Contents - Index

Independent Culling


Independent Culling is a selection strategy whereby a genotype is culled if it does not meet the requirement for a single trait, regardless of its levels on other traits. This strategy guarantees that a genotype that is selected as a new cultivar/variety has no major defects.


In the multi-trait selection tool of GGEbiplot, Independent culling on a trait is conducted by considering three pieces of specifications by the researcher:


1. Culling rate (0 to 50%),


2. Weight (relative importance, [-1, +1]) of the trait, and


3. Action direction of the trait (the sign of the weight).


For Example: If the culling rate is 30%, and the weight of the trait is 0.5, then genotypes with a value of 0.15 (=  0.3 * 0.5) or lower relatitve to the maximum value of the trait will be discarded. If the culling rate is 30%, and the weight is -0.6, then genotypes of a value of 0.82 (= 1 - 0.3 * 0.6) or higher relative to the maximum will be discarded.