Pest Manag Sci
December 2021
The cotton mealybug Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae), is a highly invasive and harmful pest. It causes considerable loss of cotton crops in China, India and Pakistan. Little is known about its bionomics since it was first recorded in Pakistan and India in 2005.
View Article and Find Full Text PDFTemperature is an important abiotic environmental factor, and is responsible for various kinds of behavioral and physiological changes in living organisms. Induced heat shock is associated with feeding behaviour, reproduction and reactive oxygen species (ROS) generation that causes oxidative damage. In this experiment, we examined the lethal and sublethal effects of heat shock on reproduction, feeding behaviour and antioxidant enzymes, including catalase (CAT), superoxide dismutase (SOD) and peroxidases (POD) in P.
View Article and Find Full Text PDFUsing smart nanopesticide formulations based on nanomaterials can offer promising potential applications for decreasing pesticide residues and their effects on human health and the environment. In this study, a novel nanoformulation (NF) of thiamethoxam (TMX) was fabricated using the solvent evaporation method through loading TMX on cellulose nanocrystals (CNCs) as the carrier. The synthesized TMX-CNCs was investigated through different techniques, such as Fourier transform infrared spectrometer (FT-IR), X-ray diffraction (XRD), transmission electron microscopy (TEM), dynamic light scattering (DLS), and thermogravimetric analysis (TGA).
View Article and Find Full Text PDFEffects of temperature on the development, survival, reproduction, longevity and sex ratio of the cotton mealybug, Phenacoccus solenopsis Tinsley, was assessed at five constant temperatures ranging from 20 to 35°C and five fluctuating temperatures ranging from 15 to 40°C under laboratory conditions. Results showed that nymphal development duration, preoviposition period, oviposition period, fecundity, and adult longevity were reduced significantly with increasing temperature until 30°C, but developmental duration of third female nymphal instar and female adult longevity was longer at 35°C than 30°C, and no males could emerge from pupae at the constant temperature 35°C. Fluctuating temperature, in general, significantly accelerated the nymphal developmental duration, prolonged preoviposition period, shortened oviposition period, reduced fecundity, lowered the survival rate of nymphs, and decreased adult longevity of males and females compared to their mean corresponding constant temperature.
View Article and Find Full Text PDFUsing nanotechnology to develop new formulations of pesticides is considered a possible option in enhancing the efficiency, safety, and photostability of pesticides under various climatic conditions. In the present study, two novel nanoformulations (NFs) were successfully prepared based on nano-delivery systems for emamectin benzoate (EMB) by loading it on cellulose nanocrystals (CNCs) and silicon dioxide nanoparticles (SNPs) as carriers through a freeze-drying method. The synthesized nanoformulations were examined using field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and dynamic light scattering (DLS).
View Article and Find Full Text PDFAcetamiprid and imidacloprid are two important neonicotinoid insecticides that are widely utilized under field conditions for the management of sucking insect pests, including the solenopsis mealybug Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae). Although some information is available regarding their lethal effects, nothing is currently known about the sublethal effects of these insecticides. We, therefore, performed a series of experiments to test the lethal and sublethal effects of these chemicals on oviposition duration and fecundity.
View Article and Find Full Text PDFColloidal delivery systems have been widely used as carriers for controlled delivery of pesticides to improve the efficacy and photostability of natural and semi-synthetic pesticides. In this study, we have synthesized emamectin benzoate nanoformulations (EB + NFs) depending on polymeric nanocapsules (PNC) and two types of the nanosilica, mesoporous nanosilica (MCM-48) and silicon dioxide nanoparticles (SNPs) as carriers for the emamectin benzoate (EB). The fabricated nanoformulations were characterized by using X-ray diffraction analysis, Fourier transform infrared spectroscopy, particle size, zeta potential, morphology, absolute recovery (AR), entrapment efficiency (EE), UV stability and release kinetics.
View Article and Find Full Text PDFYing Yong Sheng Tai Xue Bao
September 2012
By the methods of headspace solid-phase micro extraction and gas chromatography-mass spectrometry, and using Y-type olfactometer, this paper identified the volatiles from six tomato varieties (Zheza 809, Zheza 203, Hezuo 903, Kate No. 1, Huangtuoyan, and Jinfei), and bio-assayed the olfactory responses of female B-biotype Bemisia tabaci to the tomato plants and their released volatiles. Thirteen kinds of compounds in the volatiles collected from the six tomato varieties were identified, among which, terpenoids were the main components.
View Article and Find Full Text PDFMaximizing the contribution of endemic natural enemies to integrated pest management (IPM), programs requires a detailed knowledge of their interactions with the target pest. This experimental field study evaluated the impact of the endemic natural enemy complex of Plutella xylostella (L.) (Lepidoptera: Yponomeutidae) on pest populations in commercial cabbage crops in southeastern Queensland, Australia.
View Article and Find Full Text PDFThe toxicities of five pesticides commonly used in vegetable fields to the larvae of the diamondback moth, Plutella xylostella (L) and its two major parasitoids, Cotesia plutellae (Kurdjumov) and Oomyzus sokolowskii (Kurdjumov), were evaluated in the laboratory using several bioassays. When tested at the rates recommended for field application by the manufacturer, fipronil, avermectin and chlorfluazuron produced over 95% mortality on third-instar larvae of P xylostella, but fenvalerate and methomyl did not produce any substantial mortality to such larvae, and over 70% of P xylostella larvae could still pupate normally after feeding on cabbage leaf treated with the two pesticides. In a residual contact assay with adult parasitoids, fipronil and methomyl caused over 93% mortality within 24 h; fenvalerate killed approximately 55% of the adults within 24 h; avermectin and chlorfluazuron showed differential toxicity to the two parasitoids.
View Article and Find Full Text PDFYing Yong Sheng Tai Xue Bao
June 2003
The interspecific interactions between Cotesia plutellae (Kurdjumov) (Hym.: Braconidae) and Oomyzus sokolowskii (Kurdjumov) (Hym.: Eulophidae) were investigated at 28 degrees C in laboratory, by exposing the 3rd instar larvae of diamondback moth, Plutella xylostella L.
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