphids (Myzus persicae (Sulz.)) resistant and susceptible to insecticides

Abstract: The fate of [14C]-dimethoate and [14C]-parathion after topical application to strains of Myzus persicae resistant and susceptible to organophosphorus compounds was investigated. In 4 h approximately 65% of the dimethoate or para-thion applied was lost from the aphids by evaporation, and this limited the amount available for penetration into the insect. Only approximately 25% of the dose applied penetrated, of which a very small proportion was excreted as metabolites. There was no difference in the amounts penetrating into the resistant and susceptible strains, indicating that penetration was not a factor contributing to the observed resistance. These findings emphasise that evaporation from the cuticle can greatly influence results when insecticides are applied topically.

Latent Period and Retention of Potato Leaf-Roll Virus in its Vector, Myzus persicae

Abstract: Green peach aphids, Myzus persicae Sulz. fed on the Physalis floridana Rydb. plants infected with potato leaf-roll virus (PLRV) for 3 hours, began to transmit the virus 9 hours after leaving the source plants. Aphids injected with extracts or blood from the viruliferous insects were also enable to transmit PLRV 6 hours after injection. The length of the latent period and the frequency of virus transmission in its aphid vector appeared to depend on the virus concentration within the vector. Inoculativity in the transmission of aphids tended gradually to increase till 24 hours after acquisition feeding or injection of extracts and blood from viruliferous insects.PLRV was detected in extracts and blood from aphids fed on the infected P. floridana plants for more than 3 hours, but no virus was recognized in them from insects given an hour's acquisition feeding. Even though the concentration of PLRV in the aphid vectors increased with the prolonged acquisition feeding, it decreased gradually with the time after leaving the source plants. The frequency of virus recovery from blood of the injected aphids also tended similarly to decrease gradually with the time after injection of the virus into aphids.The latent period of PLRV in the aphids vectors appeared to represent the time required for the virus to circulate within the insect body.

The suitability of Megoura viciae(Buckt.) (aphid.) for larvae and adult females of Aphelinus asychis walker (Aphelin.)

Abstract: In the laboratory, the females of the polyphagous aphid parasite Aphelinus asychis accepted vetch aphids (Megoura viciae on Vicia faba) for oviposition and host feeding as readily as peach aphids (Myzus persicae on Brassica oleracea var. gongylodes) of the same size. However, the vetch aphids defended themselves less often; consequently, they were parasitized more frequently.With very few exceptions, all parasite larvae in the vetch aphids died after some days. Blood reactions were scarcely notized. In the peach aphids, development went on normally.After one day with Me. viciae, fecundity of Aphelinus females was reduced during the next day with My. persicae. At room temperature, the average longevity of the adult females was 3.0 days with Me. viciae but 15.2 days with My. persicae. Additional supply with glucose solution extended the life span in both cases.If honeydew from My. persicae (without aphids) or glucose solution was offered to the females they lived for about one month, whereas they died after 3-4 days without any nutrition. With honeydew from Me. viciae they reached a medium life span of 6.7 days. Peach aphids which were cemented each morning to the bottom of the vial for host feeding and (to a lesser degree) oviposition (nearly without honeydew) sustained the life of Aphelinus females for 2 weeks; cemented vetch aphids, however, reduced the longevity significantly when offered alone or in addition to glucose solution or cemented peach aphids.Consequently, Me. viciae is unsuitable not only for the development of the larvae but also for the permanent nutrition of the adult females of A. asychis. This applies to the hemolymph as well as to the honeydew of that species.

Life System Analysis of the Autumn Population of Myzus persicae on Peach Trees

Abstract: The external agencies influencing the size of autumn populations of the green peach aphid, Myzus persicae (Sulzer), were studied. The additive processes that influenced the potential size of the populations were the natality rate, the number of actively reproducing adults, and the number of immigrating reproductives. The reductive processes were predation, emigrating reproductives, leaf fall, and weather. Leaf fall and weather (high winds, low temperatures, and rain) were the major reductive processes that determined whether the population of aphids would attain their potential size. Syrphid larvae were the primary biological control agent, and they were most effective during the peak and decline of the population of aphids. Only about one ovipara per twig survived to lay overwintering eggs from hundreds of immature oviparae found per peach twig.

Necrotic Leaf Spot, A New Virus Disease of Eggplant Caused by Broad Bean Wilt Virus

