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)...

Using data on the distributions of disease and pest resistance among wheat varieties, this paper reports theoretical and empirical findings concerning the efficient management of a gene bank and the optimal size of a collection.

A theoretical model is developed and applied to the search for disease and pest resistance in ex situ collections of wheat genetic resources, employing actual data on frequency distributions, disease losses, and search costs. Experiments developed from case studies clarify several misperceptions...

Many developing countries pursue policies that treat large and small firms differently. For example, large firms may be subject to a value added tax while small firms are explicitly exempted. Moreover, governments often find it impractical to collect taxes from the smallest enterprises; this may...

This study asks whether the diffusion of modern varieties has affected the yield stability of wheat and maize production in developing countries between 1960 and 2004. The data suggest strongly that, over the past forty-plus years, there has been a striking decline in the relative variability of...

This chapter describes the impact of national agricultural research systems on the unfolding of the Green Revolution in four regions: Asia, Latin America, the Middle East and North Africa, and Sub-Saharan Africa. Although international institutions contributed much of the research that led to...

Agriculture is the largest sector in most sub-Saharan economies in terms of employment, and it plays an important role in supplying food and export earnings.  Rural poverty rates remain high, and labor productivity is strikingly low.  This paper asks how these factors shape the role of...

According to national accounts data, value added per worker is much higher in the nonagricultural sector than in agriculture in the typical country, particularly in developing countries. Taken at face value, this “agricultural productivity gap†suggests that labor is greatly...

According to national accounts data for developing countries, value added per worker is on average four times higher in the non-agriculture sector than in agriculture. Taken at face value this "agricultural productivity gap" suggests that labor is greatly misallocated across sectors in the...