Multi–gene‐pool Surveys in Areas with Rapid Genetic Erosion: An Example from the Aïr Mountains, Northern Niger

Abstract

Abstract: A survey to sample and document wild and cultivated plants with crop and forage genetic resources was carried out in the Aïr Mountains of northern Niger in 1984, 1985, and 1986. This ecogeographical survey was begun in the 1984 drought after considerable desertification had already occurred. Over the last century in this area, there has been progressive alteration and loss of habitat and populations, with probable genetic erosion. The focus was on wild and weedy species in the following gene pools: Pennisetum, Sorghum, Olea, Andropogon, Cenchrus, Brachiaria, Eragrostis, Panicum, Setaria, Acacia, Ziziphus, and Grewia; and on crops from irrigated gardens, including pearl millet, sorghum, and barley. Due to the high degree of environmental heterogeneity and the loss of habitat, relativity small numbers of individuals and clumps were identified a significant portion were probably part of previously contiguous occurrences. In this type of setting, surveys of rapidly diminishing crop and forage genetic resources are especially needed A basis for identifying strategies for sampling and monitoring as species ecology and successional and cultural factors is outlined.