by
Dr. D.G. Nikles
Department of Forestry
Brisbane, Queensland, Australia
ABSTRACT
Previous papers by the author on proposals for international co-operation in the genetic improvement of Pinus caribaea Morelet are briefly reviewed, and the earlier plans are outlined and updated.
It is proposed that a co-ordinator for an international co-operative breeding programme be attached to an Australian forest research institution to implement the plan. The co-operative improvement strategy recommended involves pooling genotypes already selected in many countries; producing full-sib progeny; establishing progeny at key test centres; and sharing clones, seeds, and plus trees selected in each generation. The plan is patterned generally on the highly successful international breeding programmes for wheat, maize and rice.
Introduction
Several aspects of world-wide reforestation programmes and genetic improvement projects with Pinus caribaea Mor. var. hondurensis Barr. and Golf. were discussed by Nikles (1971, 1973a), including planting programmes, seed sources, the need for genetic improvement of planting stock, the scope for and potential value of international cooperation in tree breeding, and proposals for co-ordination of the several small national projects that have been started to develop local, improved breeds. All of the independent improvement projects are attempting to secure better stem straightness, a reduction in the percentage of foxtailed trees, and maintenance of the great vigour of the variety as well as gains in other traits of local importance. Genetic gains in all these traits (and others) have been demonstrated in progeny studies in Queensland, Australia, and they are being achieved operationally there through mass selection, that is selecting “plus” trees and establishing isolated clonal seed sources (Nikles 1973b).
A limited amount of international co-operation has begun, mainly through bilateral arrangements between the Department of Forestry, Queensland, Australia and several other institutions involving the export of scions from Queensland and exchange of wind-pollinated seed (Nikles 1973a, 1973c). However, there is opportunity for greatly extending international co-operative breeding work through broadened sponsorship and improved co-ordination. A plan for such a programme is presented briefly in this paper. It is basically a summary of proposals made by Nikles (1973a), with updating of information.
Current Genetic Improvement Work with Pinus caribaea var. hondurensis
1. Selection of plus trees and establishment of clonal seed sources for genetically improved planting stock are current in at least a dozen countries.
2. Almost all the plus trees selected so far are in plantations derived from seed of the isolated and most northerly occurrence of the variety, that is on the Mountain Pine Ridge of Belize (formerly British Honduras).
3. All of the genetic improvement projects, with the exception of that in Queensland, Australia, involve use of small numbers of selected clones (about 10 to 40 clones), and they do not include plans for controlled crossing to develop progeny populations (for recurrent selection) that are broadly based and of very high quality genetically. It has been realised recently by tree breeders in the temperate regions, where tree breeding work has a longer history than in the tropics, that multi-generation breeding programmes should be based on large numbers of initial selections (several hundred), and that appropriate mating and field designs should be employed to generate and test large numbers of progeny (Burdon and Shelbourne 1972, Namkoong 1972). It is clear the strategy of many current tree improvement programmes with P. caribaea var. hondurensis requires review and modification in the light of modern knowledge. Such a review and replanning of the existing programmes offers the opportunity to plan for international co-operation in a multi-generation breeding programme.
4. Clones from plus trees selected in Queensland have now been established in clone banks or seed orchards at several other places, including Northern Territory of Australia, Papua New Guinea, Fiji, Malaysia and Central and East Africa. The successful establishment of these Queensland clones in several countries demonstrates that this procedure could be used to develop seed orchards in countries where sufficient local selections are not available. (Clonal stands begin to produce significant amounts of seed by ages 8 to 10 years in Queensland). These Queensland and local clones could also be used in some cases for controlled crossing as described below.
5. Progeny from bulked seed from Queensland's improved seed sources or individual, wind-pollinated seed lots from selected trees in Queensland and Fiji have been established in several other countries. Thus seedling seed orchards could be established where needed if numerous seed lots of high genetic quality were available. (Seedling stands begin to produce significant amounts of seed by ages 10 to 12 years in Queensland). Such seedling stands would also offer opportunity for selecting plus trees locally within the introduced families for use in local clonal seed orchards.
6. The total number of high-quality plus trees of P. caribaea var. hondurensis selected through the tropics and sub-tropics probably exceeds 300 (Nikles 1973a). Most of these selected trees are in plantations of the Belize, Mountain Pine Ridge provenance. Such a total number of selected genotypes would provide an excellent base for a co-operative genetic improvement programme, and it could be secured by pooling these select gene resources through judicious transfers of pollen, scions and seed. Well-planned crossing of the members of this large breeding population, establishment of progeny trials at several key test centres throughout the tropics and sub-tropics, and development of second-generation seed orchards would enable much greater genetic gains to be achieved and broader genetic bases to be maintained than independent breeding could do.
7. It will be about 10 years or more (see point 11 below) before a substantial number of plus trees may be found within plantations of provenances other than Belize, Mountain Pine Ridge. Hence genetic improvement of the variety will most likely be by recurrent selection within the Mountain Pine Ridge populations for a decade or so at least.
8. Sustained controlled breeding work to produce a pedigreed second generation for future selection is confined to Queensland at present, where some 120 full-sib families have been produced, but from only about 40 parents. Full-sib families have been planted since 1963. (In fact, some second-generation plus trees have been selected within progeny trials and cloned in a seed orchard together with first-generation selections (Nikles 1973b)). More than 100 clones of non-pedigreed, first-generation plus trees have been established, and it is anticipated that this base will reach about 200 within a few years when the searching of plantations from imported and bulked local seed is wholly superceded by pedigree selection. There are two field stations where tree breeding work with P. caribaea var. hondurensis is carried out (at Byfield and Cardwell) by trained technicians. These facts show that a good genetic base and organization for further breeding work is established in Queensland. With additional resources of man-power and equipment, the local breeding work could be extended to include activities connected with an international co-operative breeding programme.
