3
In Situ Conservation of Genetic Resources

A species or a population sample of a particular part of its genetic variation can be maintained through in situ or ex situ conservation. In situ conservation is the preservation of species and populations of living organisms in a natural state in the habitat where they naturally occur. This method preserves both the population and the evolutionary processes that enable the population to adapt by managing organisms in their natural state or within their normal range. For example, large ecosystems may be left intact as protected reserve areas with minimal intrusion or alteration by humans. Ex situ conservation is the preservation and propagation of species and populations, their germ cell lines, or somatic cell lines outside the natural habitat where they occur. This method maintains the genetic diversity extant in the population in a manner that makes samples of the preserved material readily available. It includes botanical gardens, greenhouses, and the preservation of seeds or other plant materials in germplasm banks under appropriate conditions for long-term storage. This chapter discusses the role of, and barriers to, in situ conservation.

THE IMPORTANCE OF IN SITU CONSERVATION

In situ conservation is an important component of the conservation and management of genetic resources. It supplements the ex situ conservation efforts of local, national, and international collections and provides some important advantages. In situ conservation



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Managing Global Genetic Resources: Agricultural Crop Issues and Policies 3 In Situ Conservation of Genetic Resources A species or a population sample of a particular part of its genetic variation can be maintained through in situ or ex situ conservation. In situ conservation is the preservation of species and populations of living organisms in a natural state in the habitat where they naturally occur. This method preserves both the population and the evolutionary processes that enable the population to adapt by managing organisms in their natural state or within their normal range. For example, large ecosystems may be left intact as protected reserve areas with minimal intrusion or alteration by humans. Ex situ conservation is the preservation and propagation of species and populations, their germ cell lines, or somatic cell lines outside the natural habitat where they occur. This method maintains the genetic diversity extant in the population in a manner that makes samples of the preserved material readily available. It includes botanical gardens, greenhouses, and the preservation of seeds or other plant materials in germplasm banks under appropriate conditions for long-term storage. This chapter discusses the role of, and barriers to, in situ conservation. THE IMPORTANCE OF IN SITU CONSERVATION In situ conservation is an important component of the conservation and management of genetic resources. It supplements the ex situ conservation efforts of local, national, and international collections and provides some important advantages. In situ conservation

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Managing Global Genetic Resources: Agricultural Crop Issues and Policies sites preserve potentially important and useful genes, many of which may be unrecognized today. Their existence enables the selective and adaptive processes that give rise to new genetic traits to continue in response to environmental stresses. These areas can be sources of genetic traits not already captured in ex situ collections. In situ reserves can also provide living laboratories for studying the genetic diversity of the wild species that are the progenitors of modern crops. Conservation of ecosystem and species diversity has traditionally been dealt with by local or national agencies responsible for wildlife and protected areas. Conservation of genetic diversity, however, has been the concern of those responsible for agriculture (including horticulture) and silviculture. This difference may partially be responsible for the perception that efforts to conserve genetic resources in situ are inadequate (International Board for Plant Genetic Resources, 1985a). More often, however, the lack of an adequate scientific and economic basis for establishing and maintaining in situ conservation efforts is seen as the major difficulty (Hoyt, 1988; International Board for Plant Genetic Resources, 1985a; Noy-Meir et al., 1989; Plucknett et al., 1987). In situ conservation has been proposed for preserving wild species that are related to domesticated crops and perennials such as forest trees, tropical fruits, or species with short-lived seeds (Ford-Lloyd and Jackson, 1986; Hoyt, 1988; International Board for Plant Genetic Resources, 1985a; Plucknett et al., 1987). For those species, in situ conservation provides the relative stability of species diversity within a coadapted community (Frankel and Soulé 1981). Some have also suggested that maintaining landraces in traditional farming systems also constitutes a form of in situ conservation (Altieri et al., 1987; Altieri and Merrick, 1987; Oldfield and Alcorn, 1987). In situ conservation may be viewed as a dynamic process that allows the continuance of the evolutionary processes that result in genetic diversity and adaptation. In situ and ex situ conservation methods are complementary options essential to the maintenance of crop and biological diversity (Office of Technology Assessment, 1987a). It has been argued that although ex situ conservation methods allow more immediate access to genetic resources, in situ conservation methods are essential for the conservation of a broader range of species (Brown et al., 1989; Office of Technology Assessment, 1987a; Oldfield, 1984; Plucknett et al., 1987). In addition, an in situ conservation area can encompass a broad range of species and genetic diversity, much of which may not even be described. In situ conservation is particularly important for trees (Ford-Lloyd and Jackson, 1986; National Research Council, 1991b).

