The distribution and movement of apterous Myzus persicae on rapidly growing turnip plants

Abstract. 1. The spatial distribution of both adult apterous and nymphal M.persicae was related to the "age" of the leaf.
2. This distribution was bimodal and was maintained even on rapidly "ageing" leaves by frequent emigration.
3. The spatial distribution was also found to change between regions of a leaf, the densest populations occurring at the base of all leaves, but with the populations most evenly distributed on the young and old leaves.
4. The spatial distribution also changed during the nymphal period, the youngest nymphs being found predominantly on the lamina, the fourth instar and adults on the largest available veins.
5. On rapidly growing plants, individual M.persicae may move to a new feeding site as frequently as every 24–48 h.
6. Some of the causes and consequences of this frequent dispersal are discussed.     

The effect of leaf excision on the performance of Myzus persicae and Brevicoryne brassicae in relation to the nutrient treatment of the plants

Two groups of brussels sprout plants of one variety given different fertilizer treatments proved ‘resistant’ and ‘susceptible’ to both Myzus persicae and Breicoryrie brassicae, as measured by aphid mean relative growth rate. The hypothesis that leaf disc would fail to reflect differences in ‘nutritionallybased’ plant resistance was confirmed with B.brussicue but not M.persicae. Both aphids grew more slowly on discs than leaves of ‘susceptible’ plants; the reverse tendency showed on ‘resistant’ material. Total:(, amino nitrogen proved poorly correlated with aphid performance. Previously published (van Emden & Bashford, 1971) equations relating individual amino acids to aphid performance gave a better fit to the results, but still failed to account for the reduced performance of the aphids on ‘susceptible’ discs.     

无翅桃蚜对龟纹瓢虫的视觉和嗅觉识别反应

为探明桃蚜Myzus persicae是否可以识别来自其捕食性天敌的嗅觉和视觉信息,本研究采用桃蚜和龟纹瓢虫Propylaea japonica这一猎物-捕食者系统,在室内测定了无翅桃蚜对龟纹瓢虫成虫体色和挥发物的识别反应。选择反应试验结果表明,无翅桃蚜既能通过视觉信息识别瓢虫的存在,也能通过嗅觉信息识别瓢虫的存在,说明桃蚜对龟纹瓢虫体色和气味信息的识别存在一定的冗余现象。剂量反应试验结果表明,龟纹瓢虫粗提物的剂量与其对桃蚜的驱避率呈现良好的线性关系,识别反应剂量的临界值在0.3~0.6个瓢虫当量之间,1.2~1.5个瓢虫当量的粗提物的驱避作用与20头活体龟纹瓢虫的驱避作用相当。结论认为,桃蚜可以识别龟纹瓢虫的存在,并对其作出一定的躲避反应,从而降低被捕食的风险。     

Effects of aluminum mulch on fecundity of apterous Myzus persicae on head lettuce in a field planting

Head lettuce field plantings were artificially infested with apterous adults of the green peach aphid, Myzus persicae (Sulzer). Significantly greater aphid fecundity was demonstrated on plants grown through aluminum-coated construction paper than on plants grown on bare soil. Higher temperatures and host-plant physiology were factors modified by the mulch, and could have resulted in larger aphid populations on plants grown over a reflective surface as the season progressed. Faster plant growth and a significantly larger yield per head of lettuce also resulted from the use of the aluminum mulch. The incidence of a leafhopper-borne plant disease, aster yellows, was significantly reduced on head lettuce in the aluminum mulch plots.

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Résumé Des cultures de laitue ont été artificiellement contaminées avec des adultes aptères de Myzus persicae. La fécondité a été significativement augmentée sur les plantes poussant sur un sol recouvert par un voile d'aluminium, comparées à celles poussant sur un sol nu. Cette augmentation pourrait entrainer des populations de pucerons de plus en plus importantes, au fur et à mesure de l'avancement de la saison, sur les plantes poussant au dessus d'une surface fortement réfléchissante. L'utilisation du voile d'aluminium a provoqué simultanément une accélération de la croissance et une augmentation des rendements de laitue. Ces résultats semblent dus à une augmentation de la température diurne, à une meilleure conservation de l'humidité et à une plus forte réflexion de la lumière lorsqu'il y a présence de voile d'aluminium. Par aulleurs, les dégâts provoqués sur feuilles par les germes pathogénes transmis par les Cicadelles delles sont significativement plus rares sur sol couvert de voile d'aluminium.

