Document Type : Original Article


1 Plant Prot. Res. Inst., Agric. Res. Cent., Dokki, Giza, Egypt

2 Plant Prot. Dept., Fac. Agric., Zagazig Univ., Egyp

3 . Plant Prot. Dept., Fac. Agric., Zagazig Univ., Egyp


Results of a survey carried out on land gastropods infesting major field, vegetable and fruit crops in 12 villages (localities) representing four districts (counties) of Dakahlia governorate through the seasonal activity period of gastropod species during two successive growing seasons 2018/2019 and 2019/2020 revealed the occurrence of three land snail species and one slug species belonging to order: Stylommatophora. The snail species were, the glassy clover snail Monacha cartusiana (Muller) family: Hygromiidae, the brown garden (chocolate-band) snail Eobania vermiculata (Muller) family: Helicidae and the succineid snail Succinea sp., family: Succineidae, while the slug species was Deroceras sp., family: Agriolimacidae. The identified species varied in their incidence according to host plant, locality and season. In this respect, M. cartusiana snail has the upper hand, since it was detected in most of all surveyed localities infesting the majority of examined crops. It was more abundant on field and vegetable crops compared to fruit trees. E. vermiculata was found on all examined fruit crops. It was not detected on any of the studied field or vegetable crops at all surveyed localities. On contrary, the succineid snail Succinea sp. was found on field and vegetable only, it was not observed infesting fruit crops. On the other hand, the slug Deroceras sp. was found in certain localities infesting all examined crops except wheat, broad bean and potato. Population density of M. curtusiana differed from host plant to another and from locality to another. Among field and vegetable crops, Egyptian clover and lettuce gained the highest values while wheat and potato showed the lowest ones. Since, the highest number of this snail on Egyptian clover and lettuce were counted in Borg El-Nour village (Aga district) and Batra village (Talkha district) during 2018/2019 and 2019/2020 seasons with values 29.9, 25.6 (21.1, 19.5) and 27.7, 23.2 (24.4, 22.5) snails per 50 x 50cm2, respectively. Whereas, other identified gastropod species were found with relatively lower occurrence and population density on the infested crops. The seasonal population behavior of the predominant species, M. cartusiana was monitored on Egyptian clover and wheat during two successive seasons (2019/2020 and 2020/2021). It was found that population density increased during spring months as compared to low or moderate values during autumn and winter months.


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