by
Agnete Thomsen and Oudara Souvannavong
Forest Resources Division
Forestry Department
FAO
BACKGROUND
Neem, Azadirachta indica A. Juss. (Meliaceae), is an evergreen, multipurpose tree native to the Indian Sub-Continent and South-East Asian countries, where it has been traditionally used for centuries. The species' adaptation to hot and dry climates has made it one of the most commonly planted species in arid and semi-arid areas, both within its natural range and outside of it, in Africa, Latin America and the Caribbean. In the African Sahel, neem is mainly planted as shade tree and in windbreaks, although production of fuelwood by pruning and use of various parts of the tree in local pharmacopoeia are also important. In its natural range, particularly in India, products derived from neem have been traditionally widely used for centuries for many medicinal and pest management purposes. Extracts of neem oil and chemicals derived from neem for industrial uses are gaining more and more attention worldwide.
Despite the widespread use of neem, programs for the evaluation and improvement of the genetic resources of the species were not had, until recently, not been carried out in a systematic way, mainly because of seed storage and transport problems which placed a serious constraint on seed collection and transfer. As a result, the genetic material presently used in plantations is generally thought to have been originally chosen in a random manner, and their genetic base is frequently likely to be very narrow, particularly in countries located outside the natural range of the species. Neem decline is presently affecting many Sahelian countries; it is likely to be caused by a number of interacting environmental and genetic factors (including adverse effects of the narrow genetic base used, i.e. lack of genetic variation and subsequent inbreeding), possibly aggravated by pathogens.
In the first Consultation on Neem Improvement, Bangkok, 18–22 January 1993, participants from 20 countries, including the main countries of the natural range of the species, agreed to undertake an international neem improvement programme.
Pilot activities was undertaken in a preliminary phase (1993–1994), to test and improve procedures for provenance seed collection, handling and exchange for international trials. In 1993, a total of 23 provenances were collected in India, Nepal, Pakistan, Sri Lanka and Thailand, and dispatched to 14 collaborators in 10 countries of Africa, Asia and Latin America. The Second Consultation on Neem Improvement, held in Jodhpur (India), 28th February -4th March 1994, examined the results of these pilot activities which confirmed that neem provenances can be successfully collected and exchanged for international trials, provided optimal procedures for seed collection and handling are carefully followed, and despatches to trial sites are quick and well coordinated. Based on these findings it was decided to undertake a full scale programme (“the International neem Network”). The Network is coordinated by a panel formed by CIRAD-Forêt (France), DANIDA Forest Seed Centre (DFSC, Denmark), FORTIP and FAO. Global coordination is entrusted to FAO to facilitate inter-regional cooperation and exchanges of information and genetic material.
The long-term objective of the International Neem Network is the improvement of the genetic quality and adaptability of the neem planted and its utilization, throughout the world, as a contribution to development in the countries concerned, and in particular in meeting the needs of rural people. To meet the objectives of the International Neem Network two groups of activities are foreseen, the main one being provenance exploration, collection and testing, and the second one consisting of four supportive research components.
PROVENANCE EXPLORATION, COLLECTION AND TESTING
In 1994 additional pilot collections were carried out in India, Myanmar, Senegal, Bangladesh, Sri Lanka and Thailand. In addition, a regional training course on neem collection, handling and despatch was held in Coimbatore in June 1994, organized within the framework of the Network.
Exploration, identification and documentation of seed sources are under way in each country in the natural range and among landraces. The data on provenance/population characteristics will eventually be transferred to a database. These data will be the basis for the selection of seed sources to be included in subsequent international provenance trials. A meeting of the coordinating panel is planned in December 1994 to elaborate the specific plan for seed collection and distribution. Seed collection for the full scale international provenance trials will take place in 1995 and trials will be established in 1996 according to an agreed “Trial Establishment Manual”. The assessment of the international trials will also be done following common procedures and schedules. In a further phase, ex situ conservation stands and seed production stands will be established to ensure the availability of seed of improved genetic and physiological quality, and to conserve some of the provenances which have performed well in the international provenance trials.
SUPPORTIVE RESEARCH
The supportive research to be undertaken by the network collaborators has the following four components:
Phenology
Seed physiology/technology
Genetic diversity/reproductive biology using genetic markers
Variation in chemical compounds
THE NETWORK ORGANIZATION AND PRINCIPLES
The following cooperation principles for the network were discussed and approved at the Second International Consultation:
Free availability to all network collaborators of seed for research purposes on an exchange basis.
Adaption of standardized trial designs and standardized evaluation procedures.
Free availability to all network collaborators of trial and research results.
Provenance seed collection/handling/despatch for trials included in the programme will be carried out by cooperating countries and support will be provided or sought by Network members.
Complementary studies (phenology, genetic diversity/reproductive biology, seed physiology) will be undertaken through specific research projects discussed and approved by the network collaborators. Each project has a coordinator and will be presented for funding to interested agencies, as a research module supporting the neem improvement network programme.
Each network collaborator can be involved in the various activities according to interest and capability.
Each participating country has a national focal institution (NFI) which coordinates the network activities at the national level.
The Network is operating under the coordination of a Panel formed by representatives of NFIs of 3 participating countries, plus CIRAD-Forêt (France), DANIDA Forest Seed Centre (DFSC, Denmark), the UNDP/FAO Regional Tree Improvement Project (FORTIP), IPGRI and FAO. Overall coordination is entrusted to FAO.
The initial group of network collaborators (representing 23 countries) will be progressively open to other collaborators who adhere to the above principles.
Forest Genetic Resources No. 22. FAO, Rome (1994)