Abstract: A virus disease of eggplant was found in the vicinity of Tokyo during 1971-1972. Young leaves of the diseased plants showed necrotic spots, sometimes followed by twisting or crinkling of the leaves and dwarfing of whole plant. Some experiments were made to identify the causal virus.The disease was easily transmitted by sap inoculation. Out of 38 species of plants among 15 families, 24 species among 10 families were proved to be susceptible to the causal virus. The virus was also transmitted by the green peach aphid, Myzus persicae (Sulz.).The virus in infective sap was inactivated in 10 minutes at 60-70C, and in 4-6 days at room temperature. Its dilution end point lied between 1:10, 000 and 1:100, 000.Spherical virus particles of about 25nm in diameter were detected in the diseased eggplant leaves under the electron microscope by the direct negative staining method. The same virus particles were also detected in leaves of mechanically inoculated plants.The diseased spinach leaves were ground in phosphate buffer (0.2M, pH 7.6), and then the virus in the extract was partially purified by differential centrifugation followed by sucrose density gradient centrifugation. The finally obtained virus preparation contained a large number of spherical virus particles of about 25nm in diameter. Size and shape of these particles were quite uniform. The preparation showed a high infectivity to Chenopodium amaranticolor.Electron microscopy of the diseased eggplant leaves showed that the virus particles distributed as individuals or as amorphous, sometimes crystalline, aggregates in vacuole and cytoplasm. They were found in epidermal, mesophyll, and also phloem parenchyma cells. Sometimes a chain-like array of the virus particles was observed in plasmodesmata connecting two neighbouring cells. Necrosis and abnormal development of vesicular bodies were common in cells of the diseased tissues.From these results it is evident that the causal virus is broad bean wilt. Broad bean wilt virus has not been reported to occur on eggplant. Thus we propose to name the disease “necrotic leaf spot of eggplant”.

A Survey of the flying Aphid Population at the Alpine Area, Cholla-Pukto

Abstract: This survey was carried out in order to find out population density of aphid at the alpine area. Thetraps were set from May 1 to October 31 in 1973. The summarized results are as follows; 1. About 37 species of aphids were trapped, including 4 species of potatao virus vectors. 2. Of these, dominant species are Aphis gossypii Koch, Aphis lerodendri Matsumura, and Lipahis erysimi Kaltenbaeh. The of 3, dominant species consisted of the trapped total aphids. 3. The potato virus vectors are Myzus persicae Sulzer, Aulacorhum solani Kaltenbach, Lipaphis erysimi Kaltenbaeh and Aphis gossypii Glover. 4. Tile number of aphids and vectors at the alpine area is considerably lower than that at the level land. 5. The peak of the flying aphid occurrence is shown in the latter part of September.

The effect of salivary gland (obtained from myzus persicae sulzer) extract on broad bean epidermal cells infected with bean yellow mosaic virus

Abstract: Experiments were carried out to examine the effect of the extract of the salivary gland of Myzus persicae Sulzer on broad bean epidermal cells infected with bean yellow mosaic virus (BYMV). The extract had been obtained by homogenizing the organ in distilled water.The extract of the salivary gland had an effect of producing microscopic changes in healthy and diseased epidermal cells. This effect was severer against virus-infected cells than non-infected cells. The most remarkable change in infected cells was the appearance of plasmolysis. This plasmolytic activity of the salivary gland extract was not destroyed by heat treatment.Virus inclusions in infected cells were granulated and diffused by the action of the extract. The cells plasmolyzed by the extract were different in shape from those plasmolyzed with 0.8M sucrose solution or 0 8M KNO3 solution. There was no significant difference in plasmolysis induced with the sucrose solution between healthy and diseased cells. The salivary gland extract was therefore presumed to act on virus-infected cells in a specific manner.The extracts of intestine, stomach, brain, and oesophageal ganglion caused mild plasmolysis of infected cells. They were, however, much weaker in plasmolytic activity than the salivary gland extract. Moreover, when exposed to this extract, the infected epidermal tissue decreased in virus activity.These results suggest that the saliva may play an important role on the transmission of the virus by the aphid; that is, by the influence of the saliva on infected cells, it may be difficult for the aphid stylet to acquire virus particles from these cells. The extent of the salivary effect would be determined by the interaction between the saliva and the plant cell. Therefore, the action of the saliva is presumed to be the cause of the low transmission of BYMV by aphid feeding.

BYMV-罹病ソラマメ葉表皮細胞に及ぼすモモアカアブラムシ ( Myzus persicae Sulzer) の唾液腺磨砕液の影響

Abstract: Experiments were carried out to examine the effect of the extract of the salivary gland of Myzus persicae Sulzer on broad bean epidermal cells infected with bean yellow mosaic virus (BYMV). The extract had been obtained by homogenizing the organ in distilled water.The extract of the salivary gland had an effect of producing microscopic changes in healthy and diseased epidermal cells. This effect was severer against virus-infected cells than non-infected cells. The most remarkable change in infected cells was the appearance of plasmolysis. This plasmolytic activity of the salivary gland extract was not destroyed by heat treatment.Virus inclusions in infected cells were granulated and diffused by the action of the extract. The cells plasmolyzed by the extract were different in shape from those plasmolyzed with 0.8M sucrose solution or 0 8M KNO3 solution. There was no significant difference in plasmolysis induced with the sucrose solution between healthy and diseased cells. The salivary gland extract was therefore presumed to act on virus-infected cells in a specific manner.The extracts of intestine, stomach, brain, and oesophageal ganglion caused mild plasmolysis of infected cells. They were, however, much weaker in plasmolytic activity than the salivary gland extract. Moreover, when exposed to this extract, the infected epidermal tissue decreased in virus activity.These results suggest that the saliva may play an important role on the transmission of the virus by the aphid; that is, by the influence of the saliva on infected cells, it may be difficult for the aphid stylet to acquire virus particles from these cells. The extent of the salivary effect would be determined by the interaction between the saliva and the plant cell. Therefore, the action of the saliva is presumed to be the cause of the low transmission of BYMV by aphid feeding.