ISSR marker based genetic diversity in Morinda spp. for its enhanced collection, conservation and utilization

Morinda (Rubiaceae) is considerably recognized for its multiple uses viz . food, medicine, dyes, firewood, tools, oil, bio-sorbent etc. The molecular characterization of such an important plant would be very useful for its multifarious enhanced utilization. In the present study, 31 Morinda genotypes belonging to two different species Morinda citrifolia L. and Morinda tomentosa B. Heyne exRoth collected from different regions of India were investigated using inter simple sequence repeat (ISSR) markers. Fifteen ISSR primers generated 176 bands with an average of 11.7 bands per primer, of which (90.34%) were polymorphic. The percentage of polymorphic bands, mean Nei’s gene diversity and mean Shannon’s information index in M. tomentosa and M. citrifolia was [(69.89%, 30.68%); (0.21 ± 0.19, 0.12 ± 0.20) and (0.32 ± 0.27 0.17 ± 0.28)] respectively, revealing higher polymorphism and genetic diversity in M. tomentosa compared to M. citrifolia . These diversity rich genotypes of M. tomentosa can be evaluated for nutraceutical, nutritional and other nonfood purposes to identify trait specific genotypes for its enhanced utilization. ISSR markers based Structure, and UPGMA cluster analysis placed the M. tomentosa and M. citrifolia genotypes into well-defined separate clusters. Further, distinct ecotypes within a particular species could also be inferred. Priority regions identified can be earmarked for exploration and collecting substantial number of genotypes for ex-situ conservation. In-situ conservation of Morinda genotypes in hotspots to preserve the diversity in their natural habitats vis-à-vis evolution and increased adaptation of newer diversity with respect to changing environment was also emphasized.