9. Seed from controlled single-crossing rather than from wind-pollination or poly-crossing of the selected parents should be used in any international co-operative breeding programme because of the higher genetic gains and knowledge of the full pedigree associated with selection within full-sib rather than half-sib families.
10. There is evidence to suggest that within the group of plus trees selected in each country, a few genotypes will be found whose families show high and stable performance (for the selection criteria used) when tested over a wide range of environments. Thus by pooling all selected trees available, mating them and testing their progeny co-operatively, and reselecting for stable, high performance (among the parents or in the progeny of desirable parents), it is likely that greater progress will be made than by breeding independently.
11. International provenance trials, sponsored by C.F.I., Oxford, of up to 16 provenances from throughout the range of P. caribaea var. hondurensis have been planted in many countries since 1972, and small conservation - selection stands of several provenances are being established in a few of them. These experimental and conservation - selection stands can be expected to provide additional plus trees in the future, especially if it is found that some provenances are superior to that of Belize, Mountain Pine Ridge. Depending upon the degree of superiority of any of the new provenances, future breeding work in the variety could be by the development of synthetics through provenance crossing, or by recurrent selection within provenances. But present uncertainty, as to the best breeding procedures for P. caribaea var. hondurensis that will be devised ultimately, should not prevent initiation of a co-operative breeding project based on the best material presently available.
Plan for Co-operative Genetic Improvement of P. caribaea var. hondurensis
Two aspects must be considered in proposing a genetic improvement programme for P. caribaea var. hondurensis based on international co-operation: technical aspects, namely short-term projects and long-term projects; and organization of the programme from a central agency, preferably an institution having staff with expertise in this field.
Short-term Projects
The central agency of a co-operative programme could assist individual countries in the early establishment of local seed sources by arranging (where necessary) the provision of scions or seedlots for establishing clonal or seedling seed orchards. The agency would have to secure and build up a supply of seed lots for this purpose, and an inventory of clones available for export to recipient co-operators. Such seed sources could be expected to come into production 8 to 12 years after establishment. Meanwhile seed supplies required for current reforestation projects would have to be secured from natural stands and other countries with older exotic plantations, as at present. The central agency could encourage countries having plantations of or nearing seed bearing age to establish thinned seed production areas within them for the production of seed for export. It should take responsibility for certifying such areas.
(In planning clonal seed orchards and seedling seed production areas in Queensland, account has been taken of the seed export market. Considerable amounts of selected seed should be available for export from Queensland by the mid 1970s).
Long-term Projects
The basic requirements for securing significant genetic gains over several generations are to form large breeding populations and large progeny populations therefrom, and to retain a relatively small group of proven parents for seed production in successive seed orchards. In the case of P. caribaea var. hondurensis a large initial breeding population of about 300 plus trees can be secured most effectively by pooling the best genotypes that are being chosen in the numerous, presently independent selection programmes of several countries.
The progeny population for the next stage of selection should be developed by employing a simple mating scheme, such as double-pair crossing, and establishing the resultant 300 full-sib families in replicated trials planted by about 8 key co-operators (Nikles 1973a). A similar strategy was recommended by Shelbourne (1973), following his organization of a co-operative gene pool of 319 almost wholly half-sib families of Pinus radiata, for any future similar endeavour.
The bulk of the controlled crossing could be carried out in Queensland, if assistance were provided in the form of technical manpower and equipment. Using pollen taken from 100 plus trees selected in other countries, pair crosses could be made using flowers on the 100 clones already established in Queensland. Additional crossing could be done (later) in Queensland and elsewhere (depending on the availability of pollen and clones with ovulate strobili) in order to secure about 300 families from a breeding population of about 300 plus trees.
Within the full-sib progeny plantations of some 300 families established at the 8 or more key test centres, second-generation selections could be chosen for
establishing new clonal seed orchards locally, and
forming a new, large breeding population for another phase of mating and recurrent selection.
As the co-operators increased their expertise, more complicated mating and selection techniques could be considered.
Organization
Such an international co-operative breeding programme would require a co-ordinator attached to the central agency on a full-time basis. The work would be planned on the pattern of the highly successful international crop breeding projects with wheat, maize and rice. The main areas of work of the central agency would be as follows:
Assessing the scope and arranging membership of the co-operative.
Assisting co-operators with establishment of interim seed sources, as described above under the heading “Short-term Projects”.
Planning and arranging the execution of the work listed above under “Long-term Projects”.
Assessing research needs and planning action thereon.
Conducting supplementary training of technical and professional personnel of the co-operating countries as required.
Assessing needs and opportunities for extending the co-operative programme to include, for example, P. caribaea var. bahamensis.
LIST OF REFERENCES
Burdon, R. and C.J.A. Shelbourne, 1972. Breeding populations for recurrent selection: conflicts and possible solutions. N.Z. Jl. For. Sci. 1 (2) : 184–93
Namkoong, G. 1972. Foundations of quantitative forest genetics. The Government Forest Experiment Station of Japan.
Nikles, D.G. 1971. A proposal for international co-operation in the breeding of certain conifers, with special reference to Pinus Caribaea Mor. Paper presented to Symposium on Selection and Breeding to Improve some Tropical Conifers, 15th I.U.F.R.O. Congress, Gainesville, Fla., March 1971, 26 pp. (Manuscript distributed to Symposium participants).
Nikles, D.G. 1973a. A proposed breeding plan for improvement of Caribbean pine (Pinus caribaea var. hondurensis Barr. and Golf.) based on international co-operation. In: Burley, J. and D.G. Nikles (eds.), 1973. Selection and Breeding to improve some Tropical Conifers. 2:364–87. Commonwealth For. Institute, Oxford.
