Detection of maize yellow stripe tenui-like virus by ELISA and dot- blot tests in host plants and leafhopper vector in Egypt

Antisera to the nucleoprotein of maize yellow stripe tenui-like virus (MYSV) were produced and used for detection of this virus in several host plants and vector leafhoppers in Egypt. Dot-blot and direct antigen coating (DAC) ELISA were used to detect MYSV in naturally or experimentally infected maize, wheat, barley, oats, and the graminaceous weeds #Bromus wildenowii, #Cenchrus biflorus, #Dichanthium annulatum, #Digitaria sanguinalis, #Echinochloa colonum, #Setaria verticillata and #S. viridis. In maize leaves, differences in virus titer appeared to be correlated with leaf age and with MYSV symptom-types. Dot-blot and DAC-ELISA were used also to detect MYSV in naturally or experimentally infective leafhoppers (#Cicadulina chinai). (Résumé d'auteur

Gut Extracts of Rhynchophorus ferrugineus Larvae Olivier Affecting Bacterial Dental Caries

In vitro study was conducted to explore antibacterial properties of the larval gut extracts of Rhynchophorus ferrugineus (Red Palm Weevil) Oliver. Larval gut extracts were tested against salivary bacteria causing dental carries using the agar well diffusion method. The gut extracts significantly affected the growth of both Klebsiella spp. and Streptococcus viridans. The two bacterial species revealed significant differences in their sensitivity to the extract. The extract efficacy depended upon the concentration and time of exposure. When using 100%concentration of the extract, the mean of inhibition zones for S. viridans and Klebsiella spp. at 24 h after treatment were 1.61 mm and 2.50 mm, respectively. At 48 h post-treatment, the mean of inhibition zones for S. viridans and Klebsiella spp. were 1.96 mm and 2.66 mm. After 72 hours, the means zones were 2.28 mm and 2.91 mm, respectively. Electron microscopic examinations showed morphological changes of the outer membrane of bacteria with a noticeable damage as a result of exposure to the gut extract. The results suggest potential use of these extracts against dental caries bacteria

Characterization and serology of the leafhopper-borne maize yellow stripe virus in Egypt

The nucleoprotein and non-capsid protein of maize yellow stripe virus (MYSV) were purified from naturally or experimentally infected maize or sorghum plants. In SDS-PAGE, the apparent molecular weight of the nucleoprotein was 35,6 KD, and that of the non-capsid protein was 14,7 KD. Similar to tenuiviruses, the nucleoprotein of MYSV was associated with fine filaments and the non-capsid protein formed typical needle-shaped crystals. Following a 2-day acquisition feeding period on MYSV-infected plants, vector leafhoppers (#Cicadulina chinai) remained highly infective for 21 days. Antisera to the nucleoprotein and non-capsid protein of MYSV were produced and used for detection of this virus in several host plants and vector leafhoppers in Egypt. Dot-blot and direct antigen coating (DAC) ELISA were used to detect MYSV in naturally or experimentally infected maize, wheat, barley, oat and the graminaceous weeds #Bromus wildenowii, #Cenchrus biflorus, #Dichanthium annulatum, #Digitaria sanguinalis, #Echinochloa colonum, #Setaria viridis and #S. verticillata. Dot-blot and DAC-ELISA were used also to detect MYSV in naturally or experimentally infective leafhoppers. (Résumé d'auteur

Characterization and serology of the leafhopper-borne maize yellow stripe virus in Egypt

The nucleoprotein and non-capsid protein of maize yellow stripe virus (MYSV) were purified from naturally or experimentally infected maize or sorghum plants. In SDS-PAGE, the apparent molecular weight of the nucleoprotein was 35,6 KD, and that of the non-capsid protein was 14,7 KD. Similar to tenuiviruses, the nucleoprotein of MYSV was associated with fine filaments and the non-capsid protein formed typical needle-shaped crystals. Following a 2-day acquisition feeding period on MYSV-infected plants, vector leafhoppers (#Cicadulina chinai) remained highly infective for 21 days. Antisera to the nucleoprotein and non-capsid protein of MYSV were produced and used for detection of this virus in several host plants and vector leafhoppers in Egypt. Dot-blot and direct antigen coating (DAC) ELISA were used to detect MYSV in naturally or experimentally infected maize, wheat, barley, oat and the graminaceous weeds #Bromus wildenowii, #Cenchrus biflorus, #Dichanthium annulatum, #Digitaria sanguinalis, #Echinochloa colonum, #Setaria viridis and #S. verticillata. Dot-blot and DAC-ELISA were used also to detect MYSV in naturally or experimentally infective leafhoppers. (Résumé d'auteur