Assessing the molluscicidal and biochemical activities of New-Fort®, an inorganic fertilizer against Theba pisana snails.

Terrestrial snails are a significant issue in agricultural production worldwide. The use of nitrogen - phosphorus - potassium (NPK) based fertilizers played an important role in meeting the food demand throughout the world, so its effectiveness against land snails needs to be investigated. This study was conducted to evaluate toxic lethal effect of New-Fort®, an inorganic NPK based fertilizer, in the field for 3, 7 and 10 days and in the laboratory for 24, 48 and 72 h against Theba pisana snails. Also, the impact of its sub-lethal doses (1/10, 1/5, 1/4 and 1/2 of 48 h-LD) on biochemical parameters were determined under laboratory conditions. The results showed that the snails percent reduction in the field were 21.4, 61.0 and 80.0 % after 10 days' application of quarter, half and one field rate and the values of LD in the laboratory were 4.94, 4.56 and 4.24 mg/g b.w at 24, 48 and 72 h, respectively. New-Fort® sub-lethal doses caused a significant inhibition in catalase, γ-glutamyl transferase and acetylcholinesterase activities. It also elicited a significant elevation in glutathione S-transferase activity post exposure to 1/10 and 1/5 of LD, whereas an opposite effect was occurred after exposure to 1/4 and 1/2 of LD. Lipid peroxidation level was reduced in snails treated with 1/10 and 1/5 of LD, whereas it increased in 1/4 and 1/2 of LD- treated snails. Moreover, a significant inhibition in alkaline phosphatase activity at all tested doses, with the exception of 1/2 of LD was observed. An increase in alanine aminotransferase and aspartate aminotransferase activities were occurred after all tested doses exposure. Our findings highlighted on how biochemical changes can be exploited to better understand the mechanisms underlying New-Fort® fertilizer toxicity against the land snail, T. pisana, as well as how to benefit from NPK fertilizers application in snail control.