Nikles, D.G. 1973b. Progress in breeding Pinus caribaea Morelet in Queensland, Australia. In: Burley, J. and D.G. Nikles (eds.), 1973. Selection and Breeding to Improve some Tropical Conifers. 2:245–66. Commonwealth For. Institute, Oxford.
Nikles, D.G. 1973c. Establishment of a co-operative progeny trial of Pinus caribaea Mor. var. hondurensis Barr. and Golf. in Australia and Fiji. In: Burley, J. and D.G. Nikles (eds.), 1973. Proceedings of a Joint Meeting (of I.U.F.R.O. W.P.s S2.02.8 and S2.03.1) on Tropical Provenance and Progeny Research and International Co-operation. Commonwealth For. Institute, Oxford.
Shelbourne, C.J.A. 1973. An international co-operative second generation family experiment in Pinus radiata. In: Burley, J. and D.G. Nikles (eds.), 1973. Proceedings of a Joint Meeting (of I.U.F.R.O. W.P.s S2.02.8 and S2.03.1) on Tropical Provenance and Progeny Research and International Co-operation. Commonwealth For. Institute, Oxford.
FAO PANEL OF EXPERTS ON FOREST GENE RESOURCES
Rome, 6 – 10 May 1974
Third Session
Section I Progress since 2nd Session of Panel (March 1971)
Regional/country statements by individual members
International coordination
Section II Use of FAO Regular Programme Funds 1974/75
Revision of priorities (type of activity)
Revision of priorities (species and provenances)
Allocation of funds to institutes with operational responsibility
Section III Methodology of Conservation of Forest Gene Resources
Consideration of current short-term UNEP/FAO project
Section IV A Global Programme for Forest Gene Resources
Action needed
Estimated cost
Sources of funds
Operational responsibility
Needs for coordinating staff
Priorities for action within global programme
Section V Relationship between Forest and Crop Plant Genetic Resources
Section VI Related Activities
Third World Consultation on Forest Tree Breeding
Others
Section VII Miscellaneous
Membership of Panel. Time and place of next session
Any other business.
(UNEP Project No. 0604-73-003)
Summarized description of project
Appointment of high-level consultants to prepare scientific guidelines as to the methodology of conservation of forest genetic resources. This would cover conservation (i) as natural stands in situ, (ii) as seed or other kind of propagules (iii) as artificial stands ex situ. The report would include recommendations as to suitable sites and countries for the establishemnt of provenance conservation stands of major species. The report to be produced will be designed to provide a basis for future UNEP action in the field of the conservation of forest genetic resources and will contain proposals for an action programme.
Outline of final report
PART I GENERAL PRINCIPLES
1. Biological Background
Breeding system, ecological and genetic variation, static and dynamic conservation (stability v. evolution), their effects on methods of conservation.
2. Practical Constraints
Policy, legislation, public opinion, finance, staff, training and research, effective measures for control.
PART II SPECIFIC CASE STUDIES
A. As Living Trees
3. Case study 1 | Pinus banksiana and Picea glauca |
4. Case study 2 | Californian conifers |
5. Case study 3 | Central American pines |
6. Case study 4 | Tropical hardwoods |
7. Case study 5 | Eucalypts |
8. Case study 6 | Ex situ conservation/selection stands in Africa |
B. As Seed/Propagules
9. Possibilities and limitations of storage in controlled conditions
PART III CONCLUSIONS
10. Priorities for research and for international action
11. Summary of conclusions and recommendations
by
W.G. DYSON, E.A.A.F.R.O.
1. Introduction
Tree species will usually be conserved for one or more of four reasons:
Present Economic Value
Production of timber or other forest produce, soil and water conservation, as shelter for dwellings and domestic stock, amenity value in parks gardens, etc.
Future Economic Potential
The number of tree species in the world is large (tens of thousands) but few (hundreds) are in regular economic use. New uses may be found for presently unutilized species.
Scientific and Educational purposes
As in nature reserves, botanic gardens, etc.
Aesthetic Reasons
For scenic and artistic purposes, because it is widely felt that the wonders of nature should not be allowed to become extinct and, surprisingly but commonly, because of a desire to preserve or recreate an idealized concept of natural woodland as it was thought to be, say, 100 years ago.
Species conserved for present utility are in little danger of extinction; so long as man wants them, he will cultivate and tend them. This applies to a number of trees regarded as “endangered” e.g. Araucaria excelsa of which the wild populations are endangered, but the species is not because of persistent cultivation in parks and gardens. Cupressus cashmeriana is an example of a species of which the wild populations have been entirely lost, but the species survives in cultivation.
The problem of conservation is most serious for the great majority of tree species which are little known, except to taxonomic botanists, and which have no conspicuous economic utility for man. Since the number of such species is large (tens of thousands), the writer has argued (1968, 1971) that the only feasible method of conservation is in their natural habitats in substantial blocks of forest set aside as nature reserves. Such nature reserves would, of course, also conserve many other plant and animal species besides forest trees.
It may be noted here that, in the long run, no species can survive unless it either adapts to meet the competition (ultimately becoming a recognisably different species) or emigrates to avoid the competition, or the competition declines. In nature direct competition between species only rarely proceeds to complete extinction of one of the competitors; more usually adaptation gradually occurs to permit the species to live alongside one another in a given environment often to their mutual advantage. In discussing conservation, we are concerned with direct competition between man and wild species. But man is increasing his population so rapidly and increasing his command over the environment so fast that wild species have no chance to adapt sufficiently quickly to avoid extinction. The fear of the conservationists is that man can't adapt his habits quickly enough to recognise the mutual value of wild species before they are extinguished by his competition. Proposals to conserve tree and other species in nature reserves can do no more than isolate them from direct competition with man and give them a chance to continue to survive amongst competitors they have been able to withstand upto the present day. Nature Reserves provide no guarantee of future survival and, in the long run, they will only persist to the extent that man learns to regard them as useful to him.
