INSECTICIDE-STIMULATED REPRODUCTION OF MYZUS PERSICAE, THE GREEN PEACH APHID (HOMOPTERA: APHIDIDAE)

1984 ◽  
Vol 116 (5) ◽  
pp. 783-784 ◽  
Author(s):  
P. L. Gordon ◽  
F. L. McEwen
Keyword(s):  
Myzus Persicae ◽  
Natural Enemy ◽  
Food Supply ◽  
Green Peach Aphid ◽  
Pest Species ◽  
Direct Stimulation ◽  
Sublethal Doses ◽  
Stimulation Of

Many instances of pest populations increasing following the application of pesticides to crops have been reported, with natural enemy destruction by the pesticide often cited as the cause (Putman and Heme 1959). Other explanations include a greater food supply available due to the death of competing pest species (Root and Gowan 1978), and direct stimulation of the enhanced species by sublethal doses of a pesticide, evidenced as increased fecundity (Leigh and Wynholds 1980; Boykin and Campbell 1982; Coombes 1983). In Ontario the use of the insecticide azinphosmethyl has been followed by population increases of the green peach aphid (Myzus persicae (Sulzer)) (Founk and McClanahan 1970; Ritcey et al. 1982). Our study was undertaken to determine the causes.

Relative Toxicity and Residual Activity of Nanocapsules and Commercial Formulations of Pirimicarb and Pymetrozine Against Myzus persicae (Hemiptera: Aphididae)

2019 ◽  
Vol 112 (6) ◽  
pp. 2670-2675
Author(s):  
Nariman Maroofpour ◽  
Mir Jalil Hejazi ◽  
Hamed Hamishehkar ◽  
Shahzad Iranipour
Keyword(s):  
Myzus Persicae ◽  
Green Peach Aphid ◽  
Residual Activity ◽  
Plant Viruses ◽  
Pest Species ◽  
Relative Toxicity ◽  
Improve Performance ◽  
Wide Range ◽  
Wettable Powder ◽  
Pesticide Load

Abstract The green peach aphid, Myzus persicae (Sulzer), is one of the most common pest species that has the potential to transmit more than 100 plant viruses. Controlling this pest is difficult because it has become resistant to a wide range of insecticides. Nanoformulation has the capacity to reduce the pesticide load in agriculture and thus reduce the risks on human health and the environment. In this study, nanocapsules of pirimicarb and pymetrozine were prepared using nanostructured lipid carriers. The size, morphology, and encapsulation efficiency of nanocapsules were investigated using dynamic light scattering, scanning electron microscopy, and UV-VIS spectrophotometer. Zeta potential studies revealed stability of the nanocapsules of both insecticides. The encapsulation efficiencies were 85 and 81% for pirimicarb and pymetrozine, respectively. The nanocapsules were spherical with sizes of 35.38 and 35.12 nm for pirimicarb and pymetrozine, respectively. The LC50 values for the wettable powder (WP) and nanocapsule of pirimicarb after 48 h were 216.2 and 73.2 mg ai/l; for pymetrozine after 96 h, the values were 40.6 and 14.8 mg ai/l, respectively. Durations of residual activity for WP and nanocapsule formulations of pirimicarb were 7 and 15 d, respectively. The residual activity periods for WP and nanocapsule formulations of pymetrozine were 9 and 17 d, respectively. The results revealed that nanoencapsulation can improve performance allowing for reduced doses and increased duration of insecticidal activity for both of the insecticides tested.

scholarly journals The Gustavus Gene Can Regulate the Fecundity of the Green Peach Aphid, Myzus persicae (Sulzer)

2021 ◽  
Vol 11 ◽  
Author(s):  
Yang Gao ◽  
Ruifan Ren ◽  
Jing Peng ◽  
Dongwei Wang ◽  
Xiaobin Shi ◽  
...  
Keyword(s):  
Myzus Persicae ◽  
Green Peach Aphid ◽  
Plant Viruses ◽  
Pest Species ◽  
Partial Control ◽  
Environmentally Sustainable ◽  
Real Time Quantitative Pcr ◽  
Transcriptome Database ◽  
Conserved Gene

Myzus persicae (Sulzer), commonly known as the green peach aphid, is a notorious pest that causes substantial losses to a range of crops and can transmit several plant viruses, including potato virus Y (PVY). Chemical insecticides provide only partial control of this pest and their use is not environmentally sustainable. In recent years, many genes related to growth, development, and reproduction have been used as targets for pest control. These include Gustavus (Gus), a highly conserved gene that has been reported to play an essential part in the genesis of germline cells and, hence, in fecundity in the model insect Drosophila melanogaster. We hypothesized that the Gustavus (Gus) gene was a potential target that could be used to regulate the M. persicae population. In this study, we report the first investigation of an ortholog of Gus in M. persicae, designated MpGus, and describe its role in the fecundity of this insect. First, we identified the MpGus mRNA sequence in the M. persicae transcriptome database, verified its identity with reverse transcription-polymerase chain reaction (RT-PCR), and then evaluated the transcription levels of MpGus in M. persicae nymphs of different instars and tissues with real-time quantitative PCR (RT-qPCR). To investigate its role in regulating the fecundity of M. persicae, we used RNA interference (RNAi) to silence the expression of MpGus in adult insects; this resulted in a significant reduction in the number of embryos (50.6%, P < 0.01) and newborn nymphs (55.7%, P < 0.01) in the treated aphids compared with controls. Interestingly, MpGus was also significantly downregulated in aphids fed on tobacco plants that had been pre-infected with PVYN, concomitant with a significant reduction (34.1%, P < 0.01) in M. persicae fecundity. Collectively, these data highlight the important role of MpGus in regulating fecundity in M. persicae and indicate that MpGus is a promising RNAi target gene for control of this pest species.

