KENYA FORESTRY SEED CENTRE
A PROJECT CONCEPT AND ITS CONTRIBUTION TOWARDS DEVELOPMENT

by

J. Albrecht & W. Omondi Oloo
GTZ - Forestry Seed Centre; P.O.Box 41607; Nairobi; Kenya
Kenya Forestry Seed Centre; P.O.Box 20412; Nairobi; Kenya

INTRODUCTION

Apart from their global, regional and local ecological importance, tropical and subtropical forests are of major importance in the economies of many developing countries. With their unique variety of flora and fauna, tropical forest ecosystems contain large reserves of biomass and timber, resources for feeding increasing human and animal populations, known and unknown basic materials for medicines etc. Moreover, forests fulfill important social and cultural functions.

A large proportion of the people in tropical and subtropical countries of the world live far below the poverty limit. They depend to a very high degree on woodfuel as the main energy source, on water from nearby natural sources, and on natural soil fertility for agricultural production. Trees and forests are therefore of paramount importance because they ensure and maintain the ecological balance. Sustainable development of a wide range of tropical countries in Africa, Asia, Central and South America can therefore not be achieved without the development of an organized forestry sector to support such efforts.

The situation of the forestry sector in Kenya may stand as an example for a number of developing countries. Its conditions can be described as follows:

• rapid population growth (3.8% p.a.);
• high dependance on woodfuel for the country's energy needs (80%);
• high percentage of arid and semi-arid lands (78%);
• high population pressure on forest lands;
• decreasing forest area;
• shortfall of all main forest and tree products at the end of the millenium;
• increasing number of threatened and endangered tree provenances and species.

Many efforts for implementing tree planting programmes have been made and ambitious targets have been set (the target for tree planting is 500 million seedlings p.a.), along with a reorientation towards the use of indigenous tree species. However, lack of knowledge in handling of indigenous tree species and lack of suitable tree seed have hampered these efforts.

The Kenya Forestry Seed Centre (KFSC) aims at the “Provision of certified, site suitable, high quality tree seed in sufficient quantities”. The project includes seed research, the development of suitable strategies as well as mechanisms aimed at control and protection.

HISTORY AND ORGANIZATION OF KFSC

Since the sixties, a small forestry seed unit within the Silvicultural Department of the Kenya Agricultural Research Institute had been existing. It provided mainly seeds of exotic industrial plantation species, such as cypress, pines and eucalypts.

In 1985, the Kenya Forestry Seed Centre was formed with the support of GTZ (Deutsche Gesellschaft für Technische Zusammenarbeit) on behalf of the Federal Republic of Germany. Today, KFSC is a Division of the Kenya Forestry Research Institute (KEFRI) which is based at Muguga, 25 km northwest of Nairobi, operating under the Ministry of Research and Technology.

KFSC has its Headquarters at Muguga with seed testing laboratories and seed handling and storage facilities. Eight Collection Centres are situated in different ecological regions of the country; moreover, a close cooperation with regional research stations of KEFRI is maintained (Figures 1 & 2).

According to its committment to quality tree seed and indigenous tree species, five major activities are covered and specified in the organization chart of the Centre (Figure 2):

• Seed Collection and Distribution;
• Seed Research;
• Training and Information;
• Technical Collaboration;
• Conservation of Genetic Resources.

KFSC has a countrywide mandate. Today, a stock of seed of about 220 tree species from more than 600 localities (provenances) is kept in store. Annually, seeds for raising 250 – 300 million seedlings are distributed.

Figure 1: Kenya Forestry Seed Centre: General Organisation

Figure 2: The regional organization of Kenya Forestry Seed Centre

QUALITY ASPECTS DURING THE IDENTIFICATION OF SEED SOURCES, SEED SURVEY, COLLECTION, HANDLING AND DISPATCH

Seed of high inherent qualities is considered to be the basis for adaptibility, stability and yield of forests and tree plantations. Quality tree seed as understood by KFSC does not only comprise external qualities like purity, freedom of insects and pathogens, but also the physiological and genetic aspects of viability, vigor and genetic variation. Moreover, the suitability of the site (provenance) is considered another factor of quality when it comes to provision of seed. Quality aspects are covered in guidelines which have been elaborated and which cover all stages and processes of seed research, procurement, production and distribution.

Ensuring quality during seed source identification
The provision of seeds has to reflect the different ecological conditions of the country. Seed sources must therefore be identified or if necessary established in all different ecozones. A seed zoning system, based on the similarity of ecological conditions, has been developed as a suitable expedient for a preliminary provenance differentiation (Albrecht and Braun 1993).

In accordance with the OECD Scheme (OECD 1976) seed sources in Kenya shall be selected and established in the categories “source identified, selected and tested”. In order to ensure a sufficient genetic variation in the seed lots, seed sources in natural forests must dispose of a size which allows the collection of at least 25–30 different trees with a distance of at least 50–100 m from each other. The recent setbacks with exotic species like Pinus radiata, Cupressus lusitanica and Leucaena leucocephala give reason to doubt that their occurrences 2 in the country do not dispose of sufficient genetic variation to cope with the new environment. A broad program for increasing the genetic variation of exotic tree species has therefore been initiated by the Seed Centre.

