Evaluation of genetic fidelity of in vitro-propagated Aloe vera plants using DNA-based markers

Abstract

Aloe vera is a world-recognized medicinal herb cultivated for its high value in medicine and the cosmetics industry. Natural multiplication of this plant through suckers is inadequate to meet the demand of high quality planting material for commercial cultivation. Earlier we developed an efficient micropropagation protocol using shoot tip explants of field grown seedlings. Field trials of the micropropagated plants reveal no morphological or growth abnormalities. For commercial utility it is therefore imperative to establish genetic uniformity of micropropagated plants to confirm the true-to-type plantlets. Hence the present investigation assesses the clonal fidelity of the in vitro A. vera plants using polymerase chain reaction-based techniques such as random amplified polymorphic DNA (RAPD) and inter simple sequence repeat (ISSR). In this study, we assessed the suitability of 20 RAPD and 12 ISSR primers to observe any polymorphism. Out of these, 12 RAPD and 8 ISSR primers produced resolvable, reproducible and scorable bands. The 12 RAPD primers produced 75 distinct and scorable bands with an average of 6.25 bands, and 8 ISSR primers produced 31 distinct and scorable bands with an average of 3.8 bands per primer. RAPD and ISSR profiles obtained through the amplification of genomic DNA of the in vitro grown A. vera plants were similar in all aspects. No RAPD and ISSR polymorphism in the micropropagated plants were detected. This implies that micropropagation through shoot tip explants is a safe method for producing true-to-type plants and could be used for commercial plantation of A. vera.