A survey of the mite fauna associated with Amaranthus cruentus L. (amaranth), Solanum macrocarpon L. (Gboma) and S. aethiopicum L. (African eggplant), three major indigenous vegetables produced in Benin, was carried out from August to October 2004 both at IITA-Benin station and on a vegetable farm at Togba in Abomey-Calavi area. Thirty-three mite species belonging to 12 families were found on the three vegetables. These species included phytophagous mites, predatory mites of the family Phytoseiidae, and another group whose feeding habits were not clear. The following phytophagous mites were found: Tetranychus urticae Koch and T. ludeni Zacher, in the family Tetranychidae; Polyphagotarsonemus latus (Banks) and another unidentified mite species, in the family Tarsonemidae. The two Tetranychus species were present on all three vegetables whereas tarsonemids were found only on the two solanaceous plants. Polyphagotarsonemus latus was the most dominant pest during the course of the experiments. It is the major mite pest on solanaceous plants, especially on Gboma in vegetable farms, where broad-spectrum pesticides harmful to natural enemies are used. The phytoseiids group was the most diversified with 16 species out of the 33 identified and more predominant in IITA plots where no pesticides were applied, compared to Togba plots where pesticides were regularly applied on nearby plots. They seem to better control P. latus on Gboma than on African eggplant. Other mites identified on the three vegetables belong to the following families: Acaridae, Tydeidae, Erythraeidae, Cunaxidae, Anystidae, Ascidae, Bdellidae, Uropodidae and Oribatidae.

The damage potential of the spider mite Tetranychus ludeni Zacher was studied on 20–65-day-old seedlings of four eggplant Solanum melongena varieties: Madurai (MDU1), Coimbatore (CO1), Annamalai and Panruti at introduction levels of 2, 5, 10 and 15 mites/leaf. The average seedling mortality among varieties was lowest at the introduction level of two mites and maximum at the introduction level of 15 mites/leaf. The overall seedling mortality was 23% when the four levels of mite population were introduced on 20-day-old seedlings, and only 14% on 30-day-old seedlings. Among the different varieties, the MDU1 seedlings recorded higher mortality (1.6%) and Panruti the lowest (0.3%). The percentage losses in total plant height, number of leaves, number of flowers and fruits and fruit weight due to mite attack were highest (37–50%) in MDU1 and lowest (7–11%) in the variety Panruti. The other two varieties CO1 and Annamalai were found to be intermediate between Panruti and MDU1. The inoculated mites at different levels multiplied greatly on the variety MDU1 followed by CO1, Annamalai and Panruti. The extent of damage was higher in 35-day-old plants, when mites were introduced on 35- and 65-day-old seedlings. Therefore, the variety Panruti is recommended for cultivation in the study area in view of its resistance to T. ludeni.