Laboratory Effects of Ingestion of Azadirachtin by Two Pests ( Ceratitis capitata and Spodoptera exigua ) and Three Natural Enemies ( Chrysoperla carnea , Opius concolor and Podisus maculiventris )

Aphids are the most important pests on wheat in Egypt and worldwide. Field trials were conducted to assess the efficacy of the neonicotinoid insecticides imidacloprid (Nufidor 60% FS; at the doses of 2.1, 1.05 and 0.525 g a.i./kg of seeds) and thiamethoxam (Cruiser 70% WS; at the rates of 14.4, 7.2 and 3.6 g a.i./kg of seeds) as seed treatments, and thiamethoxam (Actara 25% WG; at the rates of 0.1, 0.05 and 0.025 g a.i./l) as foliar application, against three wheat aphids: bird cherry oat aphid, Rhopalosiphum padi (L.), greenbug, Schizaphis graminum (Rondani), and corn leaf aphid, Rhopalosiphum maidis (Fitch). Their effects on the aphids? natural enemies: lacewings, Chrysoperla carnea Stephens, ladybird beetles, Coccinella spp., and syrphid flies Syrphus spp. were assessed as well. The trials were conducted on the farm of the Faculty of Agriculture, Suez Canal University, Ismailia Governorate, during 2013/14 and 2014/15 seasons. Our results showed significant differences between the tested insecticides at all concentrations and clearly indicated that the recommended doses of all insecticides were more efficient against aphids on wheat plants than half- and quarter-doses. Also, the data revealed significant differences between the two seed treatments at all doses before and after foliar application, as compared to the control at all time intervals of inspection regarding the mean number of aphids on wheat plants, from the 3rd until 13th week after sowing, except in the 8th week after seed treatment before foliar application. The results clearly indicated that the weekly reduction of infestation and the general efficacy was higher at the recommended doses of Nufidor, Cruiser and Actara than the half and quarter doses in both seasons. Also, reduction in infestation decreased over the following weeks until the 8th week, when Actara insecticide was sprayed. Data revealed that there were no significant differences between treatments and control in the mean number of Chrysoperla carnea and Syrphus spp., while a significant difference in the mean number of coccinellids was observed on wheat plants treated with imidacloprid seed treatment before foliar application 6 and 7 weeks after sowing, and also after foliar application with thiamethoxam 9, 10, 11, 12 and 13 weeks after sowing. Regarding thiamethoxam seed treatment, significant differences were revealed in the ladybird population on wheat plants 3, 4, 7 and 8 weeks before foliar application, and only in the 10th week after spraying with thiamethoxam.

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Effects of Nitrogenous Fertilization and some Insecticides on the Natural Enemies of Transgenic Bt Cotton Pests

EntomoBrasilis ◽

10.12741/ebrasilis.v14.e948 ◽

2021 ◽

Vol 14 ◽

pp. e948

Author(s):

Mamoun Fadlelmawla ◽

Azhari Abdelbagi ◽

Abd Elaziz Ishag ◽

Ahmed Hammad ◽

Jang-Hyun Hur

Keyword(s):

Natural Enemies ◽

Nitrogen Fertilization ◽

Integrated Management ◽

The Other ◽

Chrysoperla Carnea ◽

Bt Cotton ◽

Percentage Reduction ◽

Cotton Pests ◽

Field Assessment ◽

Chemical Groups

Field assessment of integrated management of BT cotton pests was carried out in two consecutive seasons; 2016/2017 and 2017/2018 in the experimental research farm of the Kassala University, Sudan. Four insecticides (imidacloprid, abamectin, profenofos, and lufenuron) from different chemical groups and with a different mode of action and three levels (43.81 kgha-1, 87.62 kgha-1, and 131.43 kgha-1) of soil-applied nitrogen were tested in the IPM package. Insecticides were applied at the recommended doses. A total of 7 weekly counts of prevailing natural enemies [Chrysoperla carnea (Stephens) and Aenasius bambawalei Hayat] were carried out for 4 weeks before spraying and 3 weeks post spraying starting the 3rd week from spraying. Results indicated that nitrogen level exerted no significant effects on the populations of prevailing natural enemies; C. carnea and A. bambawalei. Based on average post spray counts and percentage reduction over the control, all insecticide treatments significantly reduced the population of the natural enemies. Imidacloprid and profenofos exerted the highest reduction of C. carnea population followed by abamectin and lufenuron (56.03, 48.25, 07.78 and 06.61% respectively) in the first season, while profenofos, imidacloprid, lufenuron, and abamectin induced the highest reductions (55.94, 45.05, 17.57 and 17.33% respectively) in the second season. On the other hand, reductions in A. bambawalei population (abundant in season 1 only) followed the order; imidacloprid, lufenuron, abmectin, and profenofos (03.95, 02.63, 202.63, and 01.32%, respectively). Interactions between nitrogen fertilization and insecticide were not significant as measured by the population of prevailing natural enemies.