Flower and seed survey as a pre-condition for the procurement of quality seed
The distribution and frequency of male and female flowers in a seed source has an important influence on the genetic variation which is afterwards to be found in a seed lot. Hence, seed collection shall only be conducted after surveys regarding this aspect. Later, the development of the fruits has to be checked to determine the quality and maturity of the crop.

Ensuring quality during seed collection
As mentioned before, at least 25 trees with a distance of at least 50–100 m shall be included in a seed collection activity. Seed shall only be colleted from mature and healthy trees which fullfill the established standards of the phenotype of respective species. To ensure an equal representation of all genotypes, the same amount of seeds per tree shall be collected. Seed collectors have to collect and keep the seed separate by provenance. A clear and complete documentation and record-keeping is required.

Quality aspects during seed handling
Fresh seeds are subject to deterioration. Exposure to extreme heat, cold, humidity or desiccation, must be avoided to maintain viability and vigor. The handling, i.e. the separation of seeds from the fruits, the drying and storage of indigenous tree species frequently suffers from a lack of adequate information. Research is carried out on these aspects, and findings are transformed immediately into technical information leaflets which are distributed to users.

Seed Testing to Ensure Physiological and Genetic Quality
Seed testing of every seedlot follows, as far as possible with seeds of tropical tree species, the international rules (ISTA 1985) in order to ensure highest physiological seed quality and viability. The Seed Centre has given high priority to the genetic quality of seeds; isoenzyme studies are used increasingly to determine genetic differences between clones of seed orchards and seed production units. Currently experiments are carried out in Pinus and Cupressus seed orchards. Comparative tests are also running within natural and planted stands of two major indigenous timber species, see Table 1).

Ensuring Quality with Seed Distribution
The site suitability of forest reproductive materials is one of the most important factors for the practical forestry and agroforestry. In Kenya, there is an acute lack of information on the adaptation of species and provenances to varying sites. Moreover, there is often a lack of consciousness of this problem.

When seed is requested, the decision which provenance suits the specific site conditions best, is left to the Seed Centre. Thus, efforts have been made to develop a system of forest ecological zones which is used both in seed collection for provenance delineation, and in seed despatch for matching provenance with prevailing site conditions.

Ensuring Seed Quality in Tree Seed Multiplication
Many forestry and agroforestry projects in Kenya have started to establish seed orchards on their own. From the genetic quality point of view, most of them do not stand a control. Projects and other groups are therefore advised to follow the guidelines given below:

• The basic material for the establishment of the seed production unit must derive from selected seed sources or from seed orchards whose quality has been approved.
• The ecological conditions of the provenance or the area of origin of the basic material shall be known and documented.
• The site for establishment shall meet the requirements of the species in question in regard to all ecological conditions.
• Shape and site conditions of the stand shall be conducive to uniform pollination of all trees. Seed orchards shall have a minimum distance of 500m to a stand of the same species or a species which can form hybrids with the species in question.
• Seedling seed orchards shall be established with at least 1000 geotypes which derived from at least 30 different mother trees. The presence of at least 100 genotypes must be guaranteed during all stages of the orchard. Seeds shall be collected from at least 30 well distributed trees within the orchard and each tree shall be represented by the same amount of seeds.
• Clonal seed orchards shall be established with a minimum of 30 clones and at least 20 ramets each. At least 90% of the clones, with an equal number of ramets, shall be represented during all stages of the orchard. Seed collection shall be conducted only after an evenly distributed flowering of at least 15 clones has been observed. Each clone must be represented by the same amount of seeds.

TREE SEED RESEARCH AT KFSC

The focus of interest in exotic tree species (Cupressus lusitanica, Pinus spp., Eucalyptus spp) until only a few years ago created an immense backlog in the knowledge about indigenous tree species, particularly in phenological behaviour, seed physiology, extraction, drying, storage and pre-sowing treatments. Table 1 shows species and research activities at Kenya Forestry Seed Centre since the beginning of the project in 1985.

Phenological Observations
Phenological observations are carried out throughout the country and are facilitated by the regional structure of KFSC (Figure 1). The aim is the development of flowering and seedling calendars and, in conjunction with research experiments, the determination of a timing of seed collection which guarantees storability and high germination percentage.

Timing of Seed Collection
Experiences with several species suggest a rapid drop of viability of stored seeds when they are collected overmature, e.g. fallen to the ground. Germination experiments are carried out with seeds collected at different stages of fruit maturity, under different storage conditions.

Pre-Germination Treatments
Pulpy fruits create problems not only for extraction but also in germination. Experiments with several species have shown a significantly higher germination rate when the pulp is removed while fresh.