Already in 1974, competition for living space by man and his domesticated species against wild species is severe and nature reserves to conserve tree and other species must be as small in area as is consistent with the object of conservation. The aim of the present notes is to discuss the minimum area of nature reserve necessary to conserve tree species in situ.
2. Genetic Considerations
In conserving a “species”, it is necessary to maintain not only the minimum population that will breed, but also a substantial part of the natural variation among individuals of the species as we know it. Variation is preserved mainly by recombination of existing genes in the population at successive sexual reproductions, but may also be increased by mutation or byimmigration of individuals from other populations having different gene sets. Since genes appear to assort themselves basically in accordance with the laws of chance the effect of population size on the assortment of genes (and hence variation) can be calculated mathematically and has been the subject of a number of detailed studies. It is usual to postulate an idealized population in which immigration, mutation or selective removal of genotypes does not occur. In a large fully interbreeding population, the gene frequency remains constant from generation to generation in accordance with the Hardy-Weinberg Law (Hardy, 1908; Stern, 1954). If breeding is not at random or the population is small the Hardy-Weinberg equilibrium can't be maintained and inbreeding leads to progressive fixation of gene loci homozygously. Further, chance, non-random assortment of genes in a small population can lead to definite directional shifts of gene frequencies and may result in fixation of disadvantageous characters where these are not removed by selection. These effects have been studied mathematically in great detail by Sewall Wright (1931, and many subsequent papers) and must be taken as proven for the idealised populations considered. They have also been demonstrated in laboratory populations of animals which were reared in conditions simulating the idealised population. Thus Wright & Kerr (1954) showed that of 108 lines of Drosophila melanogaster maintained by using 4 males and 4 females per generation, 95 had become fixed for the wild-type allele by the 10th generation, 3 of the 108 had become fixed for the mutant allele “Bar-eye” and only 10 remained unfixed. Similarly Falconer (1964) shows the progressive increase by genetic drift of the frequency of the gene “Agouti” from 0.5 to 0.9 in a line of mice maintained by using 6 pairs of parents per generation.
Sewall Wright using formulae derived by Fisher (1930) calculated that gene fixation would be important in populations of less that 81 individuals, but believed this to be far too small and Fisher's formulae consequently to be in error. Using his own formulae he asserted genetic drift can occur in completely isolated populations up to 250 000 assuming a mutation rate of about 10-6.
The writings of Sewall Wright and Fisher are extremely difficult for the non-mathematician to follow but Falconer (1964, p 78) concludes that, where the effective number of breeding individuals is about 20, a large amount of local differentiation may be expected to occur, a moderate amount if the effective number is about 200 and that it will probably be negligible in populations of about 1000 breeding individuals.
The effective number of breeding individuals is always a good deal less than the actual number of individuals in the population but has been determined experimentally (with laboratory animals) as ranging from 56 to 95 percent of the actual numbers.
Experimental verification of the size of the effective breeding population which will avoid inbreeding in natural populations is very difficult, because one can seldom estimate precisely the effects of mutation migration and selection which always occur in nature, but are ignored (or inserted at realistic values) in mathematical models. Work by Lamotte (cited in Falconer, 1964) suggested appreciable local differentiation appeared in populations of 3 000–10 000 snails and much more in smaller populations. This conclusion was, however, disputed by Cain and Sheppard (1954) who maintained that the differentiation observed was dependent more on selection than on population size. Ford (1964) working with butterflies demonstrates that selection will over-ride genetic drift in populations as small as 10 breeding individuals if the selective advantage for a given gene exceeds 20 percent, and produces much evidence to show that selective advantages of this order are common in butterfly populations.
From the above it would seem that a freely interbreeding population of animals where the effective number of breeding individuals exceeds 100 should be sufficient to avoid the ill effects of in-breeding. The actual number would need to be at least 200 to allow for non-breeding individuals and because not all possible pairs will actually breed together.
It is probably safe to assume that this estimate of a minimum “safe” population of 200 individuals estimated from animals which are compulsory out-breeders is applicable to forest trees. Many species of higher plants survive with only very infrequent out-crossing, or even as clones. Briggs and Walters (1969, p. 134) suggest that there is a selective advantage for autogamous species which live in an open environment such as annual weeds of cultivation, but that species living in more complex plant communities need outbreeding systems to ensure a continued supply of variation to survive complex environmental changes. Because they can't move to seek a mate, most higher plants retain the ability to self fertilize if out-breeding fails, and a minimum population “safe” for compulsorily out-breeding animals should be adequate for the more versatile plants.
Clearly there will be a great advantage if two or more populations of a species, each exceeding the minimum “safe” size, are preserved separately so that, if any tendency to disadvantageous in - breeding is observed, individuals from another population can be introduced to correct the gene frequencies. In nature reserves such deliberate correction (as is done by stock breeders when they “introduce new blood”) would probably be seldom, if ever, required. Very infrequent immigration would be sufficient if our minimum population is correctly estimated.
