Genetic Variability Assessment of Sorghum (Sorghum bicolor (L.) Moench) Germplasm Accessions using Qualitative Morphological Descriptors

Sorghum (Sorghum bicolor (L.) Moench) is considered as the fifth most important cereal crop in the world. It is well adapted to a range of environmental conditions. This study was based on twenty six sorghum germplasm accessions conserved at the seed gene bank of Plant Genetic Resource Center, Gannoruwa, Sri Lanka. The evaluation of the morphological diversity was based on 14 qualitative morphological traits outlined by the International Plant Genetic Resources Institute. Qualitative data recorded from morphological traits were analyzed using PROC CLUSTER procedure of SAS software. The clustering pattern of studied sorghum accessions based on qualitative morphological markers comprised of seven major clusters. Clustering pattern based on the qualitative traits depicts the geographical origin of the studied accessions. This can be explained by the fact that qualitative traits are less influenced by the environment. In principle, qualitative data are expected to provide additional information on hierarchical units. Observation of a considerably high number of clusters consolidates that principle. There were 13 polymorphic qualitative morphological traits with respect to all the studied sorghum germplasm accessions. Cluster I, II, III, IV, V and VI had one or several features shared by all the member accessions those cannot be found in all the members of any other clusters. Also there were unique features restricted to cluster II, III, V and VI. This study reveals sufficient genetic relatedness of studied sorghum germplasm accessions which will meaningful in the conservation and breeding programs of the crops