B. Mondal, A. Pal, R. Saha
Abstract: In the present study, Random amplified polymorphic DNA (RAPD) markers were used to study the difference between the zygotic and nucellar embryos of highly polyembryonic Citrus reticulata plant type collected from North Eastern Himalayan (NEH) region. Twenty five decamer oligonucleotide primers were used to amplify genomic DNA extracted from leaf samples. A total of 62 strong, unambiguous amplicons were generated out of which 47 were polymorphic. Hierarchical Cluster analysis based on Squared Euclidean distance using nearest neighbor method of binary data with SPSS software, ver. 16.0 differentiated all the seedlings into two different groups. The seedlings with 100 % similarity were regarded as nucellar or true to the mother type. Other seedlings with slightest difference were regarded as zygotic. Four arbitrary primers OPA18, OPH11, OPB10, OPAA10 were able to discriminate the zygotic and nucellar seedlings. In an open pollinated population with very less morphological distinction, RAPD analysis can rapidly identify the zygotic embryos helps to obtain genetically uniform plant types. This method saves resources and helps in execution of proper management practice to a small uniform population to fix beneficial heterosis for the poor farmers of North Eastern Himalayan region.
Keywords: Citrus reticulata, polyembryony, zygotic, nucellar, RAPD, propagation