     

Feeding studies on gynoparae, males and apterous virginoparae of Myzus persicae on potato by electrical penetration graph

Abstract:  Feeding behaviour of parthenogenetic apterae, post-teneral gynoparae and males of a holocyclic parthenogenetic lineage of Myzus persicae (Sulzer) (Hem., Aphididae) was studied on potato plants, Solanum tuberosum L. (Solanaceae) by DC-electrical penetration graph recording. Differences were observed between morphs during the 7-h recordings, specifically in the first phase of subcuticular probing and in xylem and phloem-related activities. The time required for the first penetration and first cell puncture of the non-vascular tissues was shorter in apterae than in gynoparae and males. Apterae more often showed phloem activities and sustained sap ingestion (100%) than winged morphs ( ca. 25%). In addition, phloem ingestion was much longer in apterae than in winged morphs, 3458 s and 25–70 s respectively. In contrast, winged morphs spent 14–21% of the available time ingesting sap from xylem while in apterae xylem sap uptake was only for 2% of the time. Furthermore, the data showed that males perform in general all the feeding behaviours that other conspecific morphs exhibit. The differences in feeding behaviour among morphs of M. persicae are discussed in relation to host specialization and to their possible involvement in non-persistent transmission of viruses.     

The performance of Brevicoryne brassicae and Myzus persicae in relation to plant age and leaf amino acids

With increasing plant age, total soluble nitrogen of Brussels sprout plants decreased after a peak at 6–9 weeks. The plants then became less suitable for Brevicoryne brassicae and Myzus persicae (particularly the latter) as shown by estimates of the mean relative growth rate (RGR) of the aphids in two experiments. This growth statistic was, however, only poorly correlated with total soluble N and this lack of correlation was particularly marked on plants less than 9 weeks old. Multiple regression on the leaf amino acid spectrum indicated that much of the variability in aphid RGR could be assigned to relatively few amino acids. The complex of asparagine and glutamine gave a positive coefficient for both aphids, but otherwise different amino acids were involved in the regression for each aphid. Attention is drawn to the presence in each regression of an amino acid with a negative coefficient; the inverse correlation of M. persicae RGR with amino-butyric acid may be particularly important in the aphid/hostplant relationship.

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Zusammenfassung In einem ersten Versuch zeigte sich, daß der Gehalt an löslichem Stickstoff in den Blättern mit dem Alter der Pflanzen zwischen 8 und 20 Wochen ständig abnahm. Die relative Wachstumsrate (RGR) von Brevicoryne brassicae veränderte sich dabei kaum, jedoch waren die einzelnen Werte der RGR und des löslichen Stickstoffgehalts der entsprechenden Pflanzen gut korreliert. Dagegen reagierte Myzus persicae unmittelbarer auf das Pflanzenalter als auf den Stickstoffgehalt und ihre RGR nahm ab, je älter die Pflanzen wurden.Im zweiten Versuch wurden jüngere Pflanzen benützt. Hier stieg der Gehalt an löslichem Stickstoff bis zu einem Höhepunkt in der neunten Woche an. Unabhängig vom Stickstoffgehalt nahm die RGR bei M. persicae wieder ab, je älter die Pflanzen wurden. In diesem Versuch wurde auch der, Aminosäuregehalt der Blätter analysiert. Die Variabilität der RGR beider Blattlausarten war mit 4 Aminosäuren korreliert. Sowohl Asparagin wie Glutamin zusammen waren dabei für beide Blattlausarten wichtig; daneben erschienen Threonin und Phenylalanin in der Korrelationsgleichung für B. brassicae, Methionin und Aminobuttersäure in der für M. persicae. Für M. persicae konnten so 42% der gesamten Variabilität der RGR durch die Korrelationsgleichung erklärt werden; für B. brassicae nur 21%.Von besonderem Interesse ist 1) daß sich 42% der M. persicae-Variabilität mit der Verfügbarkeit von nur 4 Aminosäuren erklären lassen, 2) daß die Korrelation zwischen Blattlaus-Wachstumsrate und Asparagin + Glutamin vielleicht dem oft nachgewiesenen Zusammenhang zwischen Pflanzenempfindlichkeit und löslichem Stickstoff entspricht, 3) daß die Wachstumsraten der beiden Blattlausarten negativ mit je einer Aminosäure korreliert sind: mit Phenylalanin bei B. brassicae und, sehr wichtig, mit Aminobuttersäure bei M. persicae und 4) daß die Resultate bezüglich M. persicae ziemlich gut mit Resultaten bei küstlichen Ernährungsversuchen anderer Autoren übereinstimmen.

