Open    Access



Effects of Aqueous Extracts of Seeds of Peganum harmala L. (zygophyllaceae) on 5th Stage Larvae Locusta migratoria cinerascens (Fabricius, 1781) (Orthoptera: Oedipodinae)



Author(s)

Abdelmadjid Benzara, Abdellah Ben Abdelkrim and Ouassila Khalfi-Habes

Full-Text PDF XML     330 Views

DOI:10.17265/1934-7391/2013.02.009

Agronomic National Institute, El Harrach, Algiers 16200, Algeria

The study has for objective the determination of the efficiency of the aqueous extracts from seeds of Peganum harmala L. on the mortality of the larvas of 5th stage and on the fertility of the female adults of Locusta migratoria cinerascens. For that purpose, a breeding of locusts was realized in the conditions of laboratories. At hatching, the larvae are fed daily basis lawn Stenotaphrum americanum and a protein supplement of wheat bran. The extraction of the aqueous extract of the seeds of P. harmala is done after maceration in the ethanol, under magnetic stirring using a rotavapor. To determine larval mortality L5, two modes of treatment have been made, one by contact and another by ingestion, using for both treatment 4 doses in a geometric progression, 0.03 mg/mL, 0.06 mg/mL, 0.12 mg/mL and 24 mg/mL. The results showed that the mortality for the doses of 0.12 mg/mL and 0.24 mg/mL, reaches respectively 40% and 60% on the 3rd day, as well for the treatment by contact as by ingestion. But the LD50 for ingestion treatment is lower. It is 0.19 mg/mL contrary to that of the contact treatment (0.19 mg/mL). The larvae that survived the treatment by ingestion, have suffered morphological changes as well as physiological which consist of a deformation of the wings, delayed of the larval molt, of 6 days, blocking the fledging, the change of the pigmentation as well as an extension of the preoviposition. Fertility was also affected and females lay only twice, a small number of eggs, unlike untreated females which come to lay 3 times with an average of 62.7 eggs/female at first spawning against 50 eggs for the females treated.

Locusta migratoria cinerascens, aqueous extracts, Peganum harmala, lethal dose, fecundity.