Nuclear DNA content of Pongamia pinnata L. and genome size stability of in vitro-regenerated plantlets.

Pongamia pinnata L. is a multipurpose versatile legumethatiswellknownasaprospectivefeedstockbiodiesel species. However, to date, there has been little genomic re- search aimed at the exploitation of the biotechnological po- tentialofthisspecies.Geneticcharacterizationofanyplantisa challenging task when there is no information about the ge- nome size and organization of the species. Therefore, the genome size of P. pinnata was estimated by flow cytometry with respect to two standards (Zea mays and Pisum sativum), and compared with that of in vitro-raised plants (nodal seg- ment, invitro-rootedplantletsand acclimatized invitroplants) to study the potential effect of somaclonal variation on ge- nome size. This method can be used to support the establish- ment of true-to-type plants to encourage afforestation pro- grams. Modified propidium iodide/hypotonic citrate buffer was used for isolation of the intact nuclei. The 2C DNAvalue of this species was estimated to be 2.51±0.01 pg. Statistically, there was no significant difference in the DNA content of the in vitro-grown plants and mother plant at α=0.05. As a result of the low genome size of P. pinnata, a species that has adapted itself to a wide range of edaphic and ecological condition, we can now proceed for its next generation se- quencing and genomic diversity studies.