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Saraca asoca (Roxb) De Wilde is an increasingly endangered and endemic medicinal plant in India. Genetic assessment is one of the important parameters for formulating conservation strategies for endangered species. Randomly amplified polymorphic DNA (RAPD) profiling was employed to assess the genetic diversity of 165 individuals representing five natural populations. There was a relatively low level of genetic diversity in S. asoca at the species level but a relatively high level of genetic differentiation among populations. Limited gene flow due to human impact may be the key factor resulting in the observed genetic structure. These effects may be most pronounced in species that are self-compatible and/or have limited seed dispersal ability. As S. asoca is highly over-exploited, with small isolated populations and high genetic variation among populations, we believe that all the populations should be protected in situ free from human impact. Gene flow is very limited. Ex situ conservation is also of the utmost importance for better genetic conservation and management of S. asoca.

A highly efficient protocol for in vitro regeneration of an indigenous, endangered medicinal plant Celastrus paniculatus was achieved using nodal explants. Murashige and Skoog (MS) basal medium supplemented with 0.5 mg/L 6-benzylaminopurine (BAP) and 0.1 mg/L naphthaleneacetic acid (NAA) showed maximum percentage of shoot multiplication (83.4%) with 8.2 shoots/explants. Maximum rooting of 73.3% with 4.8 roots/shoot was achieved on half-strength MS media supplemented with 0.5 mg/L indole-3-acetic acid (IAA) and the percentage of survival was 91% after acclimatization. Random amplified polymorphic DNA (RAPD) and inter simple sequence repeat (ISSR) marker study confirmed genetic stability for in vitro raised explants by showing 100% monomorphism. High multiplication rate associated with genetic stability ensure the efficacy of the present in vitro clonal propagation protocol of this important medicinal plant species.

Abstract:The present investigation was undertaken to describe the relationships among twelve species of Phyllanthus collected in India by help of molecular markers. In total, 259 marker loci were assessed, out of which 249 were polymorphic revealing 96.13% polymorphism. Nei's similarity index varied from 0.35 to 0.76 for RAPD (Random Amplified Polymorphic DNA) and from 0.31 to 0.76 for ISSR marker systems. Cluster analysis by the unweighted pair group method (UPGMA) of Dice coefficient of similarity generated dendrogram with more or less similar topology for both the analyses that offered a better explanation for diversity and affinities between the species. The phylogenetic tree obtained from both RAPD and ISSR (Inter Simple Sequence Repeat) markers has divided the 12 species into two groups: group I consisting of only one species Phyllanthus angustifolius (Sw.) Sw and group II with the rest of 11 species. Basically, these results were in compliance with notable morphological characterization. The present study revealed high variation among the species of Phyllanthus and will help to identify different Phyllanthus species.

Germplasm identification and characterization is an important link between the conservation and utilization of plant genetic resources. Traditionally, species or cultivars identification has relied on morphological characters like growth habit or floral morphology like flower colour and other characteristics of the plant. Studies were undertaken for identification and determination of genetic variation within the two species of Hibiscus and 16 varieties of Hibiscus rosa-sinensis L. through random amplified polymorphic (RAPD) markers. Primer screening was made by using the DNA of variety "Prolific". Genetic analysis was made by using ten selected decamer primers. A total of 79 distinct DNA fragments ranging from 0.3 to 2.5 kb were amplified by using ten selected random decamer primers. The genetic similarity was evaluated on the basis of presence or absence of bands. The cluster analysis indicated that the 16 varieties and two species formed one cluster. The first major cluster consisted of three varieties and a second major cluster consisted of two species and 13 varieties. The genetic distance was very close within the varieties and also among the species. Thus, these RAPD markers have the potential for identification of species/varieties and characterization of genetic variation within the varieties. This is also helpful in Hibiscus breeding programs and provides a major input into conservation biology.