     

Nitrogen fertility and leaf age effect on ethylene production of cotton in a controlled environment

The effect of nitrogen (N) fertility and its subsequent impact on ethylene production varies with plant species. Additionally, ethylene production reportedly increases or decreases with leaf age for several species. We examined leaf age and N fertility effects on ethylene production of cotton (Gossypium hirsutum L.) during the early vegetative stages of development (14 to 42 days after emergence) in a controlled environment. Ethylene production was determined by sampling leaf discs from the topmost fully expanded, middle, and bottom leaves of the canopy at 14, 21, 28, 35, and 42 days after emergence. Ethylene was collected from leaf discs in sealed test tubes and quantified by gas chromatography. Early in development, a N deficiency was associated with elevated levels of ethylene, suggesting stress ethylene production was occurring in response to a N-deficiency stress. As plant development progressed, however, increased ethylene production was associated with higher levels of applied N. Additionally, higher ethylene production was linearly associated with higher chlorophyll levels in all three leaves sampled. Ethylene production within plants receiving any given rate of N initially increased and then decreased with leaf age. The dynamics of this relationship suggest that as the N status of the plant changes during plant development, the relative rate of ethylene production, with regard to leaf age, is significantly influenced.     

The effect of plant age and infection with virus yellows on the survival of Myzus persicae on sugar beet

Survival of Myzus persicae confined in clip-cages on mature leaves of sugar beet declined as the plants aged. Death of aphids was often preceded by the appearance of a black deposit in the aphids' stomachs, which may have been the cause of death. Both the rate of death and the proportion of aphids dying with black deposits was significantly less when plants were infected with beet yellows virus or beet mild yellowing virus, by comparison with healthy plants. The implication of these phenomena on the onset of mature plant resistance is discussed.     

基于微卫星标记的桃蚜种群寄主遗传分化

桃蚜Myzus persicae(Sulzer)是寄主范围最广、危害最大的蚜虫种类之一。为了探明桃蚜在不同寄主上的遗传分化特点,采用微卫星分子标记技术,对西兰花、桃树、辣椒上的桃蚜种群进行遗传多样性和遗传结构研究。结果表明,在所选用的5个微卫星位点上共检测到38个等位基因,平均每个位点的等位基因数达到7.6个,桃树种群遗传多样性最高,这可能是因为各种夏寄主上的桃蚜迁回桃树上越冬,从而使多种等位基因和基因型得以聚集的原因。等位基因频率差异分析显示西兰花种群、桃树种群和辣椒种群两两之间(除了桃树06种群和辣椒06种群之间没有遗传分化外)都出现了明显遗传分化,相比之下桃树种群和辣椒种群的分化程度要比桃树种群和西兰花种群的分化程度低,这可能预示着西兰花寄主上的桃蚜正在向远离桃树和辣椒种群的方向进化。     

Responses of Myzus persicae and Brevicoryne brassicae to leaf age and water stress in Brussels sprouts grown in pots

Although intermittent water stress is largely beneficial and continuous water stress largely detrimental to the reproduction and survival of Myzus persicae and Brevicoryne brassicae feeding on Brussels sprouts, there are differences between the species on different leaf ages. During intermittent water stress in the old leaves, the normal feeding stratum of M. persicae, this aphid is relatively more successful than B. brassicae. During continuous water stress in the young leaves, the normal feeding stratum of B. brassicae, this aphid is relatively more successful than M. persicae. The high suitability of old leaves for M. persicae and, to a lesser extent, their low suitability for B. brassicae, are also apparent on turgid plants, in terms of reproduction, survival and the proportion of alate progeny. For M. persicae substrates which permit greater reproduction also promote fewer alatae but this is not always so for B. brassicae. However, crowding was not controlled in these experiments.It is suggested that these responses result from variation in the provision of the different nutritional and phagostimulant requirements of the two species by different leaf ages and during water stress.In the field irrigation may delay aphid multiplication during dry weather.

