In situ conservation of crop genetic resources is a complementary strategy to ex situ conservation, requiring the active participation of farmers in maintaining local and traditional crop varieties. The purpose of on-farm conservation is not to preserve genetic diversity as such but to sustain crop evolution in selected habitats and farming systems, involving human and natural selection of diversity in cropping systems and the exchange of crop germplasm among populations. Research in several centers of crop origins and diversity demonstrates that a form of in situ conservation is widely practiced in cradle areas of crop domestication and diversity. Environmental heterogeneity, risk, and missing markets contribute to this practice. Social science is necessary in planning in situ conservation, to identify regions and types of farmers who should be involved and policies that will be effective. Illustrations from research in Peru, Mexico and Turkey are used.
Keywords: genetic resources, conservation, crops.
All crops evolved from wild species as a result of human activity at specific locations. Therefore, crop domestication consisted of the interaction between plants, their environment, and human beings. These interactions occurred from the early selection by humans of wild ancestors of current crops, and have remained throughout the cultivation of landraces by farmers, or the development of new cultivars by modern plant breeders. At the beginning of agriculture, these interactions took place in the centre of origin of each specific crop, and after that extended to the centres of diversity. Nowadays, it may be seen in farmers’ fields and it breeding stations and testing sites for cultivar development. Total genetic diversity in a crop species depends on the frequency of alleles controlling morphological and physiological characters selected during human domestication. For example, genes controlling the growth cycle (e.g. time of sowing or date of harvest) influence the evolution and domestication of most popular annual seed crops, and determine their rate and scale of adaptation. Thus, population structure of crop species arose from their original diversity patterns that could have been affected by the length of their life cycle. Consequently, the specific level of genetic variability observed in a defined crop population resulted from joint effects of mutation, migration, recombination, selection (both natural and artificial), and random genetic drift (i.e., changes due to change in small populations). Gene mutation, and gene flow via migration and recombination enhanced variability, whereas selection and genetic drift often tended to reduce this variability. Changes in gene frequency of favourable alleles, which increased crop fitness to the human-made environment for agriculture, were the driving force during the evolution of crop species. Owing to some morpho-physiological changes, the survival of some crop species depends today on human agriculture. The domestication and further evolution of some crops were also affected by isolating mechanisms, such as the natural pollinator(s), geographical barriers, self-incompatibility, sterility, and vegetative propagation. A dynamic system for preservation of plant genetic resources, such as in situ conservation (ISC), should be considered for crop species and their life relatives, because it allows the competition of crop population with other indigenous plants in their permanent or original eco-niches. Likewise, ISC permits interaction between the crop, its wild relatives, and in some sites their co-evolution with the pathogens affecting each species. Although many crops may be chosen for ISC, available resources have become the limiting factor for such a task. The most promising candidates for ISC are vegetatively propagated perennial crops, and those with recalcitrant seeds not amenable for ex situ gene bank conservation. Analysis of the pattern of allelic diversity in each crop and its wild relatives, may allow the development of a comprehensive ISC strategy for the preservation of plant genetic resources.
There is a great richness of species diversity in the wild growing plant genetic resources of Germany. An estimation resulted in 1 150 species belonging to different groups of use. This figure has been taken for a rough calculation of the global plant genetic resources – 115 000 species. This number, which is based in the results of only one country, should be further elaborated. But its dimension shows that most of the wild plant genetic resources, which are globally threatened by genetic erosion, should be maintained, though breeding and breeding research are increasingly interesting in this material and accordingly gene banks make efforts for its conservation. A complementary system for maintaining plan genetic resources is necessary, considering also the wild relatives of crop plants and other useful materials.
In this paper is briefly presented domestication and breeding of sea buckthorn in China, Russia and Europe. Sea buckthorn has been known and used by humans for centuries in both Asia and Europe. Russia and China are leading countries in the area of domestication, breeding, cultivation and introduction of products on the market. Sea buckthorn is a multipurpose plant with nitrogen fixing capacity and the chemical composition of the berries is unique amongst the wild berries from the Northern Hemisphere. However, after many years from the start of domestication programmes with sea buckthorn no large commercial plantations have been established in Europe. The main problem in developing of growing systems is the mechanical harvesting. Furthermore, evaluation and characterisation of genetic diversity presented in this paper is very important for the future preservation and sustainable usage of genetic resources.