Green peach aphid and potato leafroll virus: transmission and control

2020 ◽  
Author(s):  
R.A. Bagrov ◽  
◽  
V.I. Leunov
Keyword(s):  
Myzus Persicae ◽  
Green Peach Aphid ◽  
Virus Transmission ◽  
Potato Leafroll Virus ◽  
Factors Affecting ◽  
Potato Viruses ◽  
Tuber Necrosis ◽  
Aphid Vectors ◽  
Leafroll Virus ◽  
And Control

The mechanisms of transmission of potato viruses from plants to aphid vectors and from aphids to uninfected plants are described, including the example of the green peach aphid (Myzus persicae, GPA). Factors affecting the spreading of tuber necrosis and its manifestation on plants infected with potato leafroll virus (PLRV) are discussed. Recommendations for PLRV and GPA control in the field are given.

scholarly journals The Role of BMP Signaling in Osteoclast Regulation

2021 ◽  
Vol 9 (3) ◽  
pp. 24
Author(s):  
Brian Heubel ◽  
Anja Nohe
Keyword(s):  
Bone Formation ◽  
Bone Morphogenetic Proteins ◽  
Bone Diseases ◽  
Bmp Signaling ◽  
Bone Homeostasis ◽  
Direct Stimulation ◽  
Federal Drug Administration ◽  
Bmp Pathway ◽  
Stimulation Of

The osteogenic effects of Bone Morphogenetic Proteins (BMPs) were delineated in 1965 when Urist et al. showed that BMPs could induce ectopic bone formation. In subsequent decades, the effects of BMPs on bone formation and maintenance were established. BMPs induce proliferation in osteoprogenitor cells and increase mineralization activity in osteoblasts. The role of BMPs in bone homeostasis and repair led to the approval of BMP2 by the Federal Drug Administration (FDA) for anterior lumbar interbody fusion (ALIF) to increase the bone formation in the treated area. However, the use of BMP2 for treatment of degenerative bone diseases such as osteoporosis is still uncertain as patients treated with BMP2 results in the stimulation of not only osteoblast mineralization, but also osteoclast absorption, leading to early bone graft subsidence. The increase in absorption activity is the result of direct stimulation of osteoclasts by BMP2 working synergistically with the RANK signaling pathway. The dual effect of BMPs on bone resorption and mineralization highlights the essential role of BMP-signaling in bone homeostasis, making it a putative therapeutic target for diseases like osteoporosis. Before the BMP pathway can be utilized in the treatment of osteoporosis a better understanding of how BMP-signaling regulates osteoclasts must be established.

Electrical stimulation of retinal neurons in epiretinal and subretinal configuration using a multicapacitor array

2012 ◽  
Vol 107 (10) ◽  
pp. 2742-2755 ◽  
Author(s):  
Max Eickenscheidt ◽  
Martin Jenkner ◽  
Roland Thewes ◽  
Peter Fromherz ◽  
Günther Zeck
Keyword(s):  
Electrical Stimulation ◽  
Ganglion Cells ◽  
Ex Vivo ◽  
Biophysical Model ◽  
Retinal Neurons ◽  
Direct Stimulation ◽  
Tungsten Electrode ◽  
Partial Restoration ◽  
Low Amplitude ◽  
Stimulation Of

Electrical stimulation of retinal neurons offers the possibility of partial restoration of visual function. Challenges in neuroprosthetic applications are the long-term stability of the metal-based devices and the physiological activation of retinal circuitry. In this study, we demonstrate electrical stimulation of different classes of retinal neurons with a multicapacitor array. The array—insulated by an inert oxide—allows for safe stimulation with monophasic anodal or cathodal current pulses of low amplitude. Ex vivo rabbit retinas were interfaced in either epiretinal or subretinal configuration to the multicapacitor array. The evoked activity was recorded from ganglion cells that respond to light increments by an extracellular tungsten electrode. First, a monophasic epiretinal cathodal or a subretinal anodal current pulse evokes a complex burst of action potentials in ganglion cells. The first action potential occurs within 1 ms and is attributed to direct stimulation. Within the next milliseconds additional spikes are evoked through bipolar cell or photoreceptor depolarization, as confirmed by pharmacological blockers. Second, monophasic epiretinal anodal or subretinal cathodal currents elicit spikes in ganglion cells by hyperpolarization of photoreceptor terminals. These stimuli mimic the photoreceptor response to light increments. Third, the stimulation symmetry between current polarities (anodal/cathodal) and retina-array configuration (epi/sub) is confirmed in an experiment in which stimuli presented at different positions reveal the center-surround organization of the ganglion cell. A simple biophysical model that relies on voltage changes of cell terminals in the transretinal electric field above the stimulation capacitor explains our results. This study provides a comprehensive guide for efficient stimulation of different retinal neuronal classes with low-amplitude capacitive currents.

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