male reproductive investment and success in a larix occidentalis seed orchard population tomas funda...

Male reproductive investment and success in a Larix occidentalis seed orchard population

Tomas FundaFaculty of Forestry, University of British Columbia, Canada

tfunda@interchange.ubc.ca

Outline• Introduction– Seed orchards– Fertility variation

• Materials and Methods– Western larch clonal seed orchard– Microsatellite DNA paternity analysis

• Results– Regression analyses– Genetic gain and diversity estimates

• Summary– Benefits of the simplified methods

Seed orchards Artificial populations of genetically superior trees Mass production of improved seed

http://www.hupptreefarm.com/seed_orchard.htm

Genetic gain Parental breeding values Reproductive success Pollen contamination

Number of parents Reproductive success Mating pattern Co-ancestry Inbreeding

Genetic diversity

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Reproductive investment vs. success

Investment Female• Number/volume/weight of seed cones• Number of seed per cone• Proportion of filled seed

Male• Number/volume of pollen buds/cones

Reproductive investment vs. success

???

Investment Success

unknown

Reproductive investment vs. success

???

Investment Success

unknown

Reproductive investment methods

M0: Male reproductive success is assumed to be equal to parental representation (i.e., number of ramets per plus tree)

Example: two parents in a seed orchard parent #1: 9 ramets parent #2: 1 ramets then parent #1 assumed to produce 90% of successful male gametes in seed crop whereas parent #2 only 10%

or

Reproductive investment methods

M0: Parental representation

M1: Male reproductive success is assumed to be proportional to crown volume or age of a particular parent

Reproductive investment methods

M0: Parental representation

M1: Crown volume or age adjustment

M2: Visual assessment of pollen production on at least 50% of ramets (partial pollen survey)

M3: Visual assessment of pollen production on every ramet (full pollen survey)

Seed orchard

Species: western larch, 1st generationLocation: Vernon, British Columbia, Canada

(50°14’N, 119°16’E, 480 m a.s.l.)Established: 1989Population size: 41 parents (as of 2005)

Plant material Parental population young foliage from 41 parents

Plant material Parental population young foliage from 41 parents

Offspring population37 half-sib families

• dormant vegetative buds from 2-year-old seedlings• 3-cm-long embryos

Reproductive success

10 nuclear microsatellite DNA markers multilocus probability of exclusion ≅ 1

Reproductive success

10 nuclear microsatellite DNA markers

Paternity assignment using CERVUS 3.0.3Maternal parentage knownUnassigned offspring – contamination

– insufficiently informative genotypes

Reproductive success

10 nuclear microsatellite DNA markers

Paternity assignment using CERVUS 3.0.3

Linear regression using SAS 9.1.3Dependent variable – DNA-based male reproductive success (baseline)Independent variables – fecundity scores for each simplified method(M0, M1, M2, or M3)

Reproductive success

10 nuclear microsatellite DNA markers

Paternity assignment using CERVUS 3.0.3

Linear regression using SAS 9.1.3Dependent variable – DNA based male reproductive success

(baseline)Independent variables – fecundity scores for each simplified method(M0, M1, M2, or M3)

Evaluation based on R2, RMSE, and 95% prediction intervals

Reproductive success

10 nuclear microsatellite DNA markers

Paternity assignment using CERVUS 3.0.3

Linear regression using SAS 9.1.3Dependent variable – DNA based male reproductive success

(baseline)Independent variables – fecundity scores for each simplified method(M0, M1, M2, or M3)

Evaluation based on R2, RMSE, and 95% prediction intervals

Impact on genetic gain and diversityError? Bias?

Does parental representation reflect actual male reproductive success?

Questions

Is male reproductive investment assessed through a field survey a good indication of actual male reproductive success?

Does this assessment provide unbiased estimates of crops’ genetic parameters, such as gain and diversity?

Questions

Genetic diversity status effective number (Ne)

– fertility variation– co-ancestry

Does parental representation reflect actual male reproductive success?

Is male reproductive investment assessed through a field survey a good indication of actual male reproductive success?

