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This research was conducted during 2021 and 2024 in the Biodiversity Laboratory of National Commission for Biotechnology (NCBT) and the laboratories of the Plant protection Department at the Faculty of Agricultural Engineering at Damascus University. This study aimed to detect some chemical compounds of Phytolacca americana L., and the effect of aqueous extracts of Phytolacca americana on the life span and stimulation (strengthening) of the immune system of the honey bee worker Apis mellifera, and combating the Varroa destructor Oud parasite. A number of bee samples were collected from the apiary of the Faculty of Agriculture at Damascus University during the period between March and September of the years (2021 to 2023). A set of primers specialized in detecting the most widespread honey bee viruses in the world were used. The results of the chemical analysis of the aqueous extracts of the plant parts (leaves - fruits - roots - branches) of Phytolacca americana L. showed that all extracts contained varying proportions of phenols, tannins and saponins. The highest content of phenols and tannins was recorded in the aqueous extract of the leaves of Phytolacca americana, reaching 128 µg / ml and 79.2 µg / ml, respectively. The aqueous extracts of the different plant parts of Phytolacca americana showed a significant positive effect on the average life span of the honey bee worker compared to the control. There were no significant differences between the two treatment methods, whether spraying or feeding. The highest effect was for the leaf extract at a concentration of 100 ppm, where the average number of workers that remained alive was 76%. The average increase in the life span of the honey bee worker was 52.6% compared to the untreated control. The leaf extract at a concentration of 100 ppm also gave positive results by spraying to control Varroa mites, with an average relative effectiveness of 83.3% compared to the control treated with distilled water spraying. The average ratio between pre- and post-application shedding (double), which is the number of times the number of Varroa mites falling after 24 hours of treatment compared to the average natural shedding before treatment, was 6.2 times compared to the control, which was 1.6 times. The ratio between the average shedding after one hour of treatment compared to the average total shedding after 24 hours of treatment was 54.2%. In addition to the above, when studying the efficiency of the leaf extract at a concentration of 100 ppm in stimulating the immune system of honey bee workers through the appearance of antimicrobial peptides (hymenoptycin, abasin, defensin and apidisin), it showed positive results in increasing the number of honey bee workers that remained alive and which were added to the feeding solution with a suspension of DWV virus and the plant extract, as they remained alive for 12 days compared to workers that were fed on a sugar solution only, as they remained alive for 10 days, and workers that were fed on a sugar solution and a virus suspension lived for only three days.
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Keywords: Phytolacca americana L., honey bees, Varroa, DWV virus, plant extracts, phenols.
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