•The apple aphids Aphis pomi and Aphis spiraecola are often tended by Lasius niger ants in European apple orchards.•Sugar dispensers (bottles and agar cubes) reduced the number of L. niger workers ...tending aphid colonies compared to controls.•Reduced ant attendance increased the activity of aphidophagous predators and decreased apple aphid populations.•Bottle dispensers produced more consistent benefits over two study years compared to agar cubes.
The green apple aphids Aphis pomi DeGeer and A. spiraecola Patch are serious pests of apple, especially in young orchards, where both species establish facultative mutualisms with ants. This study, conducted in Hungary in 2014 and 2015, manipulated the presence of the common black ant Lasius niger (L.) on colonies of Aphis spp. in apple tree canopies. To this end, two kinds of sugar dispensers (bottle dispensers and agar jelly cubes), each providing a sucrose solution with 300 g/1000 ml concentration, were deployed as alternative sugar sources for the ants, with plots lacking dispensers serving as controls. Both forms of sugar provisioning reduced the number of ants tending Aphis spp. colonies and reduced aphid populations compared to controls in both years. However, bottle dispensers demonstrated consistent efficacy in both years, whereas agar jelly cubes were less reliable in distracting the ants. Both treatments significantly increased the abundance of natural enemies at Aphis spp. colonies compared to controls. Our results indicate that the provisioning of ants with sugar in apple orchards can effectively disrupt ant-aphid mutualisms in the case of Aphis spp., by drawing ants away from aphid colonies and thus increasing natural enemy predation on aphid colonies. The use of sugar-feeding tactics to alter ant behaviour should permit reduced pesticide use in apple orchards, whether to control aphids or other pests that might serve as prey for ants, and is fundamentally compatible with biological pest control in apple orchards.
One of the key reasons for the poor performance of natural enemies of honeydew-producing insect pests is mutualism between ants and some aphid species. The findings demonstrated that red wood ant,
...Linnaeus (Hymenoptera: Formicidae) had a deleterious impact on different biological parameters of the lady beetle,
Goeze (Coleoptera: Coccinellidae).
laid far fewer eggs in ant-tended aphid colonies, laying nearly 2.5 times more eggs in ant absence. Ants antennated and bit the lady beetle eggs, resulting in significantly low egg hatching of 66 per cent over 85 per cent in ant absent treatments. The presence of ants significantly reduced the development of all larval instars. The highest reduction was found in the fourth larval instar (31.33% reduction), and the lowest in the first larval instar (20% reduction). Later larval instars were more aggressively attacked by ants than earlier instars. The first and second larval instars stopped their feeding and movement in response to ant aggression. The third and fourth larval instars modified their mobility, resulting in increased ant aggression towards them. Adult lady beetles were shown to be more vulnerable to ant attacks than larvae. However,
adults demonstrated counterattacks in the form of diverse defensive reaction behaviours in response to
aggression.
The coarse spray air-induction nozzles have documented pesticide drift reducing potential and hence pose lower risk of environmental pollution than the standard fine spray hollow cone nozzles. ...However, it is questioned that use of the low-drift nozzles might not provide as effective crop protection as the standard nozzles. The objective of work was to assess the pest and disease control efficacy as affected by spray volume rate and nozzle type. The experiment was carried out in apple orchard, cv Jonagold/M26. The evaluated treatments were combinations of three spray volume rates: 250, 500 and 750lha−1, and two types of nozzles: hollow cone nozzles generating very fine spray, and flat fan air induction nozzles producing coarse droplets. The biological performance of treatments was determined based on severity of diseases: apple scab (Venturia inaequalis), powdery mildew (Podosphaera leucotricha) and bull's eye rot (Pezicula spp.), as well as population or damage caused by pests: green apple aphid (Aphis pomi), rosy apple aphid (Dysaphis plantaginea Pass.), woolly apple aphid (Eriosoma lanigerum), apple rust mite (Aculus schlechtendali) and apple blossom weevil (Anthonomus pomorum L.). In general apple scab was equally controlled by all treatments. Only in the years of high infection pressure efficacy of powdery mildew control was better for fine spray nozzles and high volume rates. Green and rosy apple aphids were better controlled with higher volume rates, though significance of the advantage over the lower rates was occasional. No effect of spray quality on efficacy of aphid and mite control was found for any spray volume rate. Better control of apple blossom weevil and woolly apple aphid was achieved with the high spray volume rate providing heavy coverage to the point of run-off. The air induction nozzles having drift reducing potential are biologically efficacious alternative to conventional hollow cone nozzles.
