Plant genetic resources are now confronted with a gradual extinction due to the widespread use of improved uniform varieties, socio-economic changes in agriculture, urbanization of farms mainly. Considering the worldwide trend of genetic erosion or genetic uniformity, emphasis should be placed on the collection and conservation of endangered plant genetic resources on the earth for future utilization. Since 1983, Japanese scientists have taken part in the international missions organized by the National Institute of Agrobiological Resources (NIAR) and International Board for Plant Genetic Resources (IBPGR) to collect plant genetic resources in South, Southeast and Central Asia. The missions collected a total of 6,549 samples of citrus, cereals, grain legumes, fruit trees, fodder crops and root crops. These international cooperative activities contribute to the collection and ex situ conservation of plant genetic resources in the respective countries. NIAR has also planned joint explorations with the scientists of Russia and the adjacent republics to collect plant genetic resources in the centers of diversity of Central Asia and the Middle and Near East proposed by N. I. Vavilov.
This report deals with the recent activities of the international explorations coordinated and funded by IBPGR, in particular in Pakistan in 1989 and 1991, and in Central Asia in 1992 and 1993, in addition to the national project of overseas exploration sponsored by the Ministry of Agriculture, Forestry and Fisheries of Japan.