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Natural enemies of the beet armyworm, Spodoptera exigua (Huebner) and their seasonal prevalence in Kagoshima Prefecture.

Kyushu Plant Protection Research ◽

10.4241/kyubyochu.38.142 ◽

1992 ◽

Vol 38 ◽

pp. 142-145

Author(s):

Hiroshi YOKOYAMA ◽

Akira TANAKA ◽

Hiroshi SUENAGA ◽

Hideaki INOUE ◽

Kanetosi KUSIGEMATI

Keyword(s):

Natural Enemies ◽

Spodoptera Exigua ◽

Beet Armyworm ◽

Seasonal Prevalence ◽

Kagoshima Prefecture

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Can Herbivore-Induced Volatiles Protect Plants by Increasing the Herbivores’ Susceptibility to Natural Pathogens?

Applied and Environmental Microbiology ◽

10.1128/aem.01468-18 ◽

2018 ◽

Vol 85 (1) ◽

Cited By ~ 7

Author(s):

Laila Gasmi ◽

María Martínez-Solís ◽

Ada Frattini ◽

Meng Ye ◽

María Carmen Collado ◽

...

Keyword(s):

Pest Management ◽

Natural Enemies ◽

Plant Volatiles ◽

Spodoptera Exigua ◽

Negative Impact ◽

Microbiota Composition ◽

Content Type ◽

Induced Plant Volatiles ◽

Induced Volatiles ◽

Herbivore Induced Plant Volatiles

ABSTRACTIn response to insect herbivory, plants mobilize various defenses. Defense responses include the release of herbivore-induced plant volatiles (HIPVs) that can serve as signals to alert undamaged tissues and to attract natural enemies of the herbivores. Some HIPVs can have a direct negative impact on herbivore survival, but it is not well understood by what mechanisms. Here, we tested the hypothesis that exposure to HIPVs renders insects more susceptible to natural pathogens. Exposure of the caterpillars of the noctuidSpodoptera exiguato indole and linalool, but not exposure to (Z)-3-hexenyl acetate, increased the susceptibility toSpodoptera exiguamultiple nucleopolyhedrovirus(SeMNPV). We also found that exposure to indole, but not exposure to linalool or (Z)-3-hexenyl acetate, increased the pathogenicity ofBacillus thuringiensis. Additional experiments revealed significant changes in microbiota composition after forty-eight hours of larval exposure to indole. Overall, these results provide evidence that certain HIPVs can strongly enhance the susceptibility of caterpillars to pathogens, possibly through effects on the insect gut microbiota. These findings suggest a novel mechanism by which HIPVs can protect plants from herbivorous insects.IMPORTANCEMultitrophic interactions involving insect pests, their natural enemies, microorganisms, and plant hosts are increasingly being recognized as relevant factors in pest management. In response to herbivory attacks, plants activate a wide range of defenses that aim to mitigate the damage. Attacked plants release herbivore-induced plant volatiles (HIPVs), which can act as priming signals for other plants and attract natural enemies of herbivores, and which may have a direct negative impact on herbivore survival. In the present work, we show that exposure of the insects to the induced volatiles could increase the insects’ susceptibility to the entomopathogens naturally occurring in the plant environment. These findings suggest a novel role for plant volatiles by influencing insect interactions with natural pathogens, probably mediated by alterations in the insect microbiota composition. In addition, this work provides evidence for selectable plant traits (production of secondary metabolites) that can have an influence on the ecology of the pests and could be relevant in the improvement of pest management strategies using natural entomopathogens.

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The effect of Chrysoperla carnea (Neuroptera: Chrysopidae) and Adalia bipunctata (Coleoptera: Coccinellidae) on the spread of cucumber mosaic virus (CMV) by Aphis gossypii (Hemiptera: Aphididae)

Bulletin of Entomological Research ◽

10.1017/s0007485314000534 ◽

2014 ◽

Vol 105 (1) ◽

pp. 13-22 ◽

Cited By ~ 5

Author(s):

A. Garzón ◽

F. Budia ◽

P. Medina ◽

I. Morales ◽

A. Fereres ◽

...

