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Tobaco mosaic virus (TMV) is a deadly plant virus with serious economic implications resulting in decrease crop-yield production. In recent years, environmentally friendly components for managing crop diseases have been developed as alternatives to chemical pesticides, including the use of agrowaste like pomegranate peels. Our studies were carried out to determine the chemical constituents of pomegranate peels and their sonicated nanoparticles. The present study is aimed to study the toxic effect of Tobaco mosaic virus (TMV) infections with either pomegranate peels (PPs) and their nanoparticles (PPNPs) extract treatments as antioxidant and antiviral agent by using the local lesion assay on Datura metel. The virus was obtained from infected tobacco plants. The pomegranate peels were extracted by phosphate buffer, pH7.2 and the homogenates were used itself or after developed based on the ultrasound then the transmission electron microscopy (TEM) analysis showed that nanoparticles ranged from 15- to 30 nm. Chemical composition compounds were determined; also, genetic diversity of plant samples was estimated using RAPD and ISSR molecular markers. Our results showed that the antiviral extracts of PPs and PPNPs used had significant effects in decreasing the number of local lesions formed by the challenge inoculation of TMV. The PPNPs extract was found to be the highest effective against TMV, which may be due to their chemical composition which contain high concentrations of monosaccharides, amino acids, phenolic and flavonoids compounds and antioxidant activity (DPPH). In addition, Results showed that tested extracts obtained from PPS or PPNP have no effect on DNA of Datura metel Plants. At the same time, the viral infection was inhibited, which made them safe as biological materials. Therefore, this study recommends the application of the agrowaste (PPS or PPNPs) as ecofriendly antiviral. [ABSTRACT FROM AUTHOR]

Fipronil and emamectin benzoate (EMB) are effective insecticides for controlling cotton leafworm, Spodoptera littoralis. Fipronil works by blocking gamma-amino butyric acid (GABA) gated chloride. In contrast, EMB is activating GABA transporters. The objectives of our study were to assess relative toxicity of the technical fipronil and EMB alone and in mixture against S. littoralis. In addition, the GABA content was simultaneously determined using HPLC. Technical fipronil and EMB and their mixtures were applied topically to the fourth-instar larvae, and their LD50 values were estimated after 48 h. Results demonstrated that the LD50 for EMB applied alone was 0.751 ng/larva which was much less than for fipronil 7.271 ng/larva. Each of the two insecticides alone showed a significant decrease in GABA content at LD10, LD25, and LD50 doses, while their mixtures induced GABA levels. The highest potentiation was observed when both insecticides were in a mixture at the ratio of LD10:LD10 which was associated with higher increase in GABA levels. Moreover, the weight of the alive larvae was less than that was in the untreated control. However, all mixtures exhibited potentiation effect, except for the mixture of fipronil at LD50 with EMB at LD10, LD25, and LD50 that had antagonistic effect correlated with the lowest decrease in GABA level. Results suggested that lower doses of both insecticides in a binary mixture had potentiation effect against S. littoralis. This mixture could be used in combination as field application for successful and effective control of S. littoralis and would also help in managing insecticide resistance. [ABSTRACT FROM AUTHOR]

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Copyright of Journal of Plant Protection & Pathology is the property of Egyptian National Agricultural Library (ENAL) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)