This study was conducted under field conditions at Quessna district, Monufya Governorate during two successive seasons 2009 and 2010. The present work aimed to throw light on the effect of climatic factors temperature degree and relative humidity on land snails population and their damage to some stand crops( Clover, Lettuce and Navel orange ). The obtained results could be summarized as follows:-1)-Monacha cartusiana (Muller) and Eobania vermiculata (Muller) were only observed infesting Clover, Lettuce and Navel orange during the experimental period. Also, the the ecological studies indicated that M. cartusiana was found in abundance on Clover and Lettuce both, meanwhile Navel orange had E. vemiculata more than the another, snail. 2) -Clover was the most attractive to M. cartusiana followed by Lettuce and Navel orange, whereas, the last crop was the most attractive to E. vermaculata than Clover and Lettuce. 3)-The land snails population was fluctuated during the experimental crop life from month to month due to variations in temperature degree and relative humidity.The results indicate that there is a positive correlation between snail population and the relative humidity , meanwhile it is negative with the temperature degree. The highest population (115.5 individuals) was recorded in February (16 C &59.9 % R.H.) and the lowest one (33 individuals) in May (29 C & 54.7% R.H.). 4)-The obtained results showed that the highest infestation of land snails (0.89%, 0.83% and 0.64%) and the lowest (0.45%, 0.49% and 0.19%) for Clover, Lettuce and Navel orange were recorded in March (18.6C & 59.7% R.H.)and in May (29 C & 54.7% R.H.), respectively. 5)-The obtained results proved that the most suitable geographical conditions to increase the population of land snails are low temperature degree and height relative humidity. Also, it is added that, there is a positive correlation between population of land snails and their damage to the three tested crops.
Laboratory study was carried out to show the effect of daily oral administration 1 /4 LD50 (500 mg/kg b.w.) of herbicide Butachlor (Machete) after 1, 2, 3 and 4 weeks post treatments on some organs weight and histological changing of the climbing rat Rattus rattus frugivorous. Concerning the histological changes in liver, there was focal mononuclear leucocytes the results of this study cleared that there is a significant decrease in body weight of the treated animal comparing to the untreated ones during the period of exp. On contrast weight of the liver, kidney, heart and lungs that increased significantly and caused inflammatory cells infiltration, kÜpffer cells proliferation and hemosiderin pigments in between the degenerated hepatocytes. In addition dilation in the central veins, portal veins and sinusoids were observed. Also, AST, ALT enzymes and total protein were changed in plasma of roof rat, Rattus rattus after oral administration 1 /4 LD50 Butachlor herbicide daily for one month were affected. An increase in AST, ALT and total protein level at all tested periods, except at 4 th weak total protein did not significant changed compared with control.
MATERIALS AND METHODES
Chemical compound:Butachlor (Machete) herbicide was obtained from Monsanto Co. Chemical name:N-butoxymethyl-2-chloro-2, 6-dimethyl acetanilide. LD50 for rat 2000 mg/kg body weight.
Background
The investigation aimed to show the effect of two concentrations of (Protecto 9.4%) commercial formulation of Bacillus thuringiensis kurstaki (Bt) on some biochemical changes of the land snail Monacha cartusiana at three different experimental periods (24, 48 and 72 h). Also, some histobiological altrations of the snail at a lethal experimental period of 96 h were studied.
Results
Pathogenicity effect of two sub-lethal concentrations of biopesticide Protecto; LC20 (6.72 × 106 IU/mg) and LC40 (17.28 × 106 IU/mg) were studied on the land snail M. cartusiana at 3 different exposure periods (24, 48, and 72 h). Some biochemical parameters such as Alkaline phosphatase (ALP), Alanine amino transaminase (ALT), Aspartate amino transaminase (AST), and Total protein (TP) were investigated. These observations cleared that; a significant elevation of ALP, ALT, and AST increased with increasing the sub-lethal concentration of protecto (LC20 and LC40) against the exposed snail. Also, the activity of enzymes significantly increased with increasing the time of exposure (24, 48, and 72 h), respectively. Conversely, the level of TP in the snail was significantly decreased under pathogenic exposure for both (LC20 and LC40) concentrations of Protecto at the same three treated periods (24, 48 and 72 h). The histbiological examinations at LC20 and LC40 for the exposure period 96 h, showed that the digestive gland with vacuolated degenerated, ruptured digestive cells and hemocyte infiltration. Moreover, the foot was observed with necrotic changes, vacuolated connective tissue, as well as, deformation in muscle fiber, and rupture the outer layer.
Conclusions
Final results showed that protecto B. thuringiensis had a pathogenic effect on land snail enzymatic activities and histbiological structures of land snail.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.