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Managing Global Genetic Resources: Agricultural Crop Issues and Policies The lengthy generation times make conservation of tree populations in their natural environment essential for any sort of experimental use. WILD SPECIES AS GENETIC RESOURCES Wild species are often used to improve established crops and occasionally used to develop new ones. A survey of 18 crops grown in the United States from 1976 to 1980, revealed that from 1 percent (sweet clover) to 90 percent (sunflower and tomato) of the available cultivars had been improved in part using wild germplasm. The combined average annual farmgate value of these cultivars was $4.8 billion (the annual value of the improvements to eight of the crops was estimated by one report to have been $170 million) (C. Prescott-Allen and R. Prescott-Allen, 1986). Use of wild relatives in crop breeding has obvious economic significance and is growing (C. Prescott-Allen and R. Prescott-Allen, 1986; R. Prescott-Allen and C. Prescott-Allen, 1983). Colorado potato beetles take only a bite or two of this insect-resistant potato plant before they are repelled. The plant has been genetically engineered to contain a gene from wild potatoes that produces a substance distasteful to these insects. Credit: U.S. Department of Agriculture, Agricultural Research Service.

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Managing Global Genetic Resources: Agricultural Crop Issues and Policies The likelihood that a wild genetic resource will be used in crop breeding is a function of the economic importance of the crop, which determines the existence and size of any improvement program; the rarity of the character being sought and the possibility of locating it in the gene pool of the domesticated crop; and the ease with which the character can be transferred from the wild relative to the domesticated crop. Breeders in search of a particular character may explore quite thoroughly the variability of the crop itself. However, they seldom explore much of the variability contained within its wild relatives. Breeders generally test small numbers of accessions from limited portions of the wild species' range (Rick et al., 1977), but the size of most collections of wild relatives available in ex situ storage are small and often do not reflect the full variability available in situ. Wild gene pools are an important biological resource for developing new crops, particularly for the timber industry, the livestock industry (forage and fodder crops), and rural development (fuelwood). Like the breeders of established crops, domesticators of new crops differ in the extent to which they explore the genetic variability of the species concerned. In general, the economically most successful new domesticated crops are those that have tapped a diversity of germplasm sources (C. Prescott-Allen and R. Prescott Allen, 1986). Genetic Conservation Areas Wild genetic resources may be conserved in situ in a protected area. This is an area of land or water allocated to some form of conservation management. It may be established expressly to maintain the genetic resource, or it may have other objectives as well. Both types of genetic conservation areas are included in the term genetic reserves Jain, 1975a). The principal objective of a genetic reserve is to maintain the individual and population-level variation of one or more species in their natural range or habitats. Genetic reserves have the following characteristics: An explicit objective to maintain population variation. An established protocol for providing information on and access to the protected resources by ex situ collections, breeders, researchers, and other germplasm users, including a procedure for the sustainable collection of reproductive material by authorized agencies and individuals. A procedure for monitoring the status of the populations conserved as part of a national genetic resources information system. The primary role of the genetic reserves is to secure the long-term

