Background Gastropods are very prevalent animals. In Egypt, terrestrial snails represent important economic pests, infesting and causing severe damages to ornamental plants, orchard trees, vegetables, and field crops. The overuse of molluscicides against these destructive pests leads to more environmental pollution. Therefore, searching for biological control agents became necessary to avoid the hazard of chemical molluscicides. Phasmarhabditis hermaphrodita, isolated from slugs was used as a bio-control agent against snails and slugs. Few investigations available on gastropod egg parasites. Therefore, the present study interested in the isolation of parasitic nematodes from the snail eggs to study their possible role as biological control agents for gastropod pests. Results This is the first record to isolate the snail parasitic nematode, Phasmarhabditis sp., from eggs of the Egyptian terrestrial snail, Eobania vermiculata (Müller). Infectivity of this nematode was investigated for eggs, juvenile and mature snails, E. vermiculata and Limax flavus L. slugs, and also eggs of the non-local species, Achatina fulica Bowdich and one adult of it was only available. The investigation revealed a capability of the isolated nematode to infect and kill E. vermiculata snail, L. flavus slugs, and their eggs. Also, it could infect and kill the eggs of non-local snail species, A. fulica, and its only individual adult available which was obtained from an agricultural quarantine sample. The results indicated also that released individuals of the nematodes, recovered from snails, were significantly larger in size than those recovered from eggs and vice versa. Conclusion It could be concluded that the isolated parasitic nematode may be able to play a role in controlling different stages of the gastropods including eggs. This make the control more effective in protecting host plants before the pest causing damage. The nematode was more effective on local pest species than non-local species. Moreover, the size of the parasite was proportional with the size of the host pest.

The journal of Toxicology and pest control is one of the series issued twice by the Egyptian Academic Journal of Biological Sciences, and is devoted to publication of original papers related to the interaction between insects and their environment. The goal of the journal is to advance the scientific understanding of mechanisms of toxicity. Emphasis will be placed on toxic effects observed at relevant exposures, which have direct impact on safety evaluation and risk assessment. The journal therefore welcomes papers on biology ranging from molecular and cell biology, biochemistry and physiology to ecology and environment, also systematics, microbiology, toxicology, hydrobiology, radiobiology and biotechnology. www.eajbs.eg.net Provided for non-commercial research and education use. Not for reproduction, distribution or commercial use.

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The effect of clodinafop –propargyl against the mucus of land snail, Helix aspersa, was studied under laboratory and field conditions during autumn 2020 season. Snails were exposed to serial concentrations of the clodinafop-propargyl for successive seven days using contact and bait techniques. The Median Lethal concentration (LC50) was determined and the effect of LC25 of test compound was examined on the total protein and alkaline phosphatase after seven days of treatment. In the field, the effect of the test compound used poison bait was evaluated after 21 days against H. aspersa on mango nursery trees at a reclaimed land in Abu- Rwash, Giza Governorate, Egypt. The effect of clodinafop –propargyl (25.200 ppm) was compared with methomyl (4.000 ppm) a compound recommended by Ministry of Agriculture and Land Reclamation in the field trials. The effects were evaluated after 1, 3,7, 15, and 21 days of treatment with both compounds. Based on the laboratory data for clodinafop –propargyl the LC50 were 6.750 ppm for the contact and 8.250 ppm for the bait method after seven days of treatment. Moreover, the compound caused a reduction in the total protein and alkaline phosphatase compared with the control. In the field, the compound caused 90.7% reduction in snail population compared to 75.0% reduction caused by methomyl after 21 days of treatment. Therefore, it be concluded that clodinafop –propargyl compound can be used as poison bait in the control programs to combat land snails

The field efficiency of three rodenticide baits were evaluated.They were Zinc phosphide 1.5% , Coumatetralyl 0.0375% and Brodifacoum 0.005%. Filed trials were carried out in wheat fileds at Etay El-Baroud Research Station El-Behera Governorate infested with wild Rattus rattus. The population reduction because of using Coumatetralyl only bait was 63.33% while the efficiency of Brodifacoum bait was 67.66 %. The efficiency of Zinc phosphide bait 1.5%, (crushed maize 98.5%) was only 44.47 %. The efficiency of Zinc phosphide bait 1.5% ,sunflower seeds 96.5%, corn oil 2% and Zinc phosphide bait 1%,sunflower 98% ,corn oil 1% were 57.27% and 34.6% , respectively.