Does this assessment provide unbiased estimates of crops’ genetic parameters, such as gain and diversity?

Pedigree reconstruction

Total number of analyzed offspring: 2088

Assigned to one of the 41 candidate fathers: 1848 (88.5%) maximum pollen contamination 11.5%

Selfing 7.6%

Methods’ evaluationM0: Male reproductive success is a function of parental representation

R2 RMSE

M0 0.275 0.072

M1 0.499 0.060

M2 0.702 0.046

M3 0.731 0.0440.001 0.01 0.1

0.00

0.25

0.50

Male reproductive investment (M0)

Mal

e re

prod

uctiv

e su

cces

s (D

NA)

Methods’ evaluationM1: Male reproductive success is a function of parental representation adjusted for crown volume

0.001 0.01 0.10.00

0.25

0.50

Male reproductive investment (M1)

Mal

e re

prod

uctiv

e su

cces

s (D

NA)R2 RMSE

M0 0.275 0.072

M1 0.499 0.060

M2 0.702 0.046

M3 0.731 0.044

Methods’ evaluationM2: Male reproductive success is a function of male fecundity scored on 50% of trees (partial pollen survey)

R2 RMSE

M0 0.275 0.072

M1 0.499 0.060

M2 0.702 0.046

M3 0.731 0.0440.000666666666666665 0.0666666666666665

0.00

0.25

0.50

Male reproductive investment (M2)

Mal

e re

prod

uctiv

e su

cces

s (DN

A)

Methods’ evaluationM3: Male reproductive success is a function of male fecundity scored on all trees (full pollen survey)

R2 RMSE

M0 0.275 0.072

M1 0.499 0.060

M2 0.702 0.046

M3 0.731 0.044

0.00

0.25

0.50

Male reproductive investment (M3)M

ale

rep

rod

ucti

ve s

ucc

ess

(DN

A)

Methods’ evaluationM2: Male reproductive success is a function of male fecundity scored on 50% of trees (partial pollen survey)

R2 RMSE

M0 0.275 0.072

M1 0.499 0.060

M2 0.702 0.046

M3 0.731 0.0440.000666666666666665 0.0666666666666665

0.00

0.25

0.50

Male reproductive investment (M2)

Mal

e re

prod

uctiv

e su

cces

s (DN

A)

correlation = 0.97

Crops’ genetic parameters

M0 M1 M2 M3 DNA0

10

20

30

40

32.830.5

16.4 17.0 18.6

Status effective number

Stat

us e

ffecti

ve n

umbe

r

M0 M1 M2 M3 DNA

M0 M1 M2 M3 DNA10

12

14

16

18

15.915.3

15.9 15.815.3

Genetic worth

Gen

etic

wor

th

M0 M1 M2 M3 DNA

Does parental representation reflect actual male reproductive success?X No, it does not due to substantial male fertility variation.

Questions

Questions

Is male reproductive investment assessed through a field survey a good indication of actual male reproductive success?

Does parental representation reflect actual male reproductive success?

X No, it does not due to substantial male fertility variation.

Yes, it is. ü

Does this assessment provide unbiased estimates of crops’ genetic parameters, such as gain and diversity? Yes, it does, at least in western larch.

Questions

Is male reproductive investment assessed through a field survey a good indication of actual male reproductive success?

Does parental representation reflect actual male reproductive success?

X No, it does not due to substantial male fertility variation.

Yes, it is. ü

ü

“Congruence between parental reproductive investment and success determined by DNA-based pedigree reconstruction in conifer seed orchards”

Canadian Journal of Forest Research (in press)

Acknowledgement

Co-authors:Cherdsak LiewlaksaneeyanawinCharles ChenIrena FundovaChris WalshJack Woods

Supervisor:Yousry A. El-Kassaby

Thank you for your attention

Does this assessment provide unbiased estimates of crops’ genetic parameters, such as gain and diversity? Yes, it does, at least in western larch.

Questions

Is male reproductive investment assessed through a field survey a good indication of actual male reproductive success?

Does parental representation reflect actual male reproductive success?

X No, it does not due to substantial male fertility variation.

Yes, it is. ü

ü