Phenotype testing

1. Comparison of long-term breeding strategies using phenotype, clonal, progeny testing for Eucalyptus Darius Danusevičius1,2 and Dag Lindgren11- Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, S-901 83, Umeå, Sweden.2- Lithuanian Forest Research Institute, Girionys, LT-4312, Kaunas reg., Lithuania.

2. Objective: comparing long term cycling strategies based on phenotype, clone or progeny testing by considering gain, diversity,costand time Clone or progeny testing Phenotype testing N=50 N=50 (…n) (…n) (…n) (…n) (…m) (…m) (…m) (…m) (…m) (…m) (…n), (…m) and selection age were optimized under a budget constraint

3. Long-term benefit 2. Gain per time (engine) 3. Diversity potential Other things, e.g. to well see the road 1. Depth of the pocket

4. Long-term breeding benefit C large breeding pop Diversity Gain small breeding pop Group Merit per time = (GAIN – C * DIVERSITY LOSS) / TIME

5. The long-term program Mating Within family selection Recurrent cycles of mating, testing and balanced selection NS=50 Testing

6. Cycle time and cost Cycle cost • Recombination cost • Cost per tested genotype (CL & PR) • Cost per test plant (= 1’$’) Under a budget constraint Cycle time • Recombination time • Time for production of test plants • Testing time Time is money

7. Scenarios Low Main High Genetic parameters Time components Cost components lower reasonable bound assumed typical for Ecalyptus higher reasonable bound While testing an alternative parameter value, the other parameters were at main scenario values

8. And then we did the thing … Parameters Results Breeding cycler at www.genfys.slu.se/staff/dagl.

9. Results Progeny Phenotype Clone Phenotype ~ Clone; Phenotype ~ Progeny GMG/Y, % If resemblance between genotype and phenotype is high, there is less need to test it. For all tested scenarios, clone strategy was superior

10. Progeny Phenotype Clone GMG/Y, % Short rotation (=high J-M correlation at normal rotation), favored PH as it is cheap and the budget constraint allows fast testing (= higher gain per time).

11. Dominance variance had a minor effect and was less favourable for Clone strategy. • Diversity loss had a minor effect (~ 25 or 80 individuals).BP can be sublined according to BV of the members. For PH, cycles are shorter = faster loss of diversity; and if BP is small, PH ~ PR.

12. Progeny Phenotype Clone GMG/Y, % Effect of genotype cost was small. Increasing the genotype cost is an option only if other benefits can be achieved. Cost per test plant was important, but less important for phenotype strategy.

13. Progeny Phenotype Clone GMG/Y, % At short Tbefore, PR ~ PH, thus, for PR the first flowering could be speeded up and at a high cost as increase of genotype-dependent cost was not so important. Phenotype strategy is better the lower the budget is, but at high budget it is not superior to Progeny strategy

14. Conclusions • Clonal testing is suggested to be the best testingstrategy. • Phenotype testingis most to its advantage at high h2.If clone testing is not an option, it seems preferable to progeny testing at short rotations and low budget. • Progeny testingcan be better than phenotype testingwhen h2 is very low, flowering early, budget high and rotation long.

15. 3.Check the final result Breeding Cycle Analyser If your breeding plan is based on cycling and within family selection, then which is the best testing strategy for selection of the new parents? Find the answer by the aid of this simulator which allows you to consider gain, diversity, cost and time simultaneously. It is easy to use and is just a few mouse clicks away from you at www.genfys.slu.se/staff/dagl 1.Set the parameters common for all the testing alternatives 2. Set specific parameters for each testing alternative and find optimum test size and time