The Contribution of Genetic Resources and Diversity to Wheat Productivity: A Case from the Punjab of Pakistan

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 yield stability-important considerations to farmers and national authorities where wheat is a staple food crop. Five indicators are used to describe the system of wheat genetic resource use and diversity in farmers' fields. The contribution of farmers' previous selections is expressed as the number of different landraces appearing in the pedigree of a cultivar . The contribution of scientific breeding efforts is expressed as the number of parental combination appearing in a cultivar's pedigree. The diversity of wheat varieties in a geographical area, as related to productivity, is captured by measures of area concentration (diversity in space) and age of varieties (diversity in time). Finally, the relative dissimilarity of cultivars grown in a geographical area is measured using a distance indicator constructed from genealogical information. Disaggregated analysis at the district level demonstrates how diversity patterns are influenced by the production environment and by possible differences in the availability of suitable varieties. The study finds no indication that modern plant breeding technologies have reduced diversity among the wheats grown in the districts of the Punjab of Pakistan during the study period, although brief. Analysis of the genealogical background of the varieties grown by farmers reveals patterns of greater use of genetic resources and dissimilarity of parentage. For some factors related to genetic resource use and diversity, there are large differences between production environments (specifically, irrigated and rainfed areas) and individual districts, which suggest that efforts to increase genetic diversity in farmers' fields will require policy instruments tailored to the individual circumstances of each production environment. Econometric results suggest that greater genealogical dissimilarity and higher rates of varietal replacement are likely to have positive payoffs relative to aggregate yield stability, while in areas where production constraints inhibit farmers' ability to exploit the yield potential of their varieties, better production management is likely to have greater yield enhancing effects than the varietal attributes related to diversity.Crop Production/Industries,

Modeling Routes of Chronic Wasting Disease Transmission: Environmental Prion Persistence Promotes Deer Population Decline and Extinction

Chronic wasting disease (CWD) is a fatal disease of deer, elk, and moose transmitted through direct, animal-to-animal contact, and indirectly, via environmental contamination. Considerable attention has been paid to modeling direct transmission, but despite the fact that CWD prions can remain infectious in the environment for years, relatively little information exists about the potential effects of indirect transmission on CWD dynamics. In the present study, we use simulation models to demonstrate how indirect transmission and the duration of environmental prion persistence may affect epidemics of CWD and populations of North American deer. Existing data from Colorado, Wyoming, and Wisconsin's CWD epidemics were used to define plausible short-term outcomes and associated parameter spaces. Resulting long-term outcomes range from relatively low disease prevalence and limited host-population decline to host-population collapse and extinction. Our models suggest that disease prevalence and the severity of population decline is driven by the duration that prions remain infectious in the environment. Despite relatively low epidemic growth rates, the basic reproductive number, R0, may be much larger than expected under the direct-transmission paradigm because the infectious period can vastly exceed the host's life span. High prion persistence is expected to lead to an increasing environmental pool of prions during the early phases (i.e. approximately during the first 50 years) of the epidemic. As a consequence, over this period of time, disease dynamics will become more heavily influenced by indirect transmission, which may explain some of the observed regional differences in age and sex-specific disease patterns. This suggests management interventions, such as culling or vaccination, will become increasingly less effective as CWD epidemics progress

PUBLIC SECTOR PLANT BREEDING IN A PRIVATIZING WORLD

Intellectual property protection, globalization, and pressure on public budgets in many industrialized countries have shifted the balance of plant breeding activity from the public to the private sector. Several economic factors influence the relative shares of public versus private sector plant breeding activity, with varying results over time, over country, and over crop. The private sector, for example, dominates corn breeding throughout the industrialized world, but public and private activities in wheat breeding differ widely in Western Europe, different regions of the United States, Canada, and Australia. Public sector involvement in plant breeding may have benefits to society that the private sector's activities may not, fostering greater sharing of information and more work on traits of plant varieties (such as environmental suitability and nutritional characteristics) that may be under-researched by private breeding programs

The Contribution of Genetic Resources and Diversity to Wheat Productivity: A Case from the Punjab of Pakistan

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 yield stability-important considerations to farmers and national authorities where wheat is a staple food crop. Five indicators are used to describe the system of wheat genetic resource use and diversity in farmers' fields. The contribution of farmers' previous selections is expressed as the number of different landraces appearing in the pedigree of a cultivar . The contribution of scientific breeding efforts is expressed as the number of parental combination appearing in a cultivar's pedigree. The diversity of wheat varieties in a geographical area, as related to productivity, is captured by measures of area concentration (diversity in space) and age of varieties (diversity in time). Finally, the relative dissimilarity of cultivars grown in a geographical area is measured using a distance indicator constructed from genealogical information. Disaggregated analysis at the district level demonstrates how diversity patterns are influenced by the production environment and by possible differences in the availability of suitable varieties. The study finds no indication that modern plant breeding technologies have reduced diversity among the wheats grown in the districts of the Punjab of Pakistan during the study period, although brief. Analysis of the genealogical background of the varieties grown by farmers reveals patterns of greater use of genetic resources and dissimilarity of parentage. For some factors related to genetic resource use and diversity, there are large differences between production environments (specifically, irrigated and rainfed areas) and individual districts, which suggest that efforts to increase genetic diversity in farmers' fields will require policy instruments tailored to the individual circumstances of each production environment. Econometric results suggest that greater genealogical dissimilarity and higher rates of varietal replacement are likely to have positive payoffs relative to aggregate yield stability, while in areas where production constraints inhibit farmers' ability to exploit the yield potential of their varieties, better production management is likely to have greater yield enhancing effects than the varietal attributes related to diversity

PUBLIC SECTOR PLANT BREEDING IN A PRIVATIZING WORLD

Intellectual property protection, globalization, and pressure on public budgets in many industrialized countries have shifted the balance of plant breeding activity from the public to the private sector. Several economic factors influence the relative shares of public versus private sector plant breeding activity, with varying results over time, over country, and over crop. The private sector, for example, dominates corn breeding throughout the industrialized world, but public and private activities in wheat breeding differ widely in Western Europe, different regions of the United States, Canada, and Australia. Public sector involvement in plant breeding may have benefits to society that the private sector's activities may not, fostering greater sharing of information and more work on traits of plant varieties (such as environmental suitability and nutritional characteristics) that may be under-researched by private breeding programs.plant breeding, economics, public sector, private sector, research policy, biotechnology, intellectual property, Crop Production/Industries, Research and Development/Tech Change/Emerging Technologies,

On the Productive Value of Biodiversity

Biodiversity, Productive value, Complementarity, Scale, Convexity, Catalytic effect, D6, Q2, Q5,