Ecuador, and other Andean countries, is one of the world’s important regions for agro-biodiversity conservation and management. Ancient civilizations settle in the region several millennia ago and domesticated native plant species, such as potato, that today are some of the most important crops in the world. Other crops are of local importance or are endemic to this region. The preservation and management of genetic resources in Ecuador is recent event. In early 1980’s, the Ecuadorian Agricultural Research Institute (INIAP) started to collect and preserve native Andean crops. As a result of this, a national gene bank was established as means of ex situ conservation in order to preserve this important germplasm. In recent years, researchers have identified a need for in situ conservation and the establishment of a link between the gene bank and local farming communities. In addition, relationships between in situ and ex situ conservation have to be established in order to use the genetic resources wealth conserved in gene banks. In this way the importance of ex situ conservation will increase due to the return of seeds to the communities. An in situ conservation program, initiated as part of an integrated management system of agro-biodiversity conservation in the Rio Pataza valley communities of Chimborazo-Ecuador, currently focuses on Andean Root and Tuber crops (RTA). The integrated system includes soil and water conservation and management, forest and other minor and local food crops.
Keywords: conservation, in situ, ex situ, Ecuador.
The Brassica oleracea cytodeme, with the chromosome number 2n = 18, consists on one hand of horticultural crop plant, as a result of domestication of B. oleracea in particular, and on the other hand of numerous wild species. The wild, perennial species inhabit maritime habitats, mostly coastal limestone cliffs and rocky islets, and occur as vicarious species in the Mediterranean region and along Atlantic coasts. Diversity within and between species has been studied with molecular methods in particular. Analysis of gene diversity values indicate a considerable within population variation regardless of population size. However, the level of homozygosity tends to be higher in smaller populations. Even adjacent populations, which are geographically separated by a few kilometres only, show quite different isozyme patterns indicating that gene flow between populations is highly restricted. RFLP analysis showed that the ten wild species tended to cluster into four groups according to their geographic regions. Crossing experiments lead to the conclusion that all cultivated forms including the Chinese B. alboglabra and the wild species belong to the same cytodeme. Sicily is considered to be an important centre of diversity of wild Brassica species, but actual or potential threats have been recognised in at least half of the Sicilian populations. Due to the present situation a plant for dynamic in situ conservation of the Sicilian species is proposed.
Keywords: Brassica oleracea, in situ conservation.
A methodology for in situ conservation of plant genetic diversity in a genetic reserves has recentky been established. This paper attempts to provide both a theoretical and practical overview of the techniques involved in the location, planning, establishment, management and utilisation of the genetic resources conserved within the genetic reserve. The practical interpretation of the methodology is illustrated using the endemic coffee species of the Mascarene Islands; namely C. mauritiana Lam., C. macrocarpa A. Rich. and C. myrtifolia (A. Rich. ex DC.) Leroy. It is hoped that the paper will demonstrate the effectiveness of the general methodology proposed, provide an exemplar that could be followed for other taxonomic groups, as well as, illustrating how the methodology has been efficiently applied to conserve a particular group of important plant genetic resources.
