Donald L. Plucknett

Crop Germplasm Conservation and Developing Countries

Loss of the genetic diversity of some of the worlds crops has accelerated in recent decades, with many crops becoming increasingly susceptible to diseases, pests, and environmental stresses. A global network of gene banks has therefore been established to provide plant breeders with the genetic resources necessary for developing more resistant crops that will enable farmers to maintain high yields. Most of these gene banks now store the germplasm of only the major crops such as cereals, potatoes, and grain legumes. Cultivated varieties of these crops are conserved as well as wild species that might otherwise become extinct. Tropical cash crops such as bananas and coconuts are also important food crops in many Third World countries, and more effort needs to be made to conserve the germplasm of these crops as well as of other important plants such as plantation crops, medicinal herbs, and fruit and timber trees.

Ex Situ Conservation of Plant Genetic Resources: Global Development and Environmental Concerns

Conservation of plant genetic resources is achieved by protection of populations in nature (in situ) or by preservation of samples in gene banks (ex situ). The latter are essential for users of germplasm who need ready access. Ex situ conservation also acts as a back-up for certain segments of diversity that might otherwise be lost in nature and in human-dominated ecosystems. The two methods are complementary, yet better understanding of this interrelation and the role of ex situ conservation in global environmental considerations is needed. Inclusion of ex situ conservation efforts within current environmental policies conserving global diversity would focus greater international attention on the safeguarding of these efforts.

Sustaining Agricultural Yields

D ramatic gains in crop yield can be ephemeral unless a follow-up research program is in place to shore up the advances. Stable yields and sustainable agriculture are as important as raising the yield ceiling of crops. The concept of shoring up yield gains applies equally to monocultures and mixed farming systems. Here we define such maintenance research, review its principles, outline its scope and dimensions, and discuss its policy implications. The effort to sustain productivity and damp oscillations in crop and livestock yields has been called maintenance research, productivitysustaining research, protective research, genetic management, or defense-of-gains research. Maintenance is an integral part of agricultural research, not a separate category. Upholding yield gains is the core concept of maintenance research, and it applies to all improved crops in both industrial nations and developing countries.

Networking in International Agricultural Research

Informal and structured collaboration is becoming increasingly common in international agricultural research. A network approach to research generally reduces costs, minimizes duplication, and boosts efficiency. Collaborative teams, sometimes involving hundreds of scientists in dozens of countries, have been formed to tackle numerous constraints to boosting food production. Networks have been established to test crop germplasm over a broad range of environments, explore ways of boosting the efficiency of fertilizer use, upgrade disease resistance in livestock, and identify socioeconomic obstacles to improved agricultural output. The benefits of networking are especially valuable to countries with limited funds and scientific manpower.

Conservation of genetic resources

Abstract An overview of current conservation systems is presented along with a general framework of principles and concepts that govern resource conservation work. The article surveys national and international genetic resource conservation programs, outlines the current state of conservation systems for plants, animals, and microorganisms, and calls for a global plan for conservation of biological diversity. Programs for plant germplasm are more organized and developed than those for animals. In situ conservation, the maintenance of a population within the community of which it forms a part, is examined, including maintenance of species of economic interest within natural ecosystems. This approach has numerous advantages and tends to conserve more than the target species. A contrasting view is given of conservation biology and agriculture as to the value of genetic conservation of wilderness areas as reservoirs for genetic variability. Ex situ conservation, the conservation of organisms outside of natural habitats, is considered especially for seeds of major crop plants. Germplasm banks fulfill an important long-term need and their functionality is dependent on the collection, characterization, preservation, and distribution of genetic resources.

International Agricultural Research for the Next Century The Consultative Group on International Agriculture increases emphasis on natural-resource management

In the last quarter century, international agricultural research has earned wide respect for its success in helping to increase world food supplies and solve critical global problems. International cooperation in agricultural research-with plant germplasm efforts leading the wayhas become an essential strategy in overcoming major problems that constrain agricultural production. No longer is it necessary for a country to go it alone in overcoming agricultural problems. International agricultural research efforts focus on crucial global or regional problems, particularly those that can only be solved by working across national borders. Agricultural research today is the worlds largest and most collaborative scientific enterprise (Plucknett 1991a). Many agricultural scientists from different countries participate; the door is always open for more scientists around the world to become involved. As an informal operation, the global system depends on goodwill and the meshing of perceived needs of numerous research organizations. Selfinterest is a strong motivator. Many developing countries participate because they are concerned that otherwise science and technology developments will pass them by. Almost every country in the world is involved in some way, including investing funds. A key player and catalyst in the

Quarantine and the Exchange of Crop Genetic ResourcesFinding the balance between protecting crops and promoting global agricultural research

he international exchange of plant germ plasm for breeding programs and gene banks has increased spectacularly during the last few decades. A need to boost and stabilize crop yields worldwide has spurred this large-scale movement of breeding materials (Plucknett et al. 1987). But concern is mounting that the risk of spreading crop pests and diseases is also increasing as a result of the accelerated pace of plant germ plasm exchange. At the same time, accusations have been made that quarantine services are not keeping pace with the volume of germ plasm shipments, the latest information on disease and pest epidemiology, nor new screening techniques, particularly those involving biotechnologies. The expanding international distribution of germ plasm poses hazards for crop production worldwide (Karpati 1981, 1983). In germ plasm collections in the United States alone, some 17 crop species have been found to harbor seed-borne viruses (Doyle 1985). Worldwide, seed-borne viruses have been found in germ plasm collections of barley (Hordeum spp.), cherries (Prunus spp.), beans (Phaseolus spp.), peas (Pisum sativum), and lentils (Lens culinaris) (Hampton 1983, Mandahar 1981). Flexibility is essential for successful

The consultative group on international agriculture research—goals, accomplishments, and current activities

Abstract The international agricultural research centers that are supported by the Consultative Group on International Agricultural Research operate as essentially independent research institutions, but with research mandates that are agreed upon by the CGIAR membership and an independent Technical Advisory Committee. The CG centers have as their goal the improvement of agriculture in the developing nations, using research as the dominant tool for change. Research activities are a blend of biological, physical, and social science efforts, often in partnership with clients in developing nations and with advanced research institutions in developing countries. Many approaches to research are used, including new relationships and modes of operation with clients, research networks, and international training linked to specific research activities. The international centers play a major role in genetic resource conservation and use, in understanding and improving farming systems, and in training of developing c...

International prospects for cooperation in crop research

Agricultural research is increasingly a global effort. No country can remain isolated in agricultural research without damaging its capacity to respond to challenges to agricultural productivity. In this paper, we explore the role of botany in the international effort to raise and stabilize farm yields. Given the importance of wild species in crop breeding and the increasing use of wild species to upgrade crops, the value of systematics is underlined. The contribution of plant physiology is also discussed, particularly with reference to mechanisms of resistance to pests and diseases and tolerance to adverse soils and climates. The crucial role of ecological studies based on field work is also underscored, particularly as it applies to wild plants and natural genepools, as well as crop protection. The necessity for continued support of botanical studies and gardens is emphasized in the light of the global effort to conserve and utilize crop genetic diversity. Finally, we examine some developments in mycology and biotechnology that have implications for agriculture and pinpoint opportunities for increased collaboration between botanists and agricultural scientists.

Tropical Forests and Their Crops

Tropical forests and their crops , Tropical forests and their crops , مرکز فناوری اطلاعات و اطلاع رسانی کشاورزی