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Zusammenfassung Die Reaktionen ungeflügelter Virginoparer von M. persicae und B. brassicae auf verschiedenes Blattalter von Kohlpflanzen (Brassicae oleracea L. var. bullata gemmifera) in Blumentöpfen mit verschiedener Wasserversorgung wurde an der Reproduktionsrate, der Entwicklungs-und Lebensdauer (des Adultstadiums, der Dauer der reproduktiven wie der post-reproduktiven Phase) und der Geflügeltenbildung der Blattläuse untersucht. Dazu wurden zwei Formen des Wassermangels benutzt: (1) vorübergehender, bei welchem das verfügbare (AW) zwischen der Feldkapazität und einen im voraus festgelegten Defizit (10% = Wasser feucht, 50% = mäßig, 90% = trocken) schwankte, und (2) dauernder, bei welchem eine Abnahme des verfügbaren Wässers von einem bekannten Ausgangspunkt allmählich erfolgte.Obwohl für die Aphiden vorübergehender Wassermangel weitgehend vorteilhaft, beständiger aber schädlich ist, bestehen Unterschiede zwischen den Arten auf verschiedenaltrigen Blättern. Auf jungem und reifem Laub steigen Vermehrung und Lebensdauer beider Arten Durch vorübergehenden Wassermangel an, aber auf alten Blättern leidet B. brassicae in dem Maße wie sich der Mangel verstärkt, während M. persicae bei mäßigem Mangel Vorteile hat und nur leidet, wenn periodisches Welken eintritt. Bei beiden Arten verursacht beständiger Wassermangel Hemmung der Reproduktion. Diese Abnahme beschleunigt sich bei Annäherung an den permanenten Welkepunkt (PWP) und war für die Aphiden auf alten Blättern am stärksten. Im Gegensatz zu M. persicae nimmt die Reproduktionsrate von B. brassicae sogar am permanenten Welkepunkt nicht ab. Die. hohe Eignung alter Blätter für M. persicae und — in geringerem Maße — ihre geringe Eignung für B. brassicae waren auch an turgeszenten Pflanzen bei der Reproduktionsrate, der Überlebensdauer und dem Prozentsatz geflügelter Nachkommen deutlich festzustellen.Es wird vermutet, daß sich diese Reaktionen aus Verschiedenheiten in der Befriedigung unterschiedlicher nutritiver und phagostimulatorischer Bedürfnisse der beiden Arten auf verschieden alten Blättern und bei Wassermangel ergeben. Im Freien dürfte bei trockenem Wetter künstliche Bewässerung die Blattlausvermehrung verzögern.

     

Reproduction of the aphid Myzus persicae related to the mineral nutrition of potato plants

The fecundity and reproduction rate of caged Myzus persicae on leaves of potato plants growing on nutrient solutions with different anion and cation ratios were measured. The levels of total and soluble N in the leaves and the reproduction rate were found to be positively correlated with the amounts of N in the nutrient solutions. Longevity and reproduction rate were considerably less on 4-week-old plants than on 8-week-old plants; this difference is not correlated with the total N or soluble N-content of the leaves. When comparing aphid development on plants, daily variations in the amounts of N compounds in the leaves could provoke an erroneous basis for assessing the physiological condition of the host plant.

