Morpho-molecular diversity assessment of Indian kino (Pterocarpus marsupium Roxb.)

Abstract

Tropical dry deciduous forests of central India harbours numerous socio-economically important tree species seriously threatened by biotic and abiotic factors. In this study, we assessed the mopho-molecular variation in Pterocarpus marsupium, a medicinally important tree species. Analysis of morphological data revealed that in P. marsupium, tree height ranged from 5.0 m to 48 m, clear bole height from 2.0 m to 26.0 m and girth at breast height from 45.0 cm to 345.0 cm. It is also evident that all the investigated morpho-metric traits have large amount of variation. The high estimates of coefficient of variation were recorded for crown radius (58%) followed by girth at breast height (54%) and tree height (34%). Molecular diversity analysis using 20 inter simple sequence repeat markers detected 76.7% polymorphism indicating existence of moderately high amount of variability. The average values of genetic diversity indices were 1.67 for mean observed number of alleles (Na), 1.57 for effective number of alleles (Ne), 0.46 for Shannon's information index (I), and 0.32 for expected heterozygosity (He). Bayesian model-based STRUCTURE analysis revealed existence of two admixed genetic clusters of P. marsupium. Further, analysis of molecular variance suggests that most of the variation exists within (91%), rather than among clusters. Sara, Semariya, Lamta and Bahoriband populations were found to be appropriate candidates for initiating conservation measures. The overall results could be a valuable input for formulating effective and integrated in-situ and ex-situ conservation plan for this valuable forestry species.