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The capability of Phasmarhabditis tawfiki Azzam to control the snails Eobania vermiculata (Müller) and Theba pisana (Müller) and the insect larvae of Agrotis ipsilon (Hüfngel) and Spodoptera littoralis (Boisd.) was investigated under greenhouse conditions, using three types of soils (clay, mixture of sand and clay, and sand), using an infective dose of about 200 I.S per snail or larva for four weeks .The mortality rate of Eobania vermiculata (Müller), Theba pisana (Müller), Agrotis ipsilon (Hüf.) and Spodoptera littoralis (Boisd.) exposed to infection with P. tawfiki was 88.94, 83.75, 93.75 and 71.25 %, respectively in the clay soil. In the mixture of sand and clay soil, these rates were 67.5, 72.5, 70 and 60 % ,while in the sand soil they recorded, 53.75, 63.75, 62.5 and 52.5 %, respectively.The highest number of recovered nematodes (14579.09 I.S./snail) was reported for the snail E. vermiculata infected in the clay soil. Reversely, the lowest number(2560 I.S./larva) was associated with larvae S. littoralis in the sandy soil. T. pisana and A. ipsilon recorded 9807.17 I.S./snail and 6803.28 I.S./ larva respectively in the clay soil.Rates of individuals recovered nematodes in the clay soil were 89.94, 85.04, 82.79 and 79.01 % for E. vermiculata, T. pisana, A. ipsilon and S. littoralis, respectively.

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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.

Effect of lupine extracts nanoparticles (NPs) coated with copper sulphate on the mortality and eggs productivity of aquatic snails, Biomphalaria alexandrina Ehrenberg and Bulinus truncatus Audouin, and terrestrial snail, Eobania vermiculata Müller, were investigated in comparison with copper sulphate nanoparticles and both treatments compare with untreated group in the present and previous investigation. This experiment was planned to elucidate the molluscicidal properties of lupine extract coated with CuSO4 NPs against adult B. alexandrina B. truncatus and E. vermiculata snails after 24 hours exposure, in dark conditions, followed by another 48 hrs. light for recovery. The results revealed that lupine extracts nanoparticles has more effect than copper sulphate nanoparticles on both aquatic or terrestrial snail mortality. It caused 100% mortality for B. alexandrina and B. truncates, at concentration of 20 ppm, after 24 hours of exposure in dark followed by 48 hours recovery in day light. Copper sulphate nanoparticles at the same concentration caused only 70% and 46. 67% mortality for B. alexandrina and B. truncates, respectively, under the same conditions. Mortality rate increased with the increase of concentrations either in lupine NPs or CuO4 NPs. On normal lupine extract the concentration that caused 100% mortality was equal to ten folds of lupine NPs. Egg productivity of the healthy thirty individuals, of B. alexandrina, B. truncatus and E. vermiculata, were investigated and compared with the survival snails in low concentrations of both Cu NPs and lupine NPs, to study the effect of nanoparticle materials on the snail fecundity. Both lupine extract nanoparticles and copper sulphate nanoparticles may have a sterilized effect, where B. alexandrina and B. truncatus snails exposed to sub lethal doses from them didn't laid any egg masses after treatment. E. vermiculata, treated or untreated individuals, didn't laid any eggs either, because it had a specific season of reproduction which not coinciding with the time of experiment