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•Low-drift nozzles used for pesticide application pose low risk of environmental pollution.•Biological effect of crop protection obtained by low-drift nozzles is still questioned.•Efficacy of pest and disease control for standard and low-drift nozzles assessed in apples.•No explicit effect of nozzle type on pests and disease control efficacy.•Low-drift air induction nozzles can be efficacious alternative to standards nozzles.
The Asian ladybeetle Harmonia axyridis Pallas is an invasive species commonly found in Canadian apple orchards. It threatens native ladybeetles through exploitative competition and intraguild ...predation (IGP), including the 12 spotted ladybeetle Coleomegilla maculata DeGeer (Gagnon, Heimpel and Brodeur, 2011). Both species are exposed to novaluron, a reduced risk insecticide used against the codling moth Cydia pomonella (L.), the primary pest in apple orchards. Previous research showed that novaluron is highly toxic for the invasive H. axyridis, but it is less toxic for the indigenous C. maculata. Novaluron reduces the adaptive value of IGP for H. axyridis but not for C. maculata. However, there is a lack of knowledge on the combined effect of novaluron and IGP outside laboratory conditions. This study explores under semi‐field conditions the effect of novaluron residues and IGP on the survival of H. axyridis and C. maculata larvae. IGP was assessed considering third instar larvae as predators. Results showed that novaluron was toxic for first instar larvae of both species after 10 days of exposure. When H. axyridis was the intraguild predator, novaluron increased the survival of the intraguild preys. Novaluron did not change the outcome of the IGP when C. maculata was the intraguild predator. These results indicate that novaluron can change the competition outcome between the invasive H. axyridis and a native ladybeetle species. This is the first demonstration that intraguild predation and competition may be greatly altered in the presence of pesticides.
Herbivore insects have strong impacts on leaf gas exchange when feeding on the plant. Leaf age also drives leaf gas exchanges but the interaction of leaf age and phloem herbivory has been largely ...underexplored. We investigated the amplitude and direction of herbivore impact on leaf gas exchange across a wide range of leaf age in the apple tree–apple green aphid (
Aphis pomi
) system. We measured the gas exchange (assimilation and transpiration rates, stomatal conductance and internal CO
2
concentration) of leaves infested versus non-infested by the aphid across leaf age. For very young leaves up to 15 days-old, the gas exchange rates of infested leaves were similar to those of non-infested leaves. After few days, photosynthesis, stomatal conductance and transpiration rate increased in infested leaves up to about the age of 30 days, and gradually decreased after that age. By contrast, gas exchanges in non-infested leaves gradually decreased across leaf age such that they were always lower than in infested leaves. Aphids were observed on relatively young leaves up to 25 days and despite the positive effect on leaf photosynthesis and leaf performance, their presence negatively affected the growth rate of apple seedlings. Indeed, aphids decreased leaf dry mass, leaf surface, and leaf carbon content except in old leaves. By contrast, aphids induced an increase in leaf nitrogen content and the deviation relative to non-infested leaves increased with leaf age. Overall, the impacts of aphids at multiple levels of plant performance depend on leaf age. While aphids cause an increase in some leaf traits (gas exchanges and nitrogen content), they also depress others (plant growth rate and carbon content). The balance between those effects, as modulated by leaf age, may be the key for herbivory mitigation in plants.
