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Silo National des Graines Forestières BP 5091, 101 Antananarivo Madagascar |
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INTRODUCTION Madagascar is a unique country for its biological diversity, including exceptionally high levels of endemism. Its natural ecosystems play an important role in the protection of arable lands and regulation of water supply and also strenghten the country's potential for ecotourism. The "Silo National des Graines Forestières" (SNGF) founded in 1988 is responsible for the management and development of forest genetic resources for reforestation and afforestation in Madagascar. Among 1200 palm species found world-wide in tropical and subtropical regions, 120 are found in Madagascar. These range from the tiny Nephloga to the giant Borassus and Neodypsism, to Ravenea for which there is a strong international demand for seed. Delonix regia (giant royal poinciana), a beautiful ornamental tree species widely planted throughout the tropics, is an endemic Malagasy species, naturally occurring in forests growing on limestone escarpments. A number of these tree species are symbols of Malagasy tourism, including "the traveller's tree" (Ravenala madagascariensis) and baobabs (Adansonia spp.) which are represented by eight species. Forests of alluvial land include important reforestation species such as Canarium madagascariensis, Khaya madagascariensis and Terminalia mantaly. Many valuable timber species grow in the moist forests in the east and the deciduous forests in the west, including Intsia bijuga (Madagascan Teak), various rosewoods (Dalbergia sp.) and Ebony (Diospyros perrieri). The bark of Prunus africana, a multipurpose species of the family Rosaceae, has been used at an industrial scale for more than 20 years for the manufacturing of drugs against human prostate gland diseases. However, the economic and social potential of Malagasy forests is far from being completely known. Since the end of the past century, many exotic tree species have been introduced to the country with variable success. Among the species which adapted very well, we find Pinus kesiya which has been planted on more than 80,000 ha, and Eucalyptus robusta which is mainly used for production of charcoal. For these major tree species, genetic improvement activities were initiated more than twenty years ago in collaboration with FAO, CIRAD-Forêt and more recently with INTERCOOPERATION, a Swiss agency for development cooperation. Many seed stands and cone banks were subsequently also established of Pinus kesiya, P. patula, P. elliottii, P. oocarpa, Eucalyptus robusta and E. grandis. More recently, seed orchards were established for provenances of several Acacia species (including A. mangium, A. crassicarpa and A. leptocarpa). ENVIRONMENTAL ISSUES IN MADAGASCAR Madagascar, once referred to as "The Green Island", is today known as "The Red Island". The Malagasy highlands are prone to considerable natural erosion, and this is aggravated by poor farming practices and frequent bush fires. This results in soil loss, decreasing fertility, increased run-off and silting of paddy fields in the lowlands, which are the main areas for food production. Very deep and extensive gullying is a major soil erosion problem. Deforestation According to FAO, the annual rate of loss of natural forest between 1980 and 1990 has been estimated at 135,000 ha. The main cause of deforestation is slash and burn agriculture for which there are few viable alternatives. National forestry authorities of the country have designed a network of protected areas to ensure the maintenance of the unique heritage of biological diversity, but the majority of the protected areas are situated in areas with high deforestation rates caused by strong population pressure. Furthermore, the increased demand for fuelwood around major settlements has put pressure on the surrounding forests. Developing a new forestry strategy Given these rather worrying developments, national and international institutions have become increasingly aware of the need to develop the institutional capacity and legal framework for forestry and the environment in general. Following the implementation of the Environment Action Plan, Madagascar is about to adopt a new forestry legislation and to launch its National Forestry Master Plan. These policy guidelines are based on participatory management and decentralisation of decision-making. Thanks to such measures, reforestation and associated demand for forest seed for planting programmes is accelerating. Table 1. Main species for which seed is produced by SNGF
"SILO NATIONAL DES GRAINES FORESTIERES" Mandate With the overall objective of increasing the contribution of the forestry sector to national development, a three-fold responsibility has been given to SNGF: production and distribution of high quality forest seeds by establishing, managing and locating seed sources of multipurpose species; research and development to improve the performance of widely-planted exotic and indigenous forest tree species; reforestation, carried out with due consideration to reproductive materials, marketing possibilities and monitoring and evaluation of planting success. Goal In the environmental context and in view of the many problems related to rural development, the SNGF aims to facilitate access to better forest tree seeds for reforestation and to provide support services which will result in more successful tree planting activities. Seed production and distribution Since 1988, SNGF has received assistance from the Swiss Cooperation to acquire the technical, logistic and managerial capacities which will enable the organization to carry out its mandate within the Malagasy forestry sector. After 8 years, the SNGF has consolidated its institutional basis and developed capabilities which enable it to meet the high and increasing demand for forest tree seed. In 1995, nearly 14 tons of seed were collected, of which 8,231 kg were sold to reforestation programmes on the island, and 4,000 kg (mainly palm seeds) were exported to Mauritius, Réunion Island and Australia. To successfully meet the demand, the SNGF has developed an integrated planning methodology for its forest seed production and distribution activities.