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Managing Global Genetic Resources: Agricultural Crop Issues and Policies availability of their wild genetic resources and to preserve the adaptive processes therein. Consideration of the extent to which intraspecific variation is encompassed in an area is required to preserve the genetic structure of the target species. Multiple sites may be required to capture a reasonable amount of the allelic variation of a species (Food and Agriculture Organization, 1989a). For example, the committee has examined the challenges of preserving the genetic structure of forest trees (National Research Council, 1991b), the in situ conservation of which is particularly important because of their lengthy generation times (Ford-Lloyd and Jackson, 1986). As discussed in greater detail in Chapter 4, the targets of germplasm sampling strategies are common alleles (population frequency, equal to or greater than 5 percent) that are widespread (found in many populations) or local (found in one or a few populations) (Brown and Moran, 1981; Marshall and Brown, 1975). These common alleles define representative and unique gene pools that could be candidates for in situ conservation. However, the characterization of gene pools is not necessarily a simple task. The variation among alleles can be inferred individually through studies of intraspecific variation in biochemical characters (for example, enzymes, other proteins, or terpenes), morphology, phenology, growth rate, environmental adaptations, and many other characters. Direct measures of DNA variation are also possible using restriction fragment length polymorphisms or randomly amplified polymorphic DNA markers (see Chapter 7). Genetic variation in characters strongly influenced by environment (phenology, growth rate, morphology of vegetative parts) must be measured through tests that compare responses with different environments. There are, however, few studies of the degree to which biochemical variability reflects morphologic or other phenotypic variation (National Research Council, 1991b). THE STATUS OF IN SITU CONSERVATION OF WILD TYPES The need for in situ conservation of wild genetic resources has been widely acknowledged (Food and Agriculture Organization, 1989a; Hoyt, 1988; International Board for Plant Genetic Resources, 1985a; International Union for the Conservation of Nature and Natural Resources et al., 1980; Jain, 1975a,b; Noy-Meir et al., 1989; Office of Technology Assessment, 1987a; Oldfield, 1984). However, real efforts at in situ conservation have been slow to emerge (International Board for Plant Genetic Resources, 1985a; Noy-Meir et al., 1989). At least

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Managing Global Genetic Resources: Agricultural Crop Issues and Policies In a test field at the Forage and Range Research Laboratory of the U.S. Department of Agriculture, a research geneticist examines hybrids made by crossing native American wild ryegrasses with a wild species from the former Soviet Union. These new, taller ryegrasses stay green later, reducing fire hazards, and may enable animals to graze 2 months longer than usual each year. Their leaves cure well and protrude above the snow so cattle and sheep can graze them well into the winter. Credit: U.S. Department of Agriculture, Agricultural Research Service. three comprehensive national initiatives have been reported. In Brazil the Centro Nacional de Recursos Geneticos (CENARGEN, National Genetic Resources Center) has established 10 genetic reserves to maintain timber, fruit, nut, forage, and palm species and wild retives of crops such as cassava and peanut (Giacometti and Goedert, 1989). Germany is using its system of nature reserves as the basis of in situ conservation of the wild progenitors of apples and pears and other wild genetic resources (Schlosser, 1985). The Commonwealth of Independent States is reported to have established 127 reserves for the protection of wild relatives of crops (Korovina, 1980). A few reserves have been designated for the protection of particular

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Managing Global Genetic Resources: Agricultural Crop Issues and Policies wild relatives or for timber genetic resources. They include the Sierra de Manantlán Biosphere Reserve in Mexico for teosinte (Zea diploperennis) (Hoyt, 1988; Russell, 1989) and two reserves each for Zambesi teak (Baikiaea plurijuga) in Zambia and Pinus merkusii in Thailand (Food and Agriculture Organization, 1989a). Few reserves have been established or are managed as genetic resources conservation areas. A European survey of wild crop relatives of apples, plums, cherries, peaches, almonds, and Allium species found that although reserves existed within the range of these wild species, lists of the plant species they contained were available for few of those areas. No information on genetic diversity was available (Hoyt, 1988). The goals of genetic conservation can be combined with those of natural or biosphere reserves. A notable example of in situ conservation is teosinte, a wild relative of maize, which is found in Mexico and Guatemala (Centro Internacional de Mejoramiento de Maíz y Trigo, 1986; Plucknett et al., 1987; Wilkes, 1977). In an effort to preserve the genetic resources of teosinte, the Centro Internacional de Mejoramiento de Maíz y Trigo (CIMMYT, International Maize and Wheat Improvement Center) in Mexico and others are using a combination of methods that include in situ monitoring of teosinte populations and preservation in reserves (Centro Internacional de Mejoramiento de Maíz y Trigo, 1986). Teosinte is generally found in the untilled soil bordering maize fields and, to a lesser degree, throughout some maize fields. There are eight geographically isolated population clusters of annual teosinte. Six of these are found in Mexico and two are found in Guatemala. There are also two perennial populations in Mexico. Teosinte populations range in size from 1 to 1,000 square kilometers. It is estimated that the current distribution of teosinte is half of what it was in 1900 (Centro Internacional de Mejoramiento de Maíz y Trigo, 1986). Three of the annual populations are considered rare, occurring at single locations. Most of the populations are considered vulnerable and are declining at a rate such that they could become endangered. There are three principal threats to teosinte populations (Centro Internacional de Mejoramiento de Maíz y Trigo, 1986). As land use is intensified, teosinte is squeezed out of the margins bordering maize fields. The replacement of maize with cash crops, such as short-stature sorghum, leaves teosinte as a visible weed, making it easier to remove. Finally, because of outcrossing to maize, small and isolated stands of teosinte can lose their ability to disperse. CIMMYT staff make yearly visits to identified annual teosinte

