Departamento de Agronomia, Universidade de Brasilia 70910, Brasilia, Brasil
*Supported by a grant from the International Development Research Centre (IDRC), Ottawa Canada and the National Council for Research Development (Conselho Nacional de Desenvolvi-mento Cientifico e Tecnologico (CNPq), Brasilia, Brazil.
The author has travelled for 17 weeks (February 15-March 29, July 4-August 12, 1980; February 1-March 12, 1981) in nine Brazilian states distributed in two main areas: Northeastern Brazil in the states or Rio GraDde do Norte, Ceara Piaui, Maranhao, Pernambuco, Paraiba and Bahia; western-central Brazilian states of Goias and Mato Grosso do Sul. Seeds and/or cuttings were collected and planted in a living collection.
A total of about 726 introductions are now being grown at the Universidade do Brasilia. They are: M, caerulescens, M. glaziovii, M. dichotoma, M. pseudoglaziovii, M, epruinosa, M. heptaphylia, M. pohlii, M. grahamii, M. zenhtneri. M. reptans, M. sp- (undetermined), and a natural hybrid. Six thounsand seeds of the following spsc:es are being maintained until planting in next season: Manihot tripartita, M. gracilis, M. falcata, M. fruticujosa. M. longepetiolata, M. pentaphylla. M. alutacea, M. pruinosa, M. paviaefolia, M. slricta, M. salicifolia, M. purpurea-costatata, M, attenuata and M, tomentosa.
The geographical distribution of these species is reported.
Evaluation of the introductions in realtion to resistance to Xanthomonas maniholis and Coelosernus manihoti as well as the capacity to form tubers is presented. Seeds of these material have been made available to breeders at 1ITA, Nigeria and CIAT, Columbia.
