The Ecology of Bruchids Attacking Legumes (Pulses)

As editor of this volume I am not going to emphasize the economic im portance of the Bruchids of pulses, nor how necessary it is to know the conditions of infestation of crops in order to achieve an efficient protection; both points are testified by F.A.O.'s sponsorship, as well as of the International Organization for Biological Control. On the other hand I would like to stress the scientific interest of the study of 'domestic' bruchids. It raises questions which require that present basic entomological knowledge be extended. I am not going to review all questions raised but I will emphasize those I am most aware of. Some bruchid species have been able to colonize habitats differing totally; some differing in their latitude, and thus their basic periodicities; others differing in their degree of complexity (stocks of seeds): What are the respective roles played by polymorphism and plasticity in that exceptional capacity? What differences are there between the populations living on wild plants in dispersal areas and those living in stocks? What are the alterations brought about by the drastic selection pressures in populations having later colonized habitats ecologically similar to the original habitats? What factors determine the degree of specificity of trophic relationships, and the possibilities of extension of the niche? What influences are exerted by the other elements of the original bio cenoses upon the behavioural evolution of these species? Such are a few fundamental problems that can be tackled directly through

Klappentext

Proceedings of the International Symposium held at Tours, France, 16-19 April, 1980

Inhalt
Ecological problems arising from weevil infestation of food legumes.- Univoltine and multivoltine cycles: their significance.- The bean weevil populations from the Acanthoscelidesobtectus Say. group, living on wild or subspontaneous Phaseolus vulgaris L. and Phaseolus coccineus L. and on Phaseolus vulgaris L. cultivated in the Teportlan region state of Morelos Mexico.- Some ecological factors affecting diapause in adults of Acanthoscelidesobtectus from Mexican mountains.- Importance of allelochemics in plant insect relations: personal reminiscences.- The role of sense organs in the relations between bruchids and their host plants.- Relations of Acanthoscelides with their plant hosts.- First data on Bruchidae which attack the pods of legumes in Upper Volta, of which eight species are man consumed.- Role of allelochemics in the specialisation of trophic relations between bruchids and legumes.- Feeding, longevity and reproduction of adults of Acanthoscelidesobtectus Say in laboratory conditions.- Some data on the reproductive activity of Zabrotes subfasciatus in the laboratory.- Trophic relations and ecological status of the adults of Bruchus pisorum L. and allied field species of Bruchidae Coleoptera).- Evolution of spatial pattern of attacks by Acanthoscelides obtectus Say (Coleoptera: Bruchidae) of Phaseolus vulgaris L. pods in south west France.- Polymorphism and phase dimorphism in Callosobruchus.- Reproductive polymorphism of populations of Acanthoscelidesobtectus from different Colombian ecosystems.- Influence of the tegument of Phaesolus vulgaris seeds and of larval density on the development of Acanthoscelides obtectus Say.- Polymorphism and ecological reactions in Callosobruchus maculatus F. (Coleoptera, Bruchidae) in Upper Volta.- The use of resistantvarieties of cowpeas (Vigna unguiculata) to reduce losses due to post-harvest attack by Callosobruchus maculatus.- Bruchidae related to grain legumes in the Afrotropical area.- Distribution, ecology and importance of bruchids attacking grain legumes and pulses in Africa.- Observations on the ecology of Bruchidius atrolineatus Pic. and Callosobruchus maculatus F (Coleoptera, Bruchidae) in Niger.- Distribution and importance of bruchid attacks on different species of pulses consumed in the Near East.- The parasites of bruchids.- Conclusions and recommendations.