Molluscicidal activity of Nerium indicum bark

Abstract

The molluscicidal activity of Nerium indicum bark against Lymnaea acuminata snails was studied. The toxicity of different bark preparations was both time and dose dependent. The 24-h LC 50 of the lyophilized aqueous extract of bark was 34.5 mg/l whereas that of lyophilized boiled water extract was 42.5 mg/l. Low concentrations of vacuum-dried ethanolic extract (24-h LC 50 : 4.9 mg/l) and purified bark (24-h LC 50 : 0.87 mg/l) were effective in killing the test snails.

Effect of Single and Binary Combinations of Plant-Derived Molluscicides on Reproduction and Survival of the Snail Achatina fulica

“…Water was sprayed at a regular intervals to maintain suitable moisture for the snails. Snails were exposed to sublethal concentrations (20% and 60% of LC 50 /24 h) of different plant-derived molluscicides, A. indica oil (AI), C. deodara oil (CD, supplied by Indian Herbs, Saharanpur), A. sativum bulb powder (AS), and N. indicum bark powder (NI, prepared using the method of Singh and Singh 1998) and binary combinations (1:1) of AS ϩ CD and CD ϩ AI oils. AI and CD oils singly and in binary combinations were emulsified in water by using nonionic emulsifier Shnehakshar (Singh and Singh 1997a).…”

Evaluation of indigenous plant extracts against larvae of Culex quinquefasciatus Say (Diptera: Culicidae)

“…The ethanolic and acetone extracts of Nerium indicum and Thuja orientelis have been studied against III instar larvae of A. stephensi and C. quinquefasciatus ; the aqueous, lyophilized boiled water and ethanolic bark extracts of N. indicum was tested for the toxic effect against Lymnaea acuminata (Singh and Singh 1998); the toxic effects of crude extract was tested against Tribolium castaneum (Naqvi and Parveen 1991). Laboratory evaluation revealed that the treatment of larvae of Aedes aegypti and C. quinquefasciatus with ethanol and aqueous extract of Pongamia glabra seed kernels significantly increased the larval mortality and developmental period proportionately with increase in the extract concentrations (Sagar and Sehgal 1996;Sagar et al 1999).…”

Toxic effect of single and binary treatments of synthetic and plant‐derived molluscicides against Achatina fulica

“…It has been reported that C. deodara oil, A. sativum bulb powder and N. indicum bark are potent molluscicides. 3,4,10 The active moieties responsible for molluscicidal activity are oleandrin in N. indicum and allicin in A. sativum.…”

“…5 ( sprayed with different concentrations (%) of synthetic molluscicides (phorate, from All India Medical Company; carbaryl, from Union Carbide India Ltd; cypermethrin, from Bharat Pulverizing Mills Pvt. Ltd, India; Snail Kill (metaldehyde), from Pesticides India) and molluscicides derived from plant products (Cedrus deodara oil and Azadirachta indica oil were supplied by Indian Herbs, Saharanpur; Allium sativum powder and Nerium indicum bark powder were prepared using the method of Singh and Singh 3,4 ) and binary combinations (1 : 1) of plant products (Table 2). Single spraying with 1 ml of synthetic or plant-derived products was carried out directly on each snail between 8 p.m. and 10 p.m. Mortality was recorded 24 h for the duration of the 96-h exposure period.…”