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This review provides evidence on the genetic diversity, chemical constituents, and ecotoxicology of Mesosphaerum suaveolens' essential oil. It emphasizes the agricultural benefits such as crop protection effectiveness of the plant and highlights the existing knowledge gaps and research perspectives to promote its utilization in agriculture. A systematic and extensive review of the literature was done and all pertinent full-text articles and abstracts were analyzed and incorporated into the review. Mesosphaerum suaveolens is used traditionally in pharmacology to treat several diseases such as malaria, constipation, stomach problems, and renal inflammation. It also treats cramps, digestive infections, headaches, and skin infections. To date, very few studies have been conducted worldwide about its genetic diversity. These studies highlighted three morphological variants, the blue-flowering, the white-flowering, and the lightpurple flowering M. suaveolens. Its wide biological actions may be attributed to the numerous groups of chemical constituents in its essential oil including monoterpenes, sesquiterpenes, and diterpenes. Biological studies highlighted evidence of M. suaveolens being used as an antifungal, bactericidal, antimicrobial, insecticidal, and repellent plant. The essential oil extracted from M. suaveolens showed significant potential for the control of agricultural pests such as Sitiophilus zeamais, Helicoverpa armigera and Helminthosporium oryzae. M. suaveolens is commonly used worldwide as a pesticidal plant in healthcare, agriculture, and food preservation. However, there is a lack of studies concerning the toxicity and effectiveness of isolated potent phytotoxic substances, the efficacy screening in the field, the genetic diversity, the essential oil yield, and productivity. Consequently, further studies are required to fill the knowledge gaps. [ABSTRACT FROM AUTHOR]

Spider plant (Gynandropsis gynandra) is a traditional leafy vegetable with the potential to address malnutrition and food insecurity in Africa. To date, little is known about farmers' perception and knowledge of pests and diseases affecting this plant species and their management practices in Africa. This study aimed at assessing farmers' perceptions and knowledge of insect pests in Benin in order to develop a sustainable pest management scheme for spider plant cultivation. One hundred and eighty (180) farmers were interviewed using a semi-structured questionnaire, group discussions, and direct field observations through ethno-entomological surveys in August and September 2017. The results from the survey indicated insect pests as the main constraints for spider plant cultivation in southern Benin. Three groups of insect pests were recorded on spider plant; these included lepidopteran larvae [pod borer (Hellula undalis)], aphids (Lipaphis erysimi), and green vegetable bug (Acrosternum millieri). This indicated that farmers had a good knowledge of insect pests which varied significantly across municipalities. The result of the ordered probit regression showed that among all socio-economic variables, only "education level" and "farm size" had respectively negative and positive significant relationships with farmers' knowledge. Although most farmers did not actually control insect pests on spider plant, some of them (15.05% at Djakotomey) used chemical pesticides. Based on our results, we propose that an Integrated Pest Management scheme including the use of botanical pesticides and resistant varieties combined with good agronomic practices should be developed and shared with farmers through participatory farmers' field schools. [ABSTRACT FROM AUTHOR]

In Benin, synthetic insecticides are the main pest control option used by farmers to protect and enhance their production. However, failures to control the target pests are often observed after application and may be related to agricultural practices or insecticide quality. The present work was designed to assess a rapid, simple, and reliable analytical method for detecting and quantifying the most commonly used insecticides (λ-cyhalothrin and acetamiprid) in Benin. The analytical standard technical grade separation was performed by gradient reversed-phase high-performance liquid chromatography on a C18 stationary-phase column. The mobile phase consisted of a mixture of acetonitrile/water using a gradient flow. The flow rates were 1 and 1.4 mL·min−1 for λ-cyhalothrin and acetamiprid, respectively. The analysis times were 15 and 20 min, with retention times of 2.35 and 7.94 min for λ-cyhalothrin and acetamiprid, respectively. Results reveal that most of the surveyed farmers were not educated (70% < Primary School Certificate) and were men (95%). Of the main insecticides applied by farmers, λ-cyhalothrin and acetamiprid were found to be the most technical-grade ones. Furthermore, the analysis of insecticides showed that the concentrations obtained in our study often differed from the ones mentioned on insecticide labels. The proposed method is useful for quantifying insecticides in various technical and commercial formulations with little interference from additives. [ABSTRACT FROM AUTHOR]

Various plant species contain biocidal and/or semiochemical components. These can be used for managing insect pests, in order to reduce the use of synthetic pesticides and to improve the quality of vegetable crops. This study was conducted to assess the effect of repellent plants Ocimum gratissimum L. and Ocimum basilicum L. on aphids Aphis craccivora Koch, Aphis fabae Scopoli and Myzus persicae Sulzer when they are associated with Amaranthus hybridus L. plants. The results have shown that in the two approaches tested—Ocimum sp. plants surrounded by A. hybridus plants and the dual-choice test—the number of aphids on the A. hybridus plant associated with either O. gratissimum or O. basilicum was significantly less significant compared to the A. hybridus alone. This first study on the association between A. hybridus and Ocimum spp. shows that the Ocimum species might be used as an alternative method for controlling aphids in order to avoid the use of synthetic pesticides on Amaranthus. The ability of Ocimum spp. to repel pests can make it an important companion plant for farmers, because those plants can not only be used to control pests, but they can also be harvested, providing a direct economic return. [ABSTRACT FROM AUTHOR]