Assessment of the morphological and molecular diversity in Amaranthus spp.

Genetic diversity and relationships of 15 Amaranthus species were examined by using both morphological traits and random amplification of polymorphic DNA (RAPD) markers. Ten morphological observations were recorded out of which seven were subjected to analysis of variance. Mean squares due to genotypes were highly significant. Wide mean range performance was observed for number of effective tillers per plant (9 to 12.3), spike length (16.7 to 42.4 cm), spike mass (16.2 to 24.5 g), seed yield per plant (6.4 to 16.6 g), biological yield per plant (19.8 to 28.6 g), harvest index (32.9 to 57.1%) and seed protein content (15.75 to 16.49). RAPD analysis has been carried out using 12 arbitrary sequence decamer primers. Seventy four amplicons were obtained out of which 58 were polymorphic and the level of polymorphism was 78.3%. The average number of polymorphic bands per primer was 4.8. From the RAPD data, an unweighted pair-group method arithmetic (UPGMA) dendrogram illustrating the genetic relationship among fifteen genotypes were computed. The trends of genotypes relationship amongst the Amaranths spp. determined by RAPDs are consistent with their morphological traits.   Key words: Amaranthus, random amplification of polymorphic DNA (RAPD), genetic relationship, polymorphism.