Upon damage by herbivores, plants release herbivory-induced plant volatiles (HIPVs). To find their prey, the pest’s natural enemies need to be fine-tuned to the composition of these volatiles. ...Whereas standard methods can be used in the identification and quantitation of HIPVs, more recently introduced techniques such as PTR-ToF–MS provide temporal patterns of the volatile release and detect additional compounds. In this study, we compared the volatile profile of apple trees infested with two aphid species, the green apple aphid
Aphis pomi
, and the rosy apple aphid
Dysaphis plantaginea
, by CLSA-GC–MS complemented by PTR-ToF–MS. Compounds commonly released in conjunction with both species include nonanal, decanal, methyl salicylate, geranyl acetone, (
Z
)-3-hexenyl acetate, (
Z
)-3-hexenyl butanoate, (
Z
)-3-hexenyl 2-methyl-butanoate, (
E
)-β-caryophyllene, β-bourbonene and (
Z
)-3-hexenyl benzoate. In addition, benzaldehyde and (
E
)-β-farnesene were exclusively associated with
A. pomi
, whereas linalool, (
E)
-4,8-dimethyl-1,3,7-nonatriene were exclusively associated with
D. plantaginea
. PTR-ToF–MS additionally detected acetic acid (AA) and 2-phenylethanol (PET) in the blends of both trees attacked by aphid species. In the wind tunnel, the aphid predator,
Chrysoperla carnea
(Stephens), responded strongly to a blend of AA and PET, much stronger than to AA or PET alone. The addition of common and species-specific HIPVs did not increase the response to the binary blend of AA and PET. In our setup, two host-associated volatiles AA + PET appeared sufficient in the attraction of
C. carnea.
Our results also show the importance of combining complementary methods to decipher the odor profile associated with plants under pest attack and identify behaviourally active components for predators.
The purpose of this work was to develop effective methods of protecting fruit crops based on the use of aphid alarm and mite aggregation pheromones. The study was conducted in 2020-2021 on a private ...farm in the Krasnodar Territory. Laboratory studies were carried out on two types of aphids: Aphis pomi Deg. and Myzus cerasi F. with the use of trans-beta-farnesene where crushed aphids of the tested species served as the source of the alarm pheromone, and insects without treatment were used as a control group. Field tests were carried out on registered trees with aphid colonies up to 10% of shoots in the crown, and mite colonies of 15-23 specimens/ leaf. Significant differences in the types of ethological reactions of apple and cherry aphids to trans-beta-farnesene were observed. In A. pomi, the predominant type was the twitching of the body during the initial period of exposure to the semiochemical. In cherry aphids, only one type of behavioral reaction to the alarm pheromone was noted, namely leaving the feeding site. The results of testing trans-beta-farnesene compositions with preparations based on biorational active substances, Phytoverm CE (2 g/l), and experimental insecticides based on coriander essential oil indicate the prospects of using the aphid alarm pheromone (trans-beta-farnesene) to increase the effectiveness of anti-aphid insecticides. Similar results were obtained in tests of trans-nerolidol, the pheromone used for aggregation of red spider mites in a composition with the Apollo, SC acaricide (500 g/l).
The native green apple aphid (
Aphis pomi
DeGeer) and the invasive green spirea aphid (
Aphis spiraecola
Patch) share apple as a common host plant during the summer months in Central Europe. Various ...studies suggest that, under certain conditions, the originally host-alternating
A. spiraecola
is able to overwinter on apple as a winter host, following a similar life history to
A. pomi
. In this study, we collected stem mothers (fundatrices) and aphids of the second generation (fundatrigeniae) from ten localities throughout Hungary for nine consecutive springs to assess whether
A. spiraecola
can overwinter on apple as a winter host. All the collected aphid individuals (1126 aphids from 114 stem colonies during the nine years of the study) belonged to
A. pomi
, indicating that
A. spiraecola
does not, or very rarely can, overwinter on apple under Central European conditions.
Цель. Изучение инсектицидной активности производных 1,3,4-оксадиазолов в отношении сокососущих вредителей садовых культур (Aphis pomi) и декоративных растений (Macrosiphum rosae).
Методы и материалы ...исследования. Материалами для исследований послужили алкилпроизводные 5-(п-Аминофенил)-1,3,4-оксадиазол-2-тиона, формулы которых приведены в тексте статьи, взрослые особи яблоневой тли (Aphis pomi) и розовой тли (Macrosiphum rosae). Методы исследования: первичный скрининг инсектицидной активности изучали методом инкубации в чашках Петри взрослых особей насекомых-вредителей. Насекомых подвергали действию веществ в течение 24 часов.
