In order to control insects it is necessary to know as much as possible about their life cycles so control measures can be timed to coincide with their most vulnerable stages. Additionally, the amount and kind of damage they do and the effects of their natural enemies on them should also be known. Therefore, the author believes the research that should be given the highest priority is to study intensively the life histories and ecology of the seed-feeding insects of Prosopis (Table 8 page 48). Model studies for this research are those of Glendening and Paulsen (1955), Swier (1974) Pfaffenberger and Johnson (1976), Koch and Campos (1978) and Conway (1980). Some of the techniques used and ecological factors that have been found to be of value and which should be taken into consideration when examining the relationships between seed-feeding insects and Prosopis are: collect many samples of seeds from Prosopis plants and from the ground beneath the plants, collect from broad geographical areas, place the seed samples into suitable escape-proof containers in a laboratory, allow adult bruchids and other insects to emerge, dissect the seed and pod to determine the location of the pupal chamber, determine the path of the larva through the seed and pod, the number of seeds fed upon, the point of entry of larvae through the pod and seed coat, the sites where eggs were laid, the means of attachment of the egg to the pod, size of seeds and size of insects, percent of seeds fed upon by each bruchid species, the number of hosts per species of bruchid, the number of generations of bruchids and their parasites per year, the total number of days during which the beetles emerged from culture, the various behavioural patterns of bruchids (for example, whether larvae enter a pod directly or crawl to a crack or crevice before entering; whether the larva spins a cocoon or glues seeds together for a pupal chamber; whether females lay eggs on pods on trees or on pods or exposed seeds on the ground, etc.). Plant characteristics that should be recorded are whether the pods are partially dehiscent or indehiscent, the thickness of the pod valves, the size and shape of the pods and seeds, the number of seeds per fruit, and any other unique characteristics of the seeds or fruits (for example, hairs on the pod valves, woody valves, whether there is a sticky pulp between the seeds and pod valves, etc.).
In the arid and semi-arid regions of the New World, studies in Mexico, Peru and Chile probably should be given the highest priority.
Another high priority research effort is to establish methods of controlling seed-infesting insects during the pre-harvest and storage phases (Table 8). Initially this would probably include only studies with synthetic organic insecticides but long-term studies should include traditional control (Table 6) and biological control (Table 7).
Of a slightly lower priority is to establish host preferences of seed-infesting insects of Prosopis, to determine their ability to move from one species of Prosopis to another (or from other plant species to Prosopis), and to classify the insects (numbers 3, 4, 5 in Table 8). These would need to be done in conjunction with the studies of life histories (number 1 in Table 8).
Long-range studies should include development of programmes of biological control, traditional methods of control and Integrated Pest Management.
