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F OREST T REE I MPROVEMENT. DR. AB. RASIP BIN AB. GHANI DIRECTOR FOREST PLANTATION PROGRAMME BIOTECHNOLOGY DIVISION FOREST RESEARCH INSTITUTE MALAYSIA (FRIM) KEPONG, 52109 SELANGOR DARUL EHSAN, MALAYSIA TEL: +603-62797097 FAX: +603-62731427 EMAIL: rasip@frim.gov.my.
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FOREST TREE IMPROVEMENT DR. AB. RASIP BIN AB. GHANI DIRECTOR FOREST PLANTATION PROGRAMME BIOTECHNOLOGY DIVISION FOREST RESEARCH INSTITUTE MALAYSIA (FRIM) KEPONG, 52109 SELANGOR DARUL EHSAN, MALAYSIA TEL: +603-62797097 FAX: +603-62731427 EMAIL: rasip@frim.gov.my
GENERAL CONCEPTS OF TREE IMPROVEMENT • Forest Genetic • Forest tree breeding • Tree Improvement • Step involving in TI • Why we need tree improvement? • Important consideration
Tree Improvement (TI) Forest Genetic – genetic studies of forest trees Forest tree breeding – studies on some specific problem to produce a specially desired product Tree Improvement – combination of all silviculture and tree breeding skill to grow the most valuable forest product as quickly as possible and as inexpensive as possible
Step involving in TI • Species determination – geographic source • Variability studies - amount, kind and causes of • variability • Packaging of desired quality into improved • individual • Mass production of improved individuals • Developing and maintaining a genetic base population broad enough for needs in advanced generation
Why do we need TI? • Intensive tree farming • Production of the desired quality timber in maximum amounts in the shortest period of time at reasonable cost TI:- • Improved yields and quality on the more productive forested area • Can grow tree on land that are sub-marginal and no economic for timber production • Develop strains that are more suitable for specialized products or uses
Important consideration:- Time > Cost > Quality
VARIATION AND ITS USE • Genetic variability • Environmental variation • Variation caused by man • Racial variation • Mating system • Factors shaping variation • Selection
Basis for selection • Especially on the economic traits • Must determine the amount, cause and the nature of variation • The variations in tree species are generally high • Strategy for survival • Long life • Expose to various environmental condition • Giving more opportunity for selection • Basis of variation • At cell level >>>>>> Chromosomes and gene
Causes and kinds of variability Basically the differences among tree resulted from • The differing environments in which the trees are growing • The genetic differences among trees • The interaction between the tree gene types and environment in which they grow P = G + E + GxE G = genetic E= environment GxE = interaction between G&E
Environmental variation Soil >> Light >> H2O >> Space Effect on tree – competition among trees. Factors can be controlled in Silvicultural practices
Genetic Variability Genetic variation = additive gene action + non-additive gene action 2P = 2G + 2E 2G = 2GA + 2GNA 2P = 2GA + 2GNA + 2E Additive gene action = cumulative effects of all gene loci influencing trait
Non-additive divided by two • Dominance – interaction of specific affects at a gene locus • Epitasis – interactions among gene loci Most characteristics of economic importance controlled by additive gene action • Additive variance can be used in simple selection. e.g. wood density, bole straightness • non- additive – e.g. growth rate Pest resistance – both additive & non- additive
SOURCE OF PLANTING MATERIAL • Seed source • Strategies of acquiring planting material • Short-term strategy • Long-term strategy
Source of Seed • The importance of source of seed • Success of plantation depends on seed source • Largest, fastest and cheapest gain can be realized through proper species and seed sources • Terminology: • Adapted – how well trees are physiologically suited for high survival, good growth, resistance to P & D and adverse condition • Exotic - tree grown and of its natural range • Provenance, geographic source or geographic race • denote the original geographic areas from which seed or other propagules were obtained • Seed source – or origin
Racial variation • natural population • between individual within population variation – racial variation Clines and ecotypes Cline – a gradient in a measurable characteristic which follows environmental gradients. Variation may/may not base on genetics. Ecotype – a group of plants of similar genotype that occupy a specific ecological niche • Land race • A population of individuals that has become adapted to a specific environment in which it has been planted • Can be the easiest and best way of making quick and large genetic gains
Where races are developed best? • Species with very wide range over environments • Species growing a wide altitudinal range • Species that grown in regions of greatly diverse soils • Where to select? • Safest method is to select local source • Outside source that have been proven better • From center of origin
Steps to select seed source • Make decision about the objective of the plantings and the products desired • Obtain all information possible • Survey the area for any plantation of desired species- develop S.P.A • Determine the variation within the seed source or provenance • Operationally used seed from initial land race or best potential provenance while better source being developed (through breeding activity)
Selection • Mass selection • Family selection • Sib selection • Progeny testing • Within-family selection • Family plus Within-family selection
Selection of Plus tree • Candidate Plus tree • A tree that has been selected for grading because of its desirable phenotypic qualities but has not yet been graded or tested. • Selected, superior or plus tree • A tree has been recommended for production or breeding orchard use following grading. It has superior phenotype for growth, form, wood quality or other desired characteristics and appears to be adaptable. • Elite tree • Plus tree that has been proven to be genetically superior by mean of progeny testing. • Comparison trees • Trees that are located in the same stand and against which the candidate plus tree is graded. • Advance • Generation selection – A tree selected from genetic test of crosses among parents from previous generations.