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Managing Global Genetic Resources: Agricultural Crop Issues and Policies population sites to assess the status of each population. If a population is found to be endangered, CIMMYT and national program staff can cooperate preserve it. This allows monitoring of teosinte without incurring the costs of establishing and maintaining an in situ preserve. There are other examples of genetic conservation goals being combined with those of natural or biosphere reserves. In 1988, Mexico established the 139,000-ha Sierra de Manantlán Biosphere Reserve (Hoyt, 1988). A small portion of this reserve (about 10 ha) contains the only known stands of the primitive wild relative of maize. Zea diploperennis. Earlier, in 1959, the 23,868-ha Sary-Chelck Reserve was established in the Commonwealth of Independent States as part of the Chatkal Mountains Biosphere Reserve, near western China. The area contains wild species related to walnuts, apples, pears, Prunus species, and other temperate fruit and nut crops (Hoyt, 1988). Obstacles to In Situ Conservation of Wild Genetic Resources Two main obstacles to in situ conservation of wild genetic resources are sectoralism and lack of knowledge (R. Prescott-Allen, resource policy analyst, personal communication, June 1990). The conservation focus of protected areas is typically on the level of ecosystems and species, not on the maintenance of crop genetic resources. To the extent that agencies responsible for protected areas are aware of the need for conserving genetic resources, they tend to regard it as an additional responsibility for which additional resources are generally not forthcoming. Ministries of agriculture or their equivalents have a direct interest in conserving wild relatives of crops, but they may be ambivalent about the importance of in situ conservation. In part, this may be because they often lack authority over the appropriate lands. Thus, difficulties in establishing a protected area may quickly outweigh the benefits of doing so, especially if the goal is protection for only one or two wild relatives of a single crop. Lack of knowledge of the degree and distribution of interpopulation genetic variation in the wild relatives of crops is another obstacle (International Board for Plant Genetic Resources, 1985a; Noy-Meir et al., 1989). This information is needed for answering questions such as where in situ conservation areas should be established, how large should they be, and what ways should they be managed. Ecogeographical surveys (International Board for Plant Genetic Resources,1985a) that assess the genetic variation of a species across its entire geographical and ecological range are needed (Hoyt, 1988). It can take years to obtain a complete ecogeographical survey. Although

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Managing Global Genetic Resources: Agricultural Crop Issues and Policies TABLE 3-1 Crops for Which In Situ Conservation and Ecogeographic Surveys Are High Priorities Crop Wild-Type Relative Location Groundnut Perennial Arachis spp. Latin America Oil palm Elaeis spp. Africa, Latin America Banana Wild-type diploid Musa spp. Asia Rubber Hevea spp. Amazonia Coffee Coffee, Arabica spp. Africa Cocoa Theobroma spp. Latin America Onion family Selected wild-type Allium spp. Worldwide Citrus Wild-type Citrus spp. Asia Mango Wild-type Mangifera spp. Southeast Asia Cherries Wild-type Prunus spp. Europe, Asia Apples Wild-type Malus spp. Europe, Asia Pears Wild-type Pyrus spp. Europe, Asia Forages Hundreds of species Worldwide   SOURCES: International Board for Plant Genetic Resources. 1985. Ecogeographical Surveying and In Situ Conservation of Crop Relatives. Rome: International Board for Plant Genetic Resources; Hoyt, E. 1988. Conserving the Wild Relatives of Crops. Rome: International Board for Plant Genetic Resources. such information is of potential value to all crops, related wild species with high priority have been identified (Table 3-1). Population dynamics studies of a wild emmer wheat (Triticum dicoccoides) in Israel promise to provide important answers to basic questions about in situ conservation (Noy-Meir et al., 1989). The study is aimed at addressing questions about the genetic structure of an in situ population and how it changes over many years. The effort combines ecogeographic survey information with topographic studies and population dynamics. Morphologic, phenologic, yield, phytopathologic, and biochemical (allozymes, seed storage proteins) data are all being gathered (Noy-Meir et al., 1989). Although they are expected to yield a wealth of information useful to the management of wild species in situ, the data are also likely to provide results relevant to the sampling of populations for ex situ conservation (see Chapter 4). The Potential of Using Existing Protected Areas as Germplasm Banks The International Union for the Conservation of Nature and Natural Resources (1978) classifies protected areas into eight categories according to broad management objectives. All could provide for conserving