It has often been observed that variation of a plant species is greater at the centre of its range than at the extremes (see for example Agnew, 1968) and that the less variable marginal parts of the population are specialised to meet more extreme conditions of the environment. For future utilization of the species it is desirable to have samples of the variable central part of the population and also of the more specialized types. Thus Edwards (1963) when considering seed collection for provenanc trials recommended that at least three parts of the range be sampled. The writer (1968) has recommended that a tree species should be preserved in five parts of its range, one central representing optimum growth and variation, and four peripheral representing extremes of specialization to environmental limits (altitude, latitude, rainfall etc.).
Except with sparsely distributed species the preservation of two to five areas containing 200 individuals should not present insuperable administrative and political difficulties.
3. Ecological Considerations
If we say that mature trees require about 100 m2 of growing space, 2 ha of a closed stand of a single tree species should contain the 200 individuals considered necessary on genetic grounds to preserve a tree species. But pure stands of trees are rare in nature and, while forests in the north circumpolar belt are simple floristically, equatorial forests are extremely complex mixtures of many species and a correspondingly larger area would be required to preserve the minimum 200 individuals of each component species.
Little (quoted in Dyson 1965) has estimated that there are about 20 tree species in Alaska and over 2000 in Costa Rica. Since mature trees do not vary very greatly in size, we may expect that on average the frequency of any one species per unit area in equatorial forest would be about 100 times less than in the northern conifer forests. Thus where an area of 2 ha might be sufficient to conserve one species in northern forest, 200 ha would be required for species in tropical rain forest and, if there were 2000 species to be conserved, 400 km2 of rain forest would be required to be set aside.
In practice a much larger area would be required even in the comparatively simple northern forests. Pure stands of one species usually only occur as a seral stage in natural forest following some environmental disaster such as fire, storm or land slide. Thus there will always be a mixture of several tree species at different frequencies and the area reserved will need to be large enough to contain 200 individuals of the least frequent species.
A further complication arises from the interdependence of one species upon others in the forest community. The extreme case is that of a parasite, like sandal wood, which can't be preserved unless a population of the host species is also maintained for the parasite to live upon, but many tropical species survive only in deep shade in multistorey forest. Other species are essentially pioneer species and colonise open land, but are slowly replaced by more shade tolerant species as a forest canopy develops. In order to preserve such species the area of forest set aside as nature reserves must be large enough for part of it to be cleared from time to time (preferably by natural causes) so that pioneer species can regenerate themselves.
Considerations such as the above, and the large number of species involved, lead to the conclusion that it will not be possible to conserve tree species individually, except for a very few special cases where the population is known to be very small and isolated. The only feasible method of conserving the great majority of species lies in setting aside substantial blocks of natural forest as nature reserves. The same conclusion is reached by the animal conservationists for, while it may be possible to make special arrangements to conserve the Arabian Oryx or White Rhinoceros, the vast number of known insect species defies any attempt at individual conservation.
In most parts of the world the recognisably different ecological forest types have been described and mapped. If representative samples of each forest type can be set aside as nature reserves and isolated so far as possible from interferance by man, the great majority of tree species and forest dwelling animals will be conserved.
As argued for individual species more than one sample should be reserved; a central area representing the forest type at its optimum development and 3 or 4 peripheral samples representing specialized variants of the main type. For simple forest communities samples about 1 km2 in extent would probably be large enough: for tropical forests very much larger samples will be needed.
References
DYSON, W.G. | (1968) | Notes on Conservation of Forest Gene Resources. Unpublished paper to FAO Panel of Experts on Forest Gene Resources, Rome 21–25 October 1968, 7pp |
" | (1971) | The Need for Additional Measures to Preserve Forest Types and Particular Tree Species. (Paper for:) East African Specialist Committee for Forestry Research Nairobi, Kenya, October 1971, 6pp |
HARDY, G.H. | (1908) | Mendelian Proportions in a mixed population Science, 28: 49–50 |
STERN, C. | (1954) | The Hardy-Weinberg Law, Science, 97: 137–138 |
Sewall WRIGHT | (1930) | Evolution in Mendelian Populations, Genetics 16: 97–159 |
FISHER, R.A. | (1930) | The Genetical Theory of Natural Selection, Oxford: 272 pp |
WRIGHT, S. & W.E. KERR | (1954) | Experimental Studies of Gene Frequencies in very small populations of Drosophila melanogaster, II Evolution 8: 225–240 |
CAIN, A.J. & P.M. SHEPPARD | (1954) | Natural Selection in Cepaea, Genetics, 39: 89–166 |
BRIGGS, D & S.M. WALTERS | (1969) | Plant Variation and Evolution Wiedenfelt & Nicholson, London: 256 pp |
AGNEW, A.D.Q. | (1968) | Variation and Selection in an Isolated series of Populations of Lysimachia volkensii Engl. Evolution 22: 228–236 |
EDWARDS, M.V. | (1963) | The use of Exotic Trees in Increasing Production with particular preference to N.W. Europe. Paper No. 4/2, Proc. World Consultation on Forest Genetics, Stockholm, 1963, FAO, Rome, 1963 |
Chairman | R. H. Demuth Partner, Surrey, Karasik & Morse 1156 15th Street, N. W. Washington, D.C. 20005 | U. S. A. |
Vice-Chairman | G. de Bakker General Director, Agricultural Research, Ministry of Agriculture and Fisheries, The Hague | Netherlands |
Members | F. Albani Director, Plant Production and Protection Division, FAO, Rome | F. A. O. |
P. Bouvarel Chief, Department of Forestry Research, National Institute of Agronomic Research, Champenoux, Einville | France | |
D.D. Brezhnev Director, N.I. Vavilov All-Union Scientific Research Institute of Plant Industry, Leningrad | U.S.S.R. | |
