Dans l'objectif de trouver un alternatif à l'endosulfan, l'efficacité du profenofos et de l'endosulfan a été étudié dans un dispositif de bloc aléatoire complet en station et en milieu réel. Sur station, le profenofos assure un contrôle, équivalent et parfois significativement supérieur (p < 0,001) à l'endosulfan, des populations des ravageurs comme Helicoverpa armigera, Earias spp, Pectinophora gossypiella, Cryptophlebia leucotreta. Le Fanga 500 EC (profenofos 750 g/ha) a été significativement supérieur (p < 0,05) à Callisulfan 350 EC (endosulfan 700 g/ha) pour le contrôle des populations de Aphis gossypii, Pectinophora gossypiella et Earias spp. Il en résulte une production de capsules vertes saines qui montre que le Calfos 500 EC (profenofos 750 g/ha) est équivalent aux différentes formulations d'endosulfan testées et parfois significativement meilleur (p < 0,01) au Thiofanex 350 EC (endosulfan 700 g/ha). A la récolte du coton graine, le profenofos procure un rendement significativement supérieur (p < 0,05) à l'endosulfan. En milieu paysan, aucune différence significative (p > 0,05) n'a été observée entre le Calfos 500 EC (profenofos 750 g/ha) et le Callisulfan 350 EC (endosulfan 700 g/ha) à la récolte du coton graine. Le profenofos peut être appliqué comme un alternatif à l'endosulfan en culture cotonnière au Bénin.

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Preservation of predators of crop pests is fundamental in management of crop pests. Botanical insecticides are increasingly used because of their limited effects on the pest auxiliaries. Oil from the seed of Thevetia peruviana and an bio-insecticide from Azadirachta indica called Top bio, were tested at Gobe in center of Benin for the assessment of their effects on predators of crop pests comparing two doses (1% and 2%) of Thevetia oil and two doses (2 l/ha and 3 l/ha) of Top bio to, a reference bio-pesticide called Agri-bio-pesticide at 1 l/ha and to a control treatment. A Fisher design with 6 objects and 4 repetitions were used. Linear and generalised linear mixed and fixed effects models were used to investigate the effect of objects on predators of crop pests enumerated on 30 plants per plot. The cotton plots treated with 1% of Thevetia The Top bio did not significantly reduce the number of spiders compared to the Agri-Bio-Pesticide and the control treatment. Additionally, the two doses of Thevetia oil did not significantly reduce the number of Chrysopes compared to the untreated control. For the most part, biopesticides did not significantly reduce the number of ladybugs, ants, Phonoctonus and mantis. These predators of crop pests can be effectively used like biocontrol agents in an integrated management strategy of crop pests using these biopesticides.

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This study aims to evaluate the larvicidal effect of three vegetable oils: Tephrosia purpurea, Ricinus communis, Thevetia neriifolia, and cashew balm in the management of Plutella xylostella L. 1758 (Lepidoptere, plutellidae) pest insects of cabbage in the laboratory. The efficacy of the extracts has been compared to that of a synthetic insecticide (Lambda cyalothrin) and that of a 100%, 75%, 50%, 25% and 10% while in the second, the same products were tested on the L2 stage of the same insect with the doses of 50%, 25%, 10%, 5%, 3%, 2% and 1% compared to the reference control Lambda cyalothrin at the doses of 10%, 5%, 3 %, 2%, 1%, 0.5%. The mortalities were read 24 hours after exposure until the ninth day. The device used for biological tests is a completely randomized block. Abbott's formula has been used to correct mortality rates for treated insects. The variables measured are the mortality rate, the formation of pupae and the emergence of adults. These variables are subjected to an analysis of variance with the XLSTAT software version 2019. The LD 50 for eight days were determined according to the Cox regression method of determining the dose corresponding to a proportion. The results showed that vegetable oils and cashew balm are the promising species in the management of dose-dependent P. xylostella. For the first experiment, the mortality rates of L3 larvae of P. xylostella were not significantly different between the 25% application doses of Topbio and T. purpurea. Mortalities ranging from 100% were recorded with the doses of 100%, 75%, 50% and 25% of all the products used on the L2 and L3 stages. During the second experiment, 100% mortality was recorded at an application dose of 10% respectively for Topbio, T. purpurea, CNSL, and R. communis. No significant difference was recorded at the 5% threshold between the 10% doses of T. purpurea and 3% of the reference control Lambda cyalothrin. Witnesses recorded the highest rate of pupae and adults. These two parameters were a function of the dose. For all the products used, whatever the larval stage of P. xylostella, the effect / dose response was significant. Cashew balm and the three vegetable oils are positioned as an alternative to synthetic pesticides that can be used in market gardening.