Extraction methods are tested in order to diminish impurities and damage to seeds. Methods applicable under field nursery conditions have been developed for a number of species.

All kinds of dormancy are to be found or supposed to occur within the enormous variety of Kenyan tree species; this inhibits uniform and fast germination. Species new to the seed science are tested in comprehensive screening experiments.

Storage of Recalcitrant Seeds
Many of the important tree species in Kenya are considered to be recalcitrant. The loss of viability with decreasing moisture content and limited storability, are a special challenge for the researchers. Storage of seeds is inevitable for species which do not seed regularly, or which produce seeds when the sowing season is already past.

Table 1: Research Activities at Kenya Forestry Seed Centre 1985–92

Establishment of provenance/progeny trials
A large number of provenances/progenies from the natural distribution area of species used, is required for trials which will be replicated at least 20 times in randomized single/two tree plots. The seeds must derive from a sufficient number of trees/families per provenance to ensure high genetic variation. At least three different sites within the species' ecological tolerances have to be chosen for the establishment of the trials. The identity of provenances/progenies must be retained at all stages of the trials.

Important characteristics are assessed periodically until there is a clear picture of the performance of the provenances/ progenies under the different site conditions. This is the moment when particular provenances or progenies can be chosen for fresh imports for the establishment of seed production units.

Basically, all important exotic tree species which have an assumed narrow genetic base and which have been haphazardly introduced into Kenya are candidates to be included in this programme. Trials with six exotic tree species of major importance in Kenya have been established, others are awaiting establishment. In cooperation with the Tree Improvement Programme of KEFRI, indigenous species including those under threat of extinction shall also be included in the experimental programme.

INFORMATION AND TRAINING

Research findings are published in relevant national and international media. Practical advice is given for different levels through KEFRI's “Technical Notes” series, the Forest Extension Service's “Rural Forestry News Letter” and KFSC's “Tree Seed Information”.

Training in tree seed collection and handling has become a major task of KFSC in recent years since seed collection activities are carried out by an increasing number of national and local groups, projects and organizations. KFSC has developed into a nationally and internationally recognized training institution in tree seed technology.

Special courses are offered in

• seed source identification and establishment of seed production units
• seed collection techniques including tree climbing
• seed processing and storage
• seed testing
• documentation
• seed policies and management of seed centres.

TECHNICAL COLLABORATION

Besides the general information disseminated by the Centre, assistance is given for instance in establishment of seed production units and seed storage facilities. The Centre collaborates with national and international institutions and organizations (FAO, IUFRO, ISTA, ICRAF, UNDP, etc.) in the field of research, training and information.

KFSC has drafted and produced the “National Regulations for Forest Reproductive Material”, which aim to promote stability, sustainability, productivity and genetic variation in forestry and agroforestry by ensuring the provision and use of quality forestry tree seed and the protection of seed sources, as well as to control the import and export of tree seed.

Genetic quality in tree seeds is recognized and highlighted. Seed collection has to follow minimum rules as regard to seed sources and techniques. The trueness of name and the physiological quality of forest reproductive materials has to be ensured in accordance with international rules (ISTA, OECD). The control of all related activities lies in the hand of experts (the Seed Centre); it includes the registration of commercial seed collectors and dealers.

CONSERVATION OF GENETIC RESOURCES

Nearly 100 woody species are considered to be endangered in Kenya. Out of these, KFSC has - as a first step - identified 10 species with both ecological and economic value. Measures for the conservation of the remaining genetic resources of these species and provenances comprise:

• the protection of the remaining populations (in cooperation with the Forest Department)
• the collection of seeds
• the establishment of conservation stands
• the long term storage of seeds
• the development of methods for vegetative propagation (in collaboration with other KEFRI Divisions).

Cooperation was recently started with the Plant Conservation Unit of the National Museums of Kenya in the above activities.

CONCLUSIONS

The use of seed of high inherent qualities is a pre-condition for the success of plantations as regards to survival, resistance and yield. The high degree of dependence of developing countries on direct and indirect forest and tree products and the increasing number of activities carried out by a growing number of organisations with high motivation but insufficient technical knowledge, raise the necessity of giving special attention to the procurement and supply of high quality tree seeds.

• The establishment of Tree Seed Centres is considered to be an important contribution to the development of forestry and its connected sectors.
• Seed research for indigenous tree species has to be given high priority in order to contribute to the conservation of the national heritage.
• Seed source selection and establishment as well as seed collection have to follow rules which ensure a high genetic quality.
• Seed provision has to be regulated within the context of international rules in order to protect user and producer.
• Site suitability is an important factor and places high responsibilities on seed provision for correct species/provenance site matching.
• Seed testing shall include aspects of genetic quality by using the newest biotechnical methods.
• Training in seed collection, handling, processing and storage is an important indirect means to ensure quality in tree seed.

Forest Genetic Resources Information no. 21. FAO, Rome (1993)
Manucript received May 1993