Survey and Seasonal Population Dynamics of Terrestrial Snails Infesting Some Fruit Trees and Ornamental Plants at Gharbia Governorate

Terrestrial gastropods are one of the most dangerous pests attacking field crops, vegetables, fruit trees and ornamental plants. Survey and population dynamics were carried out on land snails and slugs infesting certain fruit trees and ornamental plants in nine villages representing three districts at Gharbia governorate during their activity period from Janruary 2022 to April 2023. Four land snail species, and one land slug species were recorded. The snails were, Eobania vermiculata (Müller), Monacha cartusiana (Müller), Theba pisana (Müller), Succinea putris (Linnaeus) ,besides the slug, Deroceras reticulatum (Müller). M. cartusiana and E. vermiculata snails were the predominant species, since they were found on almost all hosts and localities with moderate or high levels of infestation .While T. pisana snail showed less occurrence with moderate to high infestation levels in the three localities of Zefta district .However, S. putris and D. reticulatum were found with limited distribution in one or two localities of Al-Santa district with low level of infestation. The population dynamics of E.vermiculata, M.cartusiana, and T.pisana snails were studied on navel orange trees in Kafr Shobra Al-Yaman village, Zefta district, Gharbia governorate over two growing seasons (2021/2022 and 2022/2023). The active snails first appeared in November, with slight increases in numbers during the winter months of December and January. A noticable population increase occurred in February, peaking in April, followed by a decline in May. In general, the seasonal abundance of E. vermiculata, M. cartusiana and T. pisana snails increased during spring compared to winter and autumn.