This paper discusses the centers of origin and diversity for bread wheat; sketches historical patterns in the sources and use of wheat genetic resources in modern plant breeding; identifies and compares indicators of genetic diversity used by social and biological scientists; reviews the...

Experimental results and farmer surveys in a Mexican community indicate that farmers� seed selection practices protect the phenological integrity of their maize varieties as they define them, despite numerous factors contributing to genetic instability. Analysis of morphological and genetic...

This study records the use of hybrid maize seed and fertilizer by small-scale farmers in Malawi, as well as their opinions about these inputs, from 1989-90 through 1996-97. Its main purpose is to determine whether the principal constraint to smallholders� use of maize hybrids is the...

Identifying the appropriate germplasm to be improved is a key component of any participatory breeding effort because of its implications for impacts on social welfare and genetic diversity. This paper describes a method developed to select a subset of 17 populations for a participatory breeding...

Four environments with contrasting potential for agricultural productivity and infrastructure development were identified in Guanajuato State, Mexico, to test hypotheses about the relationship of maize biological diversity to the region's potential for agricultural productivity and...

The principal advantage of in situ conservation is that it allows adaptive evolutionary processes to continue in the species that are being conserved. For a cultivated crop species, in situ conservation involves farmers' management of their own genetic resources even as the farmers themselves...

This study makes use of data on wheat production in the Punjab of Pakistan from 1979 to 1985 to 1) examine patterns of varietal diversity in farmers' fields both at the regional and district levels and 2) identify how and in what ways genetic resources have contributed to wheat productivity and...

This paper develops a theoretical model for analyzing gene bank management decisions regarding the search for traits of economic value in ex situ collections of wheat. The model is applied to data on the probability of finding useful sources of resistance to Russian wheat aphid (Diuraphis noxia)...