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Résumé Des pucerons Myzus persicae sont élevés individuellement dans des cages sur des feuilles de pommes de terre. Chaque expérience comporte deux groupes de plantes les unes âgées d'un mois, les autres de deux mois. Les plantes sont alimentées avec des solutions nutritives dans lesquelles le rapport d'anions ou cations est différent, mais qui demeurent ioniquement équilibrées.La reproduction de Myzus persicae, sur les plantes du même âge, montre une corrélation avec la quantité de N dans la solution nutritive et avec la teneur des feuilles en N total ou en N soluble.Le taux reproduction sur des plantes âgées de deux mois est en moyenne plus élevé que sur les plantes âgées d'un mois. Cette différence n'est pas en corrélation avec la teneur des feuilles en N total ou N soluble.Sur des plantes âgées de deux mois le nombre de jours productifs par femelle est plus élevé que sur des plantes âgées d'un mois.La teneur des feuilles en composés azotés peut montrer des fluctuations quotidiennes importantes; pendant la durée de l'expérience un échantillonnage fréquent est indispensable à l'obtention de données reproductibles.Le rapport de K/Mg dans les solutions nutritives n'a pas une influence significative sur la fécondité des pucerons.La teneur en eau des feuilles n'est pas influencée par les différentes solutions nutritives ni par l'âge de la plante.Si on permet aux pucerons de se développer librement sur les plantes, on constate que la densité de population est la même sur les différentes solutions nutritives. La nutrition minérale n'influence pas de façon significative les pourcentages de production d'insectes ailés.

     

The effect of artificial diet on the production of alarm pheromone by Myzus persicae

The cornicle secretion of Myzus persicae reared on artificial diet only elicits an alarm response in plant‐reared conspecifics after the young aphids have been transferred to plants for 7 days. Acetate in the form of 0.32% sodium acetate has been added to the diet as an early step in synthesis of the alarm pheromone, (E)‐β‐farnesene (EBF). The cornicle secretion of diet‐reared aphids then elicits an alarm response. However, there is no difference in internal EBF concentration between plant‐ and diet‐reared aphids. Puncturing aphids, either plant‐ or diet‐reared, with a pin shows that both can elicit an alarm response, whereas it is reduced by half with diet‐reared individuals. Although there is no significant difference in the concentration of EBF produced, the total amount in diet‐reared aphids is increased by acetate in the diet to a level similar to that in plant‐reared individuals: the size of aphids reared on an acetate‐supplemented diet is increased and comparable with the size of those that are plant‐reared. Bioassays with a range of EBF concentrations show a high threshold for the alarm response. It is concluded that the different size of aphids reared on plants and standard diet results in them secreting, respectively, above and below the response threshold.     

Effect of colour and shape of ‘target’ hosts on the orientation of emigrating adult apterous Myzus persicae in the laboratory

The orientation response of adult apterous Myzus persicae (Sulz.) to targets approximately 1 m distant in an arena was investigated. The targets were combinations of turnip leaves of different known ages and/or paper leaves of the same shape and size, but of different known reflectances. In white arenas, the apterae consistently approached the target which had the greatest percentage reflectance in the range 520–580 nm over targets of lesser reflectance. There was no evidence of olfaction. Compact shapes were approached more frequently than narrow rectangles of the same surface area. Turnip leaves against a black background were approached less frequently than those against a white background. Small black targets against a white background elicited a response, although most apterae became disorientated before reaching them. With increasing target size, this disorientation occurred at increasing distances. These responses to colour and shape are similar to those described by other authors for flight exhausted alatae.

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Effets de la couleur et de la forme des hôtes cibles sur l'orientation au laboratoire d'adultes aptères Myzus persicae en train d'émigrer

Résumé L'étude a porté sur la ré-orientation de l'adulte aptère Myzus persicae en réaction à des cibles situées approximativement à 1 m de distance dans une arène blanche. Les cibles étaient composées de feuilles de navet de différents âges connus et/ou de feuilles de papier de la même taille et même forme, mais de réflectance différente mais connue. Dans des arènes blanches, les adultes aptères ont atteint d'une façon nette les cibles, qui avaient la plus grande réflectance dans la gamme de 520–580 nm. Il n'y avait pas d'indices d'olfaction. Les formes compactes ont été atteintes plus fréquemment que les rectangles étroits de même superficie. Les feuilles de navet sur fond noir étaient atteintes moins fréquemment que celles qui étaient sur un fond blanc. De petites cibles noires sur fond blanc ont provoqué une certaine réaction, bienque la plupart des adultes aptères semblaient devenir désorientées avant de les atteindre. En augmentant la taille de la cible, cette désorientation est apparue à des distances croissantes. Ces réactions à la couleur et à la forme correspondent à celles décrites par d'autres auteurs chez des adultes ailés épuisés par leur vol.

