Analysis of diversity amongst widely distributed and endemic Atalantia (family Rutaceae) species from Western Ghats of India.

The genus Atalantia Correa is represented in India with four species and two varieties. The infra - generic classification and the species limits in Atalantia are, however, not well defined, due to the occurrence of intermediate forms. Two species, A. racemosa Wight and A. monophylla (L.) DC., are widely distributed, while the third species, A. wightii Tanaka is endemic in the Western Ghats, a well-known biodiversity hotspot. PCR-based methods have been commonly used for the assessment of genetic diversity in plants. We report for the first time the genetic diversity within and between populations of the above three species using two Single Primer Amplification Reaction (SPAR) methods. AMOVA analysis clearly indicates the lesser diversity among the species than within them. The UPGMA tree included all of the doubtful species in one single sub-cluster within the major cluster of A. racemosa and A. wightii, suggesting that these are probably hybrids derived from these two species. At the population level, all A. monophylla populations grouped together in a cluster that was clearly separated from all other species and populations.