Selection • 1. Individual tree selection / mass selection • Even – aged stands • Concentrated on stands and plantation that average or better performance • Same site quality to the plantation • Known seed source • Medium – aged stands • Pure species composition • Avoid logged over stand • Large enough for selection and comparison trees • Emphasis on high seed production • Thorough and systematic search • Used comparison tree method
A C B Regression line Volume growth Age of trees • Uneven aged stand • Regression selection system
Selection of plus tree Teak plus tree
2. Family selection the choice of entire families on the basis of their average phenotypic values 3. Sib Selection individuals are chosen on the basis of the performance of their siblings and not on their own performance 4. Progeny testing Selection of parent trees based upon the performance of their progeny
5. Within-family selection Individual are chosen on the basis of their deviation from the family mean, and family values per se are given no weight when selections are made 6, Family plus Within-family selection Two-stage method involve selection on families followed by selection of individuals within families
Strategies in satisfying the need of planting material • Short term strategies • Proven provenances (provenance trial/ GxE interaction) • Acacia mangium : Oriomo river (PNG) • Claudi River (Northern Territories, Aust) • Pinus caribaea : Hondurus • 2. Land Races • A. mangium • Rubber • Oil palm
3. Plus trees • Seed, vegetative materials • 4. Seed Production Areas/Seed Stands • poor phenotypes are rogued from the stand and good trees are left to intermate.
Long Term Strategies 1) Clone establishment From Plus/Elite trees Vegetative propagation Macro - grafting - layering - cutting Clone banks/ Research orchards Clone test
Clonal Forestry • Uniformity • Adaptation • Cost • Wood production • Deployment of GMO’s • Deployment of hybrids and expensive rare seed • The opportunity to gain a better understanding of individual genotype overtimes and oversight
Teak tissue cultures multiplied in test tubes Biotechnology Tissue culture Teak tissue cultured plants ready for field planting Teak plantation established
2) Seed orchard a) Seedling seed orchard Plus trees/elite trees Seed Set up seed orchard Progeny trial Improved seed orchards b) Clonal seed orchard Plus trees/elite trees Vegetative material Set up seed orchard Progeny trial Improved seed orchards
Acacia hybrid • Hybrids • To combine complimentary traits of two parents • To exploit hybrid vigour (heterosis) • Increase the adaptability for afforestation into marginal areas for that species
QUANTITATIVE ASPECTS OF TREE IMPROVEMENT • Experimental design • Genetic values • Heritability • Selection differential and selection intensity • Genetic gain • Method to obtain gain • Mating design
Experimental Design • CRD • RCBD • Incomplete Block Design • Latticed Design • Row and Column Design
Statistical aspect of FTI Genetic value - To get the best set of parent trees for breeding. P = G + E + GxE Progeny trial - Evaluate the parents through the performance of the progenies. - eliminate the E effect by giving the same environment Genetic value is express in term of Combining ability General Combining Ability (GCA) – the average performance of the progeny of individual when it is mated to a number of other individual in the population.
Specific Combining Ability –the average performance of the progeny of a cross between two specific parents that are different from what would be expected on the basis of their general combining ablity alone. e.g:
For parent 2 (male) GCA = mean of parent 2 – test mean = 17 – 13 = +4 parent 2 has general ability (GCA2) for volume of +4 Breeding value of an individual is defined as twice its general combining ability. Breeding value = 2 (GCA) BV parent 2 = 2 (GCA2) = 2 x 4 = 8
SCA – it always refer to specific cross and never to a particular parent by itself. 3 steps in calculating the SCA : e.g Cross between parents 3 and 6 ( a cross value of 12) Calculate the GCA for both parents GCA3= -3; GCA6 = -1 Calculate the anticipated value of the cross (Summation of test mean and the GCA for both parents) Anticipated value = test mean + GCA3 + GCA6 = 13 + (-3) + (-1) = 9
Subtract the value calculated in (2) from observed value of the cross. SCA3x6 = observed value – anticipated value = 12 – 9 = +3 This means that cross 3 x 6 is performing 3 volume unit better than would be expected based on the GCA’s of parents 3 and 6.
Genotype X Environment interaction The relative performance of clones, families, provenance or species differ when they are planted in different environment. Situation 1 Situation 2
Heritability • 1) Broad-sense (H2) • The ratio of all genetic variance to the phenotypic variance • 2) Narrow-sense (h2) • The ratio of additive genetic variance to phenotypic variance
Selection differential The difference between the mean of selected individual and the population mean _ _ S= Xs- X
Genetic gain • G= h2 x S • Or • G= i h2P • i = intensity of selection • h2 = heritability • P = phenotypic standard deviation
Method to obtain gain • Mass selection followed by testing • Phenotypic selection followed by vegetative propagation and testing • Making special crosses
Mating design • Open pollinated mating • Polycross (pollen mix) design • Nested design • Factorial design • Single-pair mating • Diallel
TREE IMPROVEMENT STRATEGY • Objective • Factors for consideration