     

Feeding and the uptake of phosphamidon by two strains of Myzus persicae (Sulz.) on radish plants

Intraspecific differences in the uptake of solutions containing phosphamidon, enclosed in Parafilm membranes, have previously been demonstrated in Myzus persicue. This paper shows that similar differences also occur when the aphids are fed on treated plants. Uptake from phosphamidon-contaminated plants is reduced though the effect was quantitatively different in the two strains of aphid studied. The depression in the level of feeding was related to the concentration of insecticide applied to the plant.     

UV-B照射对烟蚜抗氧化系统的影响

为明确UV-B照射能否对烟蚜Myzus persicae造成氧化胁迫以及烟蚜酶促抗氧化系统在UV照射下的应答反应,本研究采用比色法,测定了UV-B照射不同时间(0、15、30和45 min)后,烟蚜体内的总抗氧化能力、丙二醛(MDA)和蛋白质羰基含量,及其体内超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、过氧化物酶(POD)和谷胱甘肽-S-转移酶(GST)的活性。与对照相比,UV-B照射时间为15和30 min时,烟蚜体内的总抗氧化能力、丙二醛和蛋白羰基含量显著升高,当照射时间延长至45 min时,均又恢复到对照水平。UV-B照射烟蚜15 min时,其体内CAT、POD和GST活性均显著升高;照射时间延长至30 min时,SOD活性、CAT和POD活性达到最大值,GST活性恢复到对照水平。当照射时间延长至45 min时,SOD、CAT、POD和GST的活性均恢复到对照水平。本研究表明UV-B照射对烟蚜造成氧化胁迫,使得烟蚜体内酶促抗氧化系统产生应激响应。     

寄主植物对烟蚜药剂敏感性及相关酶活性的影响

以甘蓝、烟草和桃树上的饲养的烟蚜Myzus persicae（Sulzer）种群为研究材料,分别测试了其对吡虫啉、丁硫克百威和氰戊菊酯这3种杀虫剂的敏感性。结果表明,桃树上的烟蚜种群敏感性最高,其次为烟草种群,甘蓝种群最低。测试了在3种不同寄主上饲养的烟蚜种群的羧酸酯酶、乙酰胆碱酯酶和谷光甘肽-s-转移酶的比活力,这3种酶均表现为甘蓝种群最高,其次为烟草种群,桃树种群最低。     

Efficacy of pymetrozine against Myzus persicae and in reducing potato virus Y transmission on tobacco plants

Forty‐four parthenogenetic lineages of Myzus persicae s.l. (Sulzer) from tobacco crops and peach orchards located in various regions of Greece were examined to determine their response to the insecticide pymetrozine using leaf‐dip bio‐assays. The results show that the aphid has not developed resistance, as all lineages exhibited resistance factors bellow 6.0. In transmission experiments of potato virus Y (PVY) using a lineage of the tobacco‐adapted subspecies M. persicae nicotianae Blackman on tobacco plants, one foliar application with pymetrozine provided adequate protection for 7 days. Pymetrozine significantly reduced both virus acquisition and inoculation compared with the untreated control and the reduction was comparable to a mineral oil application. These results are discussed in terms of the advantage of incorporating pymetrozine as a compound of pest management strategies against M. persicae s.l. and for control of non‐persistent viruses, especially in crops such as tobacco because of the high selection pressure from neonicotinoids resulting in potential of resistance developing in aphid populations.     

几种药剂对烟蚜毒力的温度效应

在15℃、20℃、25℃、30℃及35℃条件下分别测定了吡虫啉、丁硫克百威和氰戊菊酯对烟蚜毒力的温度效应。结果显示，吡虫啉和丁硫克百威对烟蚜的毒力呈正温度效应，但随着温度上升，烟蚜对吡虫啉的敏感性变化比丁硫克百威大。毗虫啉毒力在35℃时为15℃时的7．12倍；而丁硫克百威为2．88倍。氰戊菊酯对烟蚜的毒力呈负温度效应，在35℃时的毒力约为15℃时的1／5。鉴于这些药剂的毒力受温度影响的规律，建议在气温较低时选用氰戊菊酯等负温度效应的农药，在气温较高时则选用吡虫啉等正温度效应的农药，以充分发挥农药的性能，减少农药使用量、降低防治成本。