A Malagasy Catalogue of forest reproductive materials has been published and briefly describes 199 different seed sources which cover 9 main regions and subregions. The "Projet d'Appui au Silo National" (PASN) (Support Project to the National Seed Centre) was commenced in 1996 and will run until the end of 1998. It is anticipated that by that time the SNGF will be able to recover most of its operating costs from seed sales of forest and fruit tree species. In the meantime, priorities are to further strengthen SNGF's institutional capability and its impact on reforestation efforts in rural areas, and to strengthen its contribution to the Malagasy forestry sector. Research & Development The SNGF has a seed laboratory with basic equipment as well as a nursery which has a dual function to support research and production. These facilities are used to test and document seedlots and to develop new pre-germination treatments for lesser-known native species. More than 150 germination tests are conducted annually, mainly in the designated germination room. SNGF also collaborates with tree breeding programmes, which are mainly implemented by the Centre National de la Recherche Appliquée au Developpment Rural (CNRADR), in partnership either with PASN (pines and multi-purpose species) or with CIRAD-Forêt (hardwood species). These breeding programmes aim to produce genotypes of great plasticity which could be planted on a wide range of sites. Hardiness and vigor at a young age and better growth performance are characteristics which are selected for. Each breeding programme begins with an evaluation of provenance variation. This ensures that the programmes are soundly based, and can make best possible use of the existing natural variation. CNRADR/CIRAD-Forêt have opted for a multiple-population improvement strategy; a multi-location comparison and evaluation of this material; and seed production through open pollination following selective culling of the seed stand. More than 100 ha of seed production stands, including provenance seed stands, seedling seed orchards and clonal orchards have, to date, been established through these breeding programmes. In this latter category, an orchard initially comprising 160 clones of Pinus kesiya has been converted into an "elite clonal orchard", based on results from three progeny trials. Clones were selected through application of index selection. A third major area of research by SNGF is assessment of the genetic diversity of indigenous forest tree species and threats to their genetic resources. SNGF has endeavored to map the natural distribution range of Khaya madagascariensis and to carry out range-wide seed collections. The seed will be used to establish ex situ gene conservation stands, with special reference to tree populations under threat and at risk of genetic erosion. A study has been recently undertaken to identify the many native fruit tree species present in the forests of eastern Madagascar. Nearly 150 species with edible fruits have been identified. These are used by local people for food and medicinal purposes, and are usually for sale. Among the best represented families are Clusiaceae, Myrtaceae, Rosaceae, Euphorbiaceae and Passifloraceae. A new research programme aims to obtain more detailed information on some 30 native fruit tree species in order to develop domestication and propagation strategies for the most promising ones. Table 2. SNGF in brief
Towards reforestation Seed centres have a central role to play in identifying and disseminating information on forest tree species and other woody species of potential use in reforestation programmes. Accordingly, the SNGF is collating information and developing descriptive profiles for the main tree species recommended for reforestation in Madagascar. It has also prepared a leaflet aimed at facilitating the choice of species. A major species introduction and evaluation programme was initiated in Madagascar between 1950 to 1956. Approximately 500 hardwood species and 75 coniferous species were planted in arboreta at various forestry stations. The results of these tests have been carefully assessed and the SNGF is responsible for the dissemination of the results. In spite of the fact that a large number of the forest tree species have been tested to date, the increasing constraints on locating more suitable reforestation sites and the diversification of plantation aims have lead to the need for research for the identification of new, earlier un-used multipurpose species able to grow on the Malagasy ferrallitic highlands. |
An annually updated Collection Handbook is a useful guide for the seed collection team leaders. The handbook covers some 250 species and gives information on flowering/fruiting phenology, including seed maturation times, and the relationship between weight of fruit collected and seed quantities to be obtained. A descriptive database system, essential for integrating all information related to forest seed production and marketing activities, has been developed. This database forms the basis for the management information system of the SNGF.