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Managing Global Genetic Resources: Agricultural Crop Issues and Policies wild genetic resources, but five are particularly suitable: nature reserves, national parks, natural monuments, managed nature reserves, and managed resource areas. The first three are suitable for maintaining climax populations because they do not permit artificial maintenance of seral or subclimax stages. Managed nature reserves and managed resource areas usually permit such intervention, and so are suitable for maintenance of pioneer and subclimax as well as climax populations. Protected areas in the first four categories above cover 4.5 × 106 km2, an area almost half the size of the United States (R. Prescott-Allen, resource policy analyst, personal communication, June 1990). Many of them contain major wild genetic resources species. For example, Kora National Reserve in Kenya contains seven such species; they are Vernonia galamensis, Cenchrus ciliaris, Panicum maximum, Sorghum arundinaceum, Acacia senegal, Gossypium somalense, and Populusilicifolia (Kabuye et al., 1986). St. Lawrence Islands National Park in Canada contains 27 such species (R. Prescott-Allen and C. Prescott-Allen 1984). While acknowledging that many wild genetic resources species may be found in existing protected areas, the International Board for Plant Genetic Resources (1985a) has noted several deficiencies that could impair their utility for conserving genetic resources. (1) Most protected areas lack adequate inventories of species or genotypes. (2) Many populations of wild relatives of crops in existing protected areas are too small for maintenance of allelic diversity or even for survival of the species. (3) Minimum conservation requirements for maintaining intraspecific diversity are not considered. (4) The limited monitoring that may be carried out is often insufficient to guarantee conservation. Most of these deficiencies can be corrected when conservation of wild genetic resources becomes an objective of the protected area. However, the problem of population size casts doubt on the adequacy of existing protected areas for conserving genetic resources. The complexity of the concept of a viable population (Soule,é, 1987) and the dearth of information on viable populations means that the extent to which protected areas maintain adequate populations of genetic resources species is not known. Although most protected areas were not designed to maintain allelic diversity of the wild relatives of crops, and although they are not managed to conserve intraspecific diversity, it does not follow that they do not do so, albeit fortuitously. Those responsible for existing protected areas could add in situ genetic conservation to their objectives for the use of those areas. This would require a listing of genetic resources species for in situ

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Managing Global Genetic Resources: Agricultural Crop Issues and Policies conservation, a check of the inventories of existing protected areas for the presence of populations that warrant conservation, and modification of the management plan to include monitoring of the status of the populations and to facilitate access to information on the resources. These steps can be taken now, without waiting for information on the degree and distribution of genetic variation within priority species. As such information is obtained through genetic and ecogeographical surveys, it can be used to amplify and refine conservation efforts. In this way, proposed conservation can complement existing protected areas and close serious gaps. THE STATUS OF IN SITU CONSERVATION OF DOMESTICATED TYPES It has been argued that maintaining traditional landraces of domesticated crops in the peasant agroecosystems in which they developed is a form of in situ conservation (Altieri and Merrick, 1987; Altieri et al., 1987; Oldfield and Alcorn, 1987; Wilkes, 1989b). In situ conservation in agroecosystems requires maintenance of the particular socioeconomic conditions (or their substitution with equally favorable incentives) as well as appropriate ecologic conditions (Altieri et al., 1987; Oldfield and Alcorn, 1987). The introduction of modern crop varieties has led to the decline and loss of many traditional landraces and the agricultural systems that produced them (Altieri and Merrick, 1987; Frankel and Hawkes, 1975a). There are few studies of the factors that promote loyal use of traditional landraces and local varieties (one example is Brush [1977]). There may be circumstances in which the special qualities of a landrace outweigh the modern cultivar's advantages of high yield and high return per unit of labor. An understanding of the cultural and economic factors that may promote the loss of some landraces and the persistence of others and that may lead some individuals and communities communities to adhere to their local cultivars while others discard them is essential for long-term in situ conservation of these resources. In situ conservation of landraces has been proposed to preserve not only crop resources but also to perpetuate the adaptive evolutionary processes that produced them (Brush, 1977; Nabhan, 1985, 1989; National Research Council, 1978; Oldfield, 1984; Oldfield and Alcorn, 1987; Wilkes and Wilkes, 1972). Traditional or peasant agricultural systems are frequently polycultures that include minor crops and other potentially useful plants (Alcorn, 1981; Oldfield, 1984; Oldfield and Alcorn, 1987; S. Brush, University of California, personal communication,

