Tree Improvement 101 - Module 2: Modes of Selection in Tree Improvement Programs
Webinar Details
When:
Apr 12, 2024 1:00 pm US/Eastern
Length: 01:00 (hh:mm)
Advance Registration NOT required.
View now on-demand.
Presenter(s):
- Charles Dana Nelson PhD - Research Geneticist / Project Leader, Southern Research Station, Southern Institute of Forest Genetics, Harrison Experimental Forest, US Forest Service
- Carolyn "Carrie" Pike PhD - Regeneration Specialist, Reforestation, Nurseries, and Genetic Resources (RNGR) Program, USDA Forest Service - Eastern Region State, Private, and Tribal Forestry
Virtual Event Format:
Group Viewing Available:
Module 2: This module will dig deeper into selection, including forward vs backwards selection.
We will look different types of genetic effects with a deep dive into additive genetic variation. We will also explore how heritability is calculated and interpreted for breeding programs.
Additional Information
Tree improvement programs are systematic efforts to improve the genetic quality of trees for specific traits. These traits can include growth rate, wood quality, disease resistance, and adaptability to environmental conditions. The modes of selection in tree improvement programs refer to the methods used to choose the best individuals or populations for breeding.
Here’s a more detailed explanation of the modes of selection:
1. Additive Genetic Variation: This is the sum of individual genetic effects across loci, and it’s the primary source of variation that tree improvement programs aim to exploit. Trees with favorable additive genetic variation are selected for breeding to pass these desirable traits to the next generation.
2. Heritability Calculation: Heritability is a measure of how much of the variation in a trait is due to genetic factors. In tree improvement programs, high heritability indicates that a large portion of the variation in a trait (like growth rate) is due to genetic differences, making it a good candidate for selection.
3. Candidate Plus Tree Selection (CPTs): Plus trees are those that exhibit superior traits compared to their peers. These trees are selected as candidates for breeding. The selection is based on various factors such as growth rate, tree form, resistance or tolerance to a pest, and adaptability to site conditions.
4. Progeny Selection (forward vs backward selection): This involves growing and assessing the offspring (progeny) of selected parents. The best performing progeny are then chosen for further breeding. This method allows for the evaluation of both the genetic quality of the parents and the additive genetic value of the progeny. In contrast, with backwards selection the progeny are studied to rate the parental values.
These modes of selection are used in combination to achieve the goals of the tree improvement program. The ultimate aim is to enhance the genetic value of the tree population, leading to improved productivity and sustainability of forests. It’s important to note that the success of these programs relies heavily on long-term commitment, as genetic improvements in trees are realized over several decades.
About Our Presenter(s)
https://rngr.net
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