A. H. Bunting Professor, Department of Agricultural Development Overseas, University of Reading, Reading | U. K. | |
J. L. Creech Director, National Arboretum, Agricultural Research Service, Northeastern Region, U.S. Department of Agriculture, Washington, D.C. | U. S. A. | |
G. Fischbeck Professor, Institut für Pflanzenbau und Pflanzenzüchtung, Technische Universität Munchen, 8050 Freising-Weihenstephan | Fed. Rep. of Germany | |
A.B. Joshi Director, Indian Agricultural Research Institute, New Delhi | India | |
L. Kåhre Director, Swedish State Seed Testing Institute, S-17173 Solna | Sweden | |
W. F. Kugler Professor, Faculty of Agronomy, University of La Plata, Buenos Aires | Argentina | |
B. Majisu Director, East African Agriculture and Forestry Research Organization (EAAFRO), Kikuyu | East African Community | |
Setijati Sastrapradja Director, National Biological Institute, Bogor | Indonesia | |
L. M. Roberts Associate Director, Agricultural Sciences Programme, The Rockefeller Foundation, New York | Rockefeller Foundation | |
V. Taysi Professor, Department of Agroecology and General Plant Breeding, Ege University, Izmir. | Turkey |
Computer-based data banks for international, tropical provenance experiments
by
J. Burley, I.A. Andrew and H.J. Templeman
Commonwealth Forestry Institute,
Oxford University, England
(Reprinted from “Tropical provenance and progeny research and international cooperation” edited by J. Burley and D.G. Nikles, CFI, Oxford, pp. 357–365)
Introduction
The Food and Agriculture Organization of the United Nations (FAO), and the International Union of Forestry Research Organizations (IUFRO) are concerned individually or jointly with research institutes in Australia (Forest Research Institute, Canberra), Denmark (Danish-FAO Seed Centre, Humlebaek), England (Commonwealth Forestry Institute, Oxford), France (Centre Technique Forestier Tropical, Nogent-sur-Marne) and Mexico (Instituto Nacional de Investigaciones Forestales, Mexico City) in the planning and coordination of many international, tropical provenance trials including those shown in table 1 (which have been initiated within the last ten years).
As these experiments mature large quantities of data accumulate on the original seed sources and on the performance or properties of the populations in the planted experiments. Many countries wish to know how given provenances perform in other similar conditions; many individuals wish to know the distribution of a particular provenance throughout the world; still others want to obtain all the information that is available about the site conditions and genetic history of a natural seed source.
It is therefore desirable to set up systems of information storage and retrieval that can provide the required information quickly without repeated and laborious correspondence or file-searching. At the same time the systems should act as permanent archives for data that are of considerable international interest beyond their country of origin. This is particularly important for tropical and developing countries where the research programmes are new, species are little known, seeds of some sources are rare, and staff changes are frequent, yet fast growth rates necessitate early decisions about choice of seed source. In these cases the maximum security and ease of retrieval are sought for all information obtainable.
Burley and Andrew (1972) outlined some of the needs for data processing (from field collection to statistical analysis) in international tree breeding experiments. Here we are concerned with the limited topic of provenance research but the system described below can clearly be applied to other areas of research such as selection and progeny testing, gene conservation plantations, introduction records, etc.
The object of this paper is to present the salient features of the system being developed at the CFI, and to stimulate verbal and written discussion of the types of data that should be considered for storage in an international data bank.
Description of the system
The system is being developed by the staff of the Unit of Tropical Silviculture at the CFI, Oxford on the ICL 1906A computer at the Oxford University Computer Laboratory.
Input
The system is flexible to allow for data to be missing, i.e. failure to obtain some information about a seed source or a site does not cause the whole system to fail. It is flexible also to allow data of varying types to be included, e.g. quantitative, qualitative (categorical) and subjective comments. Information that becomes available later can be added.
All data is coded for easy identification on input or output so that not all measured traits have to be the same in each experiment, e.g. MHT 4.5. 3.1 and MHT 5.0 3.9 could be the mean heights (3.1 and 3.9 m) of a provenance in two different experiments measured 4.5 and 5 years after planting.
The system comprises several computer files each containing different sets of data, each cross-referenced to all others and together forming INTFORPROV, the data banks. The data banks can be interrogated by means of the FIND2 multiple enquiry programme developed by International Computers Limited.
Interrogation
The system is not intended to contain data in a form suitable for statistical analysis (of variance, for example). It is assumed that suitable analyses have been performed where necessary for each individual experiment prior to the inclusion of mean values in the data bank. “International” analyses, such as estimating genotype-environment interaction, will be performed on raw data by the coordinating agencies.
Rather it is intended to provide listings of all or part of the information known about a given provenance, a given site, or combinations of selected provenances and sites. The three most common types of queries are:
What is known about the source of provenance X? A subsidiary enquiry may request only the temperature or other special records for this seed source.
What is known about the places where provenance X was planted? Subsidiary forms may restrict this question to temperature records or to countries with a given latitude or altitude.
How did provenance X perform in field experiments? “Performance” may be restricted to survival, height growth, diameter growth, basal area or volume growth, stem form and crown form, or it may include wood and paper properties, biochemical traits or taxonomic characteristics.
Output
The output summarises the questions asked, tabulates the relevant coded data, and lists the codes; as far as possible IUFRO abbreviations are used but most of the codes are self-explanatory, in English, at least.
Data files
The files proposed at present are described below. Some of these may be found to be unnecessary or others may be needed. The system is open-ended and additions or deletions of files cause no problems.