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Managing Global Genetic Resources: Agricultural Crop Issues and Policies May 1989). In addition, the in situ maintenance of landraces and their agroecosystems preserves the complex relationship and competition between wild crop relatives and the weeds that may be associated with them (Oldfield and Alcorn, 1987). There are, however, several constraints to conserving crop landraces in traditional agroecosystems (Ford-Lloyd and Jackson, 1986; International Board for Plant Genetic Resources, 1985a; Oldfield and Alcorn, 1987; Plucknett et al., 1987). It is unlikely that any mechanism could be developed for more than a small portion of the large number of landraces of even the major crops. Such programs will require a substantial degree of monitoring to ensure that farmers do not abandon cultivation of landraces or traditional varieties in favor of new varieties. Ultimately, incentives may be necessary to encourage farmers to retain and continue traditional practices (Altieri et al., 1987; Altieri and Merrick, 1987; Oldfield and Alcorn, 1987; Plucknett and Smith, 1987). This will necessitate a permanent commitment to a long-term program similar to that which is necessary to maintain an ex situ collection. The activity of Native Seeds/SEARCH is a model of how in situ conservation can be accomplished if the local community is given appropriate incentive. This group combines in situ and ex situ methods in the conservation of traditional cultivars of the southwestern United States and northwest Mexico. The organization provides encouragement and assistance to Native American and other farmers in these areas to grow their traditional cultivars; it also conserves their traditional varieties and landraces in medium-term, ex situ collections (Nabhan, 1989). In situ conservation of domesticated genetic resources is usually more difficult than that of wild genetic resources, and little is known about the factors that would favor it. It has been argued that in situ conservation has a potentially valuable role to play in an integrated system for maintaining genetic resources. It may be particularly valuable for conserving landraces in regions with crop diversity, thus allowing continued adaptation and evolution. RECOMMENDATIONS Genetic resources must be an integral part of the objectives of existing conservation efforts. In situ conservation provides the capacity to protect a wide range of genetic and species diversity and the adaptive processes that shape them. The scientific understanding necessary to achieve the most effective in situ conservation is, however, only just beginning to emerge. Cultural and economic factors

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Managing Global Genetic Resources: Agricultural Crop Issues and Policies likely to impede or promote long-term, in situ conservation of domesticated genetic resources often still need to be identified. Research is needed to elucidate the components for establishing viable and genetically diverse populations of wild species. At present, no integrated predictive capability exists for determining the potential longevity of populations in relation to their size and structure (Shaffer, 1987). Protected populations should be large enough to be self-regenerating and to minimize loss of rare alleles. In the absence of information on the species concerned, a minimum population size of 500 individuals has been suggested (Frankel and Soulé, 1981). However, it has since been shown that such numbers fall far short of encompassing the range of demographic, life history, genetic, and environmental factors that confront in situ conservation (Soulé, 1987). Unique, endangered wild populations that have present or potential value as crop genetic resources should be conserved in situ. In general, in situ conservation will focus on wild species. When establishing reserves for crop genetic resources, consideration should be given to wild relatives of crops that are the subject of improvement programs. Attention should also be given to wild species for which there is information on both crossing ability with the crop and on potentially useful genetic traits. Finally, wild species that are in the early phases of domestication are also important. They include many timber and forage species for which the interpopulational genetic variation of the wild species is being explored and used (see National Research Council, 1991b). Existing protected areas should form the nucleus of a system for in situ conservation of genetic resources. The protected areas would benefit from serving as wild genetic resources areas since it would increase their value to society. The alternative— a separate network of genetic resources conservation areas, developed more or less independently from conventional protected areas— is unlikely, since competition for land is so intense that it is increasingly difficult to establish new protected areas, particularly if their purpose is narrow, such as the protection of a single species. A redirection of existing activities, although simpler than establishing new reserves, will still require investment. In many developing countries, none of this will happen without permanent financial assistance.

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