In situ conservation on-farm has been defined in numerous ways depending on the different objectives of the interested parties involved. Key to each of these objectives is identifying who is the targeted beneficiary of the socio-economic, ecological and genetic benefits from in situ conservation on-farm. In common to all interested parties is a concern about (1) why and who diversity is being maintaining and (2) how to sustain and possible enhance its maintenance over time. Crop genetic resources are affected by both natural and human selection pressures from the agroecosystem that surrounds them. Environmental, biological, cultural and socio-economic factors influence a farmer’s decision of whether to select or maintain a particular crop cultivar at any given time. Farmers, in turn, make decisions in the process of planting, managing, harvesting and processing their crops that affect the genetic diversity of the crop populations. The challenge of understanding the mechanisms of in situ conservation on-farm resulted in the International Plant Genetic Resources Institute (IPGRI), together with national partners in nine countries and technical experts, formulating a global project to “strengthen the scientific basis of in situ conservation of agricultural biodiversity”. The participants are focused in six areas: (1) socio-economic, cultural and biological influences on farmer decision-making, (2) population structure of local cultivars, including population size, isolation, and geneflow between and within cultivars and crop wild relatives, (3) farmer selection of agromorphological characters, (4) environmental selection by agroecosystems, including natural factors (e.g. soil, precipitation, temperature, disease, etc.) and managed factors (fertilized application, irrigation, weeding, harvesting practices, etc.), (5) seed/germplasm supply and storage systems, and (6) enhancing the benefits of local crop resources. In situ conservation on-farm is a platform where the objectives of conservationists, environmentalists, and economic and social development workers all have a place. It is a scheme that offers the rare opportunity for both farmers and society to achieve socio-economic, ecological and genetic benefits within the same strategy.
A database management system (DBMS) for in situ conservation must be general enough to handle all forms of in situ preservation (in nature, in culture, in cultivation), and at the same time specific enough to be able to handle the special requirements for each type. The space-time dimension of in situ conservation schemes can be includes in Geographic Information Systems (GIS) software. But a comprehensive database management system should, in addition, be able to handle both agricultural and ecological aspects as well as aspects on changes in genetic composition of the populations. For full control and maximum payoff a hybrid solution integrating GIS with germplasm documentation DBMS in a relational database environment is needed.
Keywords: database management system, in situ conservation, germplast.
Forage grasses and legumes have traditionally been conserved ex situ in speed banks. One criticism against the ex situ conservation methods is that it stops evolution that occurs in a changing environment. In situ and on-farm conservation is an interesting conservation method in forages. During our recent history a large number of landraces have been adapted to different local growing conditions. Usually the landraces are inferior to commercial cultivars. Grindstad timothy is an exemption, as it is the best timothy cultivar in southern Norway. Grindstad is a good example how a landrace evolves over time to changing agricultural practices and demonstrates in a good way how powerful on-farm conservation can be in changing a landrace in a useful direction. In situ conservation should not be seen as an alternative to ex situ conservation, but rather as a useful complementary method.
Keywords: in situ conservation, ex situ conservation, on-farm conservation.
Conventional concepts of conservation of biodiversity, and genetic diversity as one of its elements, have been built on a misconception that maximum adaptedness of species or populations has already been obtained in nature. As a consequence of that misconception, the present genetic constitution was identified as the prime objective of conservation. That in turn resulted in a static character of conservation where no active silvicultural measures were allowed. However, conventional conservation of forest genetic resources that is based on non-interference approach is not able to cope with systematic pressures and stochastic perturbations that arise from extensive expansion of man’s activity into forest lands, and rapid man made global and local environmental changes. The extensive static forest gene conservation system that was developed during last 30 years period in Lithuania has clearly demonstrated its inefficiency and insecurity. The prime objective of gene conservation should be defined to ensure a continuous survival, adaptation, and evolution of the species over unlimited number of generations in continuously changing environment. To reach that objective it is needed to promote the maintenance of a broad genetic variation and to create good conditions for fast adaptation of each species. The gene conservation must be dynamic and based on evolutionary and population genetics. To reach the objectives stated, the conventional static forest gene conservation system should be transformed into dynamic ones that are based on the Multiple Population Breeding System (MPBS) concept which combines secure and sustainable conservation of forest genetic resources, preparation for possible ecoclimatic changes, and efficient tree breeding. The MPBS means that the gene resource conservation/breeding population should consist of 10-20 small subpopulations, each with an effective population size of 50 genetic entries. A gene conservation network of both natural in situ subpopulations as well as synthetic ones ex situ ought to be established over a broad array of ecoclimatic conditions. The essence of dynamic gene conservation by using the MPBS concept is to promote adaptation by exposing the gene resource population to natural selection and in turn to evolution in a variety of directions. The selection and sampling should sufficiently cover geographical patterns of both species genetic variation and ecoclimatic conditions. In situ gene conservation subpopulations could be established on the areas of most suitable conventional gene reserves. Ex situ subpopulations should be established as regular progeny test plantations where new generations will be created using open pollination or by crossing the 50 best individuals selected within the families. Gene conservation populations should be intensively managed to improve the adaptation of each subpopulation, to increase genetic differences between them, guarantee their sustainability during all periods of ontogenesis, continuous regeneration of population of target species, and protection against all types of damages. In order to save costs the gene conservation ought to be carried out jointly with tree breeding and genetic studies.