File 1. Source information for each provenance
1.1 Origin | 1.1.1 | Coding Computer code number; accession number; related seed accession numbers; related herbarium accession numbers; related wood sample numbers; related chemical sample numbers |
1.1.2 | Location Latitude; longitude; altitude; local name | |
1.2 Climate | 1.2.1 | Rainfall Mean, mean minimum, mean maximum, absolute minimum, absolute maximum for 12 months and annual average |
1.2.2 | Temperature - Ditto - | |
1.2.3 | Relative humidity - Ditto - | |
1.2.4 | Number of days with frost | |
1.2.5 | Wind Comment on prevailing direction and speed; comment on hurricane probability | |
1.2.6 | Station Distance to nearest meteorological station, comment on reliability of records | |
1.3 Topography | 1.3.1 | Aspect N, NE, E, SE, S, SW, W, NW |
1.3.2 | Slope Steep, broken, gentle, flat | |
1.4 Soil | 1.4.1 | Parent material Sedimentary, igneous, metamorphic |
1.4.2 | Texture Six classes from fine clays to skeletal gravels | |
1.4.3 | Drainage Five classes from impeded to excessive | |
1.4.4 | Topsoil pH | |
1.5 Vegetation and ecology | ||
1.5.1 | Natural vegetation type Grassland, savannah, woodland, closed forest | |
1.5.2 | Fire Three classes of severity | |
1.5.3 | History Comment on site history | |
1.5.4 | Dryness Subjective comment on dryness | |
1.6 Genetic history | ||
1.6.1 | Forest type Natural forest, plantation, seed stand, seed orchard, clone bank, arboretum | |
1.6.2 | Treatment None, eugenic, dysgenic, random | |
1.6.3 | Method of collection Climbing, felling, shooting, shaking, fallen seed, animal caches | |
1.6.4 | Method of extraction Comment whether sun or machinery | |
1.6.5 | Selection Number of trees, average age, average diameter, average height, average bark thickness, average diameter, growth over last five years | |
1.6.6 | Stand quality Subjective assessment of three classes of stem and crown form | |
1.6.7 | Neighbours Distance from nearest similar population | |
1.6.8 | Disease Comment on insect and disease status | |
1.7 Seed collected | Date, weight, collector | |
1.8 Seed storage | Location, germination percentage, number of seeds per kilogram, date of test | |
1.9 Conservation | Comment on activities or needs | |
1.10 References | Authors, date and journal of publications referring to the seed source | |
1.11 Other |
File 2. Distribution of provenances to sites in international trials
A two-way table prepared by the coordinators of international trials and cross-filed with all other files to give details of source, planting site and performance.
File 3. Site information for each field experiment
3.1 Location | 3.1.1 | Coding International code number, local code number |
3.1.2 | Place Country, place name, latitude, longitude, altitude | |
3.2 Climate | 3.2.1 | Rainfall Mean, mean minimum, mean maximum, absolute minimum, absolute maximum for 12 months and annual average |
3.2.2 | Temperature - Ditto - | |
3.2.3 | Relative humidity - Ditto - | |
3.2.4 | Number of days with frost | |
3.2.5 | Wind Comment on prevailing direction and speed; comment on hurricane probability | |
3.2.6 | Station Distance to nearest meteorological station, comment on reliability of records | |
3.3 Topography | 3.3.1 | Aspect N, NE, E, SE, S, SW, W, NW |
3.3.2 | Slope Steep, broken, gentle, flat | |
3.4 Soil | 3.4.1 | Parent material Sedimentary, igneous, metamorphic |
3.4.2 | Texture Six classes from fine clays to skeletal gravels | |
3.4.3 | Drainage Five classes from impeded to excessive | |
3.4.4 | Topsoil pH | |
3.4.5 | Effective rooting depth | |
3.5 Vegetation, ecology, site history | ||
3.5.1 | Original vegetation type Grassland, savannah, woodland, closed forest | |
3.5.2 | Land use history Virgin forest, agriculture, forest plantation, mining | |
3.5.3 | Ground preparation Taungya, clearing, burning, ploughing | |
3.5.4 | Type of plants used Bare root, potted, direct sown | |
3.5.5 | Planting espacement | |
3.6 References | Authors, date, and journal of publications referring to the site | |
3.7 Responsibility | Address of office responsible for field experiment | |
3.8 Other |
File 4. Nursery and field performance for each experiment
(All data should represent provenance means and standard errors, not plot means nor individual tree values. These should be expressed as mean variances within a provenance as a provenance characteristic)
4.1 Location | 4.1.1 | Coding International code number, local code number |
4.1.2 | Place Country, place name, latitude, longitude, altitude | |
4.2 Design | 4.2.1 | Nursery Number of replications, number of trees per plot. Fully random, randomised blocks, latin square, lattice, other |
4.2.2 | Field - Ditto - | |
4.3 Provenance | 4.3.1 | Supplier's accession number |
4.3.2 | Local code number | |
4.4 Dates | Sowing, pricking-out, planting, field assessments | |
4.5 Seed and seedling traits Germination %, cotyledon number, length, hypocotyl length | ||
4.6 Survival | In nursery and field. (Time coded by months in nursery, and years from planting in field, including decimal parts) | |
