Analysis of genetic diversity among Tagetes patula L. cultivars based on RAPD markers

Abstract

Twelve cultivars of Tagetes patula with distinct floral characteristics were analysed through RAPD profiles. Twenty two polymorphic primers produced a total of 233 bands out of which 188 bands were polymorphic with an average of 8.1 polymorphic bands per primer. The size of the amplified fragments ranged from 200-6000 bp. The percentage of polymorphic bands ranged from 50 (OPF-01 and OPT-20) to 100% (OPF-04, OPF-14, OPF-15, OPT-17) with an average of 75.8% polymorphism. The Polymorphic Information Content (PIC) values ranged from 0.19 (OPT-20) to 0.44 (OPA-10, OPT-12). A relatively higher genetic variability was detected among the cultivars and had similarity coefficient values ranging from 0.42 to 0.93. Cluster analysis based on Jaccard’s similarity coefficient using Unweighted Pair Group Method with Arithmetic Averages (UPGMA) grouped all the 12 cultivars into three major groups at a similarity coefficient of 0.53. The greatest similarity was found between Boy Mix (BM) and Boy Spry (BS) (Jaccard's coefficient = 0.93), while Boy Gold (BG) was found to be most distinct genotype. A total of 8 primers detected in the study produced unique allele in five genotypes. This results showed that the level of genetic variation was high among the Tagetes cultivars. It also indicated the higher potential of RAPD markers for identification and maintenance of Tagetes germplasm for crop improvement purposes.