Mendelian Ratios

Mendelian ratios describe predictable patterns of trait inheritance across cannabis generations, based on foundational genetic principles established by Gregor Mendel. In cannabis breeding, these ratios help explain how dominant and recessive alleles segregate during reproduction—for example, a 3:1 phenotypic ratio in F2 crosses or 1:1 ratios in testcrosses. Breeders use Mendelian theory to predict terpene expression, cannabinoid profiles, and morphological traits across offspring populations. However, cannabis genetics often deviate from simple Mendelian patterns due to polyploidy, epigenetics, and linkage. Understanding these classical ratios remains a foundational framework for modern cannabis genetics, even when real-world outcomes show complexity.

Breeders reference Mendelian ratios when designing crosses to stabilize desired terpene or cannabinoid traits. Recognizing deviations from expected ratios signals environmental factors, hidden recessives, or non-Mendelian inheritance—critical data for strain selection and line stabilization.