4.7 Height | 4.6.1 | Mean of all trees with standard error (Time coded); number assessed |
4.6.2 | Mean of 100/ha with largest diameter (dominant height) with standard error (Time coded); number assessed | |
4.8 Diameter | 4.7.1 | Mean and standard error (Time coded); number assessed |
4.9 Basal area or volume per hectare Mean and standard error (Time coded) | ||
4.10 Stem form | 4.9.1 | Number of basal shoots |
4.9.2 | Number of forks | |
4.9.3 | Number of stem bends | |
4.9.4 | Greatest deviation from vertical | |
4.9.5 | Bark thickness | |
4.9.6 | Taper measurements | |
4.11 Crown form | 4.10.1 | Number of whorls per unit length |
4.10.2 | Number of branches per whorl | |
4.10.3 | Branch length | |
4.10.4 | Branch diameter | |
4.10.5 | Branch angle | |
4.12 Other traits | 4.11.1 | Amount and season of flowering |
4.11.2 | Phenology of flowering | |
4.11.3 | Phenology of growth |
File 5. Wood properties and suitability for forest industries
5.1 Location | 5.1.1 | Coding International code number, local code number | |||
5.1.2 | Place Country, place name, latitude, longitude, altitude | ||||
5.2 Provenance | 5.2.1 | Supplier's accession number | |||
5.2.2 | Local code number | ||||
5.3 Dates | Planting, sampling | ||||
5.4 Physical properties (Mean, standard error, number of samples, trees, replications) | |||||
5.4.1 | Tracheid dimensions | ||||
5.4.1.1 | Length | ||||
5.4.1.2 | Width (radial, tangential) | ||||
5.4.1.3 | Lumen diameter (radial, tangential) | ||||
5.4.1.4 | Cell wall thickness (radial, tangential) | ||||
5.4.2 | Density | ||||
5.4.3 | Grain angle | ||||
5.4.4 | Shrinkage - green to 12% moisture content | ||||
5.4.4.1 | Radial | ||||
5.4.4.2 | Tangential | ||||
5.4.4.3 | Longitudinal | ||||
5.4.4.4 | Volumetric | ||||
5.5 Strength properties (Mean, standard error, number of samples, trees, replications) | |||||
5.5.1 | Bending | ||||
5.5.1.1 | Modulus rupture | ||||
5.5.1.2 | Modulus of elasticity | ||||
5.5.1.3 | Total work | ||||
5.5.2 | Axial compression | ||||
5.5.3 | Hardness | ||||
5.5.4 | Shear | ||||
5.5.5 | Cleavage | ||||
5.5.6 | Tension | ||||
5.6 Durability (with comment on sampling) | |||||
Scaled very durable, durable, moderately durable, non-durable | |||||
5.7 Preservation properties (with comment on sampling) | |||||
5.7.1 | Vacuum pressure impregnation. Scaled very resistant, resistant, moderately resistant, permeable (for heartwood and sapwood) | ||||
5.7.2 | Hot and cold dipping. Scaled as above | ||||
5.7.3 | Dip diffusion. Scaled as above | ||||
5.7.4 | Paint retention | ||||
5.8 Seasoning distortion (with comment on sampling) | |||||
5.8.1 | Bow. Scaled nil, mild, moderate, severe | ||||
5.8.2 | Spring | ditto | |||
5.8.3 | Twist | ditto | |||
5.8.4 | Crack | ditto | |||
5.8.5 | Collapse | ditto | |||
5.9 Sawn timber production (with comment on sampling) | |||||
5.9.1 | Structural | Scaled suitable, marginal, unsuitable | |||
5.9.2 | Joinery | ditto | |||
5.9.3 | Furniture | ditto | |||
5.9.4 | Shuttering | ditto | |||
5.9.5 | Shingles | ditto | |||
5.9.6 | Weather boarding | ditto | |||
5.10 Plywood and veneer production (with comment on sampling) | |||||
5.10.1 | Decorative veneers | Scaled suitable, marginal, unsuitable | |||
5.10.2 | Standard face veneers | ditto | |||
5.10.3 | Cores | ditto | |||
5.10.4 | Gluing | Scaled good, medium, poor | |||
5.11 Pulp and paper (with comment on sampling) | |||||
5.11.1 | Kraft process | ||||
5.11.1.1 | Tear strength | ||||
5.11.1.2 | Burst strength | ||||
5.11.1.3 | Breaking length | ||||
5.11.1.4 | Yield | ||||
5.11.1.5 | Freeness | ||||
5.11.2 | Sulphite process | ||||
5.11.2.1 | Tear strength | ||||
5.11.2.2 | Burst strength | ||||
5.11.2.3 | Breaking length | ||||
5.11.2.4 | Yield | ||||
5.11.2.5 | Freeness | ||||
5.11.3 | Soda process | ||||
5.11.3.1 | Tear strength | ||||
5.11.3.2 | Burst strength | ||||
5.11.3.3 | Breaking length | ||||
5.11.3.4 | Yield | ||||
5.11.3.5 | Freeness | ||||
5.11.4 | Semichemical process | ||||
5.11.4.1 | Tear strength | ||||
5.11.4.2 | Burst strength | ||||
5.11.4.3 | Breaking length | ||||
5.11.4.4 | Yield | ||||
5.11.4.5 | Freeness | ||||
5.11.5 | Groundwood process | ||||
5.11.5.1 | Tear strength | ||||
5.11.5.2 | Burst strength | ||||
5.11.5.3 | Breaking length | ||||
5.11.5.4 | Yield | ||||
5.11.5.5 | Freeness |
Table 1. Major, international, tropical, provenance trials
Species | Coordinators | Number of provenances | Number of countries, institutes or sites receiving seed of some or all provenances |
Araucaria angustifolia | FAO, Rome | 23 | 7 |
Cedrela odorata | CFI, Oxford | 14 | 18 |
Eucalyptus camaldulensis | CTFT, Nogent | 49 | 18 |
E. deglupta | FRI, Canberra | ||
Pinus caribaea | CFI | 31 | 90 |
P. kesiya | FRI/CFI | 21 | 30 |
P. kesiya | Thai/Danish Centre | ||
P. merkusii | CFI | 11 | 21 |
P. merkusii | FRI | 29 | |
P. oocarpa | CFI | 25 | 60 |
P. patula | INIF, Mexico | 18* | |
Tectona grandis | Thai-Danish Centre | 64 | 40 |