Population Bottleneck

Population bottleneck refers to a dramatic reduction in genetic diversity within a cannabis breeding line, typically caused by selective breeding from a very small number of parent plants over consecutive generations. This phenomenon is common in early stabilization efforts or when breeders isolate specific traits by repeatedly crossing a limited founder set. While bottlenecks can fix desired characteristics, they also concentrate recessive mutations and reduce overall genetic resilience. Breeders working in this category often document bottleneck events to understand how traits became fixed or how hidden genetic variation may resurface in future crosses. Understanding bottleneck history is essential for outcrossing strategies and predicting phenotypic stability in progeny.

Breeders use bottleneck mapping to trace trait fixation, identify inbreeding depression risk, and plan strategic outcrosses to recover lost allelic diversity. Recognizing bottleneck events in a line's pedigree helps breeders predict segregation patterns and decide when to introduce fresh genetics.