Nuclear DNA and Fruit (Seed) Variation in Section Pentaptera of Genus Terminalia Linn.

2C nuclear DNA amounts and fruit (conventionally known as seed) characters were studied in 37 samples collected from 27 mother trees belonging to various taxa of genus Terminalia in section Pentaptera. There were significant differences between various taxa both in nuclear DNA amounts and fruit characters. The divergence and evolution in section Pentaptera was accompanied by very high as well as highly variable nuclear DNA amounts ranging from 8:01 to 9.66 Pg. The element of discontinuity in the distribution of DNA changes between complements was quite regular. The various taxa altogether fell into six cluster groups with an interval of 0.31 Pg. between the two adjoining groups whereas various genotypes of T. glabra and spontaneous hybrids further fell into five and four cluster groups with the interval of 0.3 and 0.55 Pg.respectively. This is probably the second case after Cassia where significant intra-specific nuclear DNA variation has been observed in trees. In the light of hybridization and nuclear DNA studies, there is indeed a case for considering T. glabra, T. berryi, T. coriacea, T. crenulata, T. alata and spontaneous hybrids as separate species and not as the varieties of T. arjuna and T. tomentosa. The nuclear DNA amounts exhibited no correlation with fruit characters of various taxa studied.