Результаты. Сокососущий вредитель – тля наносит значительный вред растениям, распространяя различные вирусы, поражающие сельскохозяйственные культуры. Для борьбы с сокососущими вредителями необходимы средства химической защиты растений с малой токсичностью для окружающей среды. По результатам скрининга доказано, что биологическая эффективность веществ 2-гексилтио-5-(п-Аминофенил)-1,3,4-оксадиазола (1), 2-октилтио-5-(п-Аминофенил)-1,3,4-оксадиазола (3) и 2-нонилтио-5-(п-Аминофенил)-1,3,4-оксадиазол (4) составляла 98.0%, 97.0% и 99.5% в отношении особи M. rosae. Под воздействием 2-гексилтио-5-(п-Аминофенил)-1,3,4-оксадиазола (1), 2-октилтио-5-(п-Аминофенил)-1,3,4-оксадиазола (3) и 2-нонилтио-5-(п-Аминофенил)-1,3,4-оксадиазола (4) в дозе 5.0 мг/мл смертность особейA. pomi достигла 99.0%, 83.0% и 90.0%, соответственно.
Впервые изучена летальная концентрация (LC50) 2-гексилтио-5-(п-Аминофенил)-1,3,4-оксадиазола (1), 2-гептилтио-5-(п-Аминофенил)-1,3,4-оксадиазола (2), 2-октилтио-5-(п-Аминофенил)-1,3,4-оксадиазола (3), 2-нонилтио-5-(п-Аминофенил)-1,3,4-оксадиазола (4) при контактном действии с насекомым.
Заключение. Таким образом, поиск и создание инсектицидов низкой токсичности для окружающей среды, предотвращающие возникновение резистентности на основе алкилпроизводных 5-(п-Аминофенил)-1,3,4-оксадиазол-2-тиона в защите растений является актуальным направлениям.
Исследование показало, что 2-гексилтио-5-(п-Аминофенил)-1,3,4-оксадиазол (1), 2-октилтио-5-(п-Аминофенил)-1,3,4-оксадиазол (3) и 2-нонилтио-5-(п-Аминофенил)-1,3,4 оксадиазол (4) в концентрации 0.5 мг/мл сильно токсичны для особей M. rosae и A. pomi.
Работа по использованию алкилпроизводных 5-(п-Аминофенил)-1,3,4-оксадиазол-2-тионов в качестве сельскохозяйственных средств защиты будут продолжены.
The Green apple aphid,
Aphis pomi
de Geer (Hemiptera: Aphididae), is one of the most common and serious insect pests of apple orchards in Turkey. This species feeds on succulent tissue of trees, ...which can lead to leaf curling, stunting, distorted tip growth, black-sooty mold, and a vector of some plant viruses. Growers prefer to apply insecticide applications heavily to control the green apple aphid in commercial apple orchards. However, there have not been conducted any research study on insecticide resistance of
A
.
pomi
in Turkey. The resistance status of
A. pomi
populations collected from commercially apple orchards in the Central Anatolia region was investigated to: acetamiprid (neonicotinoid), the specific aphicide pirimicarb (carbamate), beta-cyfluthrin (synthetic pyrethroid), and chlorpyrifos-ethyl (organophosphate) insecticides. All populations were characterised for the first time using polyacrylamide gel electrophoresis to determine the esterase banding patterns. Biochemical assays revealed higher activity of total esterase. This is the first study conducted to determine glutathione S-transferase activity related to the insecticide resistance of
A. pomi
. It was determined that the resistance levels reached to 14.93 fold to acetamiprid, 3.74 fold to beta-cyfluthrin, 4.19 fold to chlorpyrifos-ethyl, and 4.33 fold to pirimicarb. The present study revealed neonicotinoid, organophosphate, carbamate, and pyrethroid resistance in
A. pomi
populations from the Central Anatolia Regions of Turkey. It also clearly showed that the enhanced esterase enzyme activity is the main resistance mechanism against carbamate pirimicarb resistance. The present study is the first insecticide resistance study on
A. pomi
for Turkey.
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