Among the most likely genetic shortcomings of landrace varieties is a lack of genetic uniformity and variety purity. An analysis of genetic heterogeneity was performed on 40 maize landrace seed samples collected from the Lake Zone regions of Tanzania using the Grow Out Test (GOT) method in Randomized Complete Block Design (RCBD). Seed samples were replicated four times, which resulted in 160 experimental units at the SUA experimental area during the 2021/22 cropping season. The assessment of morphological differences within samples was done using International Union for the Protection of New Varieties of Plants (UPOV) guidelines. Genetic heterogeneity analysis results revealed that the majority of the collected samples had two to four genotypes per sample based on the different morphological markers used. These results showed up to 25% level of genetic heterogeneity and varied significantly within and across the collected landrace seeds for some samples. Knowledge and awareness on improving the genetic purity of landrace seeds may need to be harnessed among the respective farmers so as to improve genetic purity through selection and using proper methods of seed production. Genetic purity analysis using molecular markers is recommended for further studies, breeding, and conservation purposes.

Keywords: Genotypes, morphological markers, genetic purity, farm-saved seeds.