In Lithuania one of the main methods of forest genetic resources conservation is in situ. This method leads to conservation of the whole genetic diversity and natural development of populations. Selection of forest tree genetic resources is based on the principles of value and necessity. In Lithuania four strict forest genetic reserves, 203 genetic and 72 seed reserves were singled out. The most stable sustenance of forest genetic resources in situ is achieved when a stand grows on sites optimal for the species providing conditions for its natural development and regeneration.
Traditional fruit crops for Estonia are the following: apple, pear, plum, bullace, sour cherry, sweet cherry, strawberry, raspberry, red (and white) and black currant, and gooseberry. The most perspective new crops are sea buckthorn and edible honeysuckle. From 75 tree fruit cultivars, 33 small fruit cultivars, six cranberry cultivars, and eight apple clonal rootstocks of Estonian origin, seven apple, four strawberry, and black currant cultivars are not saved up to the present time. Genetic erosion of germplasm (selections) of amateur breeders is much greater.
A historical review of the utilization of economically important wild plants in Lithuania is presented. The purchase dynamics from 1946 until 1990 for wild fruits and berries, medicinal plants, fresh and dried mushrooms is reviewed. Resources of wild and economically important forest plants were evaluated by means of standwise inventories in forest. Some climatic, environmental and social changes decrease the natural habitats of these wild plants and endanger their survival. A legislative basis for preservation of wild flora in Lithuania has been provided through governmental acts and regulations.
The recreational needs of Lithuania people, forest loads and activity of resting people were determined by sociological studies. The regularity of regional digression of forest are analyzed on the basis of 200 permanent and temporary research plots. Theoretical fundamentals of assessment of these processes, criteria of assessment and methodical requirements are reviewed. A general conclusion on the optimization of recreational forest’s use is presented. On the basis of these studies it was possible to prepare a system of organizational – economic means and standards of forest use for recreation.
Keywords: recreation, digression of ecosystems, ecological capacity, optimization of use.
The importance of on-farm conservation for the Finnish landraces and old varieties of cereals and fodder plants is briefly discussed and the on-going project of Finnish landraces represented. The project was started in 1997 by the Seed Testing Department of the Plant Production Inspection Centre in order to link on-farm conservation efforts and seed distribution possibilities. The project aims to make a proposal for a system of characterization, registration, on-farm management and seed marketing of landraces and old Finnish commercial varieties (cereals, forage species). The key aspects of the proposal, which is constructed by the end of 1998, are presented in this shot note.
Keywords: landrace, old commercial variety, characterization, registration, on-farm conservation.
This paper is a first attempt to systematise the knowledge about the potential of the natural Latvian grasses for purposes of plant genetic resources.
A brief presentation of the results of field studies on small fruit, medicinal and aromatic plant genetic resources conservation in situ in south eastern Lithuania is given. The problems of in situ conservation are being discussed.
Keywords: small fruit, medicinal plants, plant genetic resources, conservation in situ, plant populations, ecosystems, protected areas.
Conservation of genetic diversity is the key issue in sustainable conservation of biodiversity. The prime objective for gene conservation should be defined a creation of favourable conditions for continuous adaptation and evolution of the species. The Multiple Population Breeding system (MPBS) would be applicable with high efficiency for conservation of English oak in Lithuania.