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Abstract the hatching period of these eggs increased by the infection with T. alb um. M. anisopliae recorded the highest mortality of E. vermiculata produced juveniles while B. bassiana caused the highest mortality of M. cartusiana produced juveniles. By dipping, V. albo-atrum and T. album achieved the highest effect on the egg hatching of E. vermiculata and M. cartusiana eggs, respectively. T. album increased the incubation period of E. vermiculata eggs but V. albo-atrum gave the same effect against the The molluscicidal activity of 8 fungal isolates (Beauveria bassiana, Metarhizium anisopliae, Paecilomyces lilacinus, Paecilomyces variotii, Trichoderma album, Trichoderma harzianum, Trichoderma viride and Verticillium albo-atrum) was studied against adults, eggs and juveniles of two land snail species, Eobania vermiculata and Monacha cartusiana under laboratory conditions. Results showed that P. lilacinus and T. album were the most effective fungi against the adults of both snail species. By spraying technique, some fungi as B. bassiana, T. album and T. viride prevented the egg hatching of E. vermiculata snail and V. albo-atrum exhibited the same effect against the eggs of the two snail species. The incubation period of E. vermiculata eggs was elongated by the infection with P. lilacinus while T. harzianum increased the hatching period of these eggs and the same fungus caused an increasing of the incubation period of M. cartusiana eggs and incubation period and hatching period of M. cartusiana eggs and it also caused the highest mortality of the produced juveniles of this snail. B. bassiana and M. anisopliae were the most effective fungi against E. vermiculata juveniles (6 months age) while M. cartusiana juveniles were highly affected by T. album and V. albo-atrum. P. lilacinus and T. album recorded the highest reduction of both snail species in the field at the highest tested concentration 4×103 spores/ml. On the other hand, acetic acid, salicylic acid, ammonium nitrate, urea, chlorpyrifos and methomyl were tested against the different ages of both snail species. Ammonium nitrate and methomyl were the most toxic compounds against adults of the two snails. The all tested compounds prevent the egg hatching of both snails by spraying except the low concentrations of acetic acid which allow eggs for hatching. By dipping, urea and methomyl at the highest concentration were the most effective compounds against the hatching of E. vermiculata and M. cartusiana eggs, respectively. The incubation period and hatching period of eggs of the two snails were increased by increasing the concentrations of all tested compounds except acetic acid which caused decreasing in these periods by increasing its concentration and the produced juveniles of both snails were completely killed by methomyl. Urea, chlorpyrifos and methomyl were the most toxic compounds against E. vermiculata juveniles (6 months age), while the juveniles of M. cartusiana were highly killed by ammonium nitrate and methomyl. In the field, salicylic acid and urea were the superior compounds against E. vermiculata and M. cartusiana snails, respectively. The mixing of each P. lilacinus, P. variotii and T. album with each of 0.5, 1, 1.5 and 2% concentrations of ammonium nitrate and 0.5 and 1% of urea were tested against the different ages of both snail species. P. variotii + ammonium nitrate (1.5%) gave the highest toxicity against adults of both snails. All mixtures completely reduced the egg hatching of the two snails by spraying but by dipping, T. album + urea (1%) was the highest effective mixture against the egg hatching of these snails. T. album + ammonium nitrate (2%) elongated the incubation period of both snail eggs but the hatching period of these eggs increased specially by T. album + urea (1%). T. album + ammonium nitrate (2%) was the most toxic mixture against the produced juveniles of the two snails. While, the juveniles (6 months age) of E. vermiculata and M. cartusiana were highly killed by P. variotii + ammonium nitrate (2%) and T. album + urea (1%) mixtures, respectively. Under the field conditions, P. lilacinus + urea (1%) recorded the highest reduction of both snail species. |