الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
 |  | from | 174 |  |  |
| | | from | 174 | | |
Abstract
The present work was carried out to study ecology, biology and control of some terrestrial molluscs infesting some field and vegetable crops at Sharkia and Ismailia Governorates. Ecological studies indicate that five species belonging to three families of order: Stylommatophora were identified on field and vegetables crops. Survey revealed that the identified species varied in their incidence and level of infestation according to locality and host plant type. Monacha cartusiana has the upper hand on snails incidence compared to other species, it was recorded in all surveyed localities. The population dynamics of M. cartusiana throughout two successive seasons on some vegetable crops indicated that strawberry harbored highest numbers followed by tomato, while watermelon was the lowest one in this respect. On the other hand, frequency occurrence and population density of land gastropods infesting field crops were differed from district to another and from host plant to another . Therefore, importance value of terrestrial mollusca species can be arranged descendingly at Sharkia as follows: M. cartusiana > Succinia putris > Deroceras reticulatum and while, parallel values at Ismailia were : M. cartusiana > S. putris > D. reticulatum > Deroceras leave> Cochlicella acuta. Daily activity of M. cartusiana on strawberry under field conditions showed that the main active period in all seasons was during the night hours. The time between 2 to 6 O’clock represented the period of the highest activity. On the other hand, food consumption of the snail, M. cartusiana under laboratory conditions showed the highest values of feeding damage on kidney bean> watermelon > strawberry red fruit> tomato> strawberry leaf> strawberry green fruit. The breeding season of the amber snail Succinea putris lasted 3.5 months started from December 2007 to mid March 2008. Numbers of clutches and eggs significantly changed through the breeding season. More clutches were laid during January and February compared to December month. Finally, experiments of evaluating molluscidal activity of four pesticides under laboratory and field conditions indicated that methomyl proved to be the most effective compound followed by predalil, bentazon, while the biofar was the least effective one. The tested solar oil emulsion, it showed to be with weak effective on land snail M. cartusiana under field condition when used in irrigation water, while it gave 100% mortality for eggs. The fermentation time of bait could be arranged descendingly according to their effect as follows: 6hr, 24hr, 12hr, while the fresh bait showed the least effective one