Keyword(s):

Cucumber Mosaic Virus ◽

Mosaic Virus ◽

Natural Enemies ◽

Transmission Rate ◽

Aphis Gossypii ◽

Distribution Patterns ◽

Adalia Bipunctata ◽

Cucumber Plant ◽

Chrysoperla Carnea ◽

Source Plant

AbstractThe effects of two aphidophagous predators, the larvae of Chrysoperla carnea and adults of Adalia bipunctata, on the spread of cucumber mosaic virus (CMV) transmitted in a non-persistent manner by the cotton aphid Aphis gossypii were studied under semi-field conditions. Natural enemies and aphids were released inside insect-proof cages (1 m ×1 m ×1 m) with a central CMV-infected cucumber plant surrounded by 48 healthy cucumber seedlings, and the spatiotemporal dynamics of the virus and vector were evaluated in the short and long term (1 and 5 days) in the presence and absence of the natural enemy. The spatial analysis by distance indices methodology together with other indices measuring the dispersal around a single focus was used to assess the spatial pattern and the degree of association between the virus and its vector. Both natural enemies significantly reduced the number of aphids in the CMV-source plant after 5 days but not after 1 day. The CMV transmission rate was generally low, especially after 1 day, due to the limited movement of aphids from the central CMV-source plant, which increased slightly after 5 days. Infected plants were mainly located around the central virus-infected source plant, and the percentage of aphid occupation and CMV-infected plants did not differ significantly in absence and presence of natural enemies. The distribution patterns of A. gossypii and CMV were only coincident close to the central plant. The complexity of multitrophic interactions and the role of aphid predators in the spread of CMV are discussed.

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Comparative toxicities of some insecticides to Chrysoperla carnea (Chrysopidae: Neuroptera) and trichogramma brasiliensis (Trichogrammatidae: Hymenoptera), two arthropod natural enemies of cotton pests

Agriculture Ecosystems & Environment ◽

10.1016/0167-8809(86)90110-6 ◽

1986 ◽

Vol 15 (1) ◽

pp. 23-30 ◽

Cited By ~ 13

Author(s):

Parm Pal Singh ◽

Gurdial Chand Varma

Keyword(s):

Natural Enemies ◽

Chrysoperla Carnea ◽

Cotton Pests ◽

Trichogramma Brasiliensis

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Natural Enemies of the Sugar Beet Army Worm, Spodoptera exigua (Lepidoptera: Noctuidae) in Northeast Iran

Entomological News ◽

10.3157/021.127.0508 ◽

2018 ◽

Vol 127 (5) ◽

pp. 446-464 ◽

Cited By ~ 1

Author(s):

Reyhaneh Darsouei ◽

Javad Karimi ◽

Mohammad Ghadamyari ◽

Mojtaba Hosseini

Keyword(s):

Sugar Beet ◽

Natural Enemies ◽

Spodoptera Exigua ◽

Lepidoptera Noctuidae ◽

Beet Army Worm ◽

Northeast Iran ◽

Army Worm

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Host Availability, Repulsive Companion Planting, and Predation Interact and Shape How a Parthenogenetic Aphid Population Responds to a Stratified Ecological Challenge

10.20944/preprints202001.0140.v1 ◽

2020 ◽

Author(s):

Mouhammad Shadi Khudr ◽

Lea Fliegner ‎ ◽

Oksana Y. Buzhdygan ◽

Samuel Alexander Purkiss

Keyword(s):

Natural Enemies ◽

Green Peach Aphid ◽

Chrysoperla Carnea ◽

Strong Impact ◽

Adaptive Responses ◽

Functional Biodiversity ◽

Host Availability ◽

Allium Cepa L ◽

Negative Impacts ◽

Phloem Feeding

Phloem-feeding insects strive to offset the disadvantageous effects of stressors to sustain their offspring and survive. Adaptive responses to environmental stress are not well understood under complex influences of companion planting, natural enemies, and host gradient. In this study, under predation by lacewing Chrysoperla carnea Stephens (Neuroptera: Chrysopidae), we survey the responses of green peach aphid Myzus persicae Sulzer (Hemiptera: Aphididae), reared on different densities of cabbage Brassica oleracea L. (Brassicales: Brassicaceae) to its shallot companion Allium cepa (L.) var. aggregatum G. Don (Asparagales: Amaryllidaceae). Firstly, aphid aggregative abundance was strongly influenced by shallot perturbation, predator presence and changes in cabbage-host biomass, altering aphid phenotypic plasticity. Interestingly, the shallot and predation negative impacts can be of similar magnitudes. Secondly, changes in the cabbage-host availability and biomass, especially under predation, had a strong impact on aphid traits. Our study underscores the benefits of including shallots as crop-companions in augmenting pest control, but also suggests that the outcome of coupling companion planting with natural enemies is context-dependent and thus should be empirically applied. At the confluence of ecology and agronomy, this work provides insights on how manipulated functional biodiversity may function as an alternative strategy for pestilent herbivory management in model and green-house systems.

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