Throughout the range of Prosopis (Leguminosae: Mimosoideae), seed predators, primarily beetles in the family Bruchidae, greatly reduce the numbers of viable seeds. The bruchids are very efficient in their feeding in Prosopis because they feed in seeds from the time they start to form in immature pods until after the pods have matured and fallen to the ground and, when the seeds are stored, they continue to feed until most of the seeds are destroyed. Thus, any study of the ecology or economic use of Prosopis should take into consideration the effects of seed predators upon species of Prosopis.
It has been suggested by several authors (e.g. Kingsolver et al. 1977, Johnson 1981c) that pods that are woody, sweet and nutritious (such as those of Prosopis) have evolved to attract large mammals that eat and digest the pods but do not digest the seeds. The seeds are dispersed and, by passing through the digestive tract of these large animals, are scarified and germinate more readily in the moist, fertile microhabitat of the animal droppings than seeds that are not eaten. In addition to being scarified and dispsersed in the guts of large animals, in the process of dispersal the seeds escape from the seed predators that attack them when they are near the parent plants. Thus, both the large mammals and the plant benefit. A wide variety of animals feed upon Prosopis pods in addition to insect seed predators. These include foxes and armadillos in South America and ants, cattle, rodents, sheep and goats in both North and South America (Kingsolver et al. 1977). Most of these can be considered as dispersal agents for Prosopis seeds.
Because seed predators are a very important component in the ecology of species of Prosopis, the data presented in this handbook were compiled to give biologists insight into the problems they might encounter with seed-infesting insects of Prosopis. Included are data on the biology of the Bruchidae but especially those that feed in Prosopis; descriptions of the damage caused to Prosopis by other species of seed-infesting insects; the control of Prosopis seed pests while the seeds are on the plants and in storage by chemical, biological and traditional means; a discussion of priority research needs; and the means of identifying the seed-infesting insects of Prosopis. Because species of Prosopis show much promise for development for fuelwood and fodder, this handbook could have a significant impact on the processes of conservation and domestication of Prosopis.
Both algarrobo (South America) and mesquite (North America) are used as common names for species of Prosopis. To avoid confusion, throughout this publication I will use the generic name Prosopis most often when referring to the plants.
