Modulated gene expression in newly synthesized auto-tetraploid of Papaver somniferum L.

Abstract

Autopolyploidy is advantageous for plant metabolism in terms of elevated rates of synthesis or a higher variability of metabolically relevant compounds. In the present study, successful induction of polyploidy was achieved through applying colchicine soaked cotton on shoot meristem. The ploidy level of the developed tetraploids was confirmed through microscopic observations of stomata and chromosomal studies. Chromosome number in the developed tetraploids were 2x = 2n = 44 as compared to the control having 2x = 2n = 22. Alkaloid profile of both treated and control plants showed a significant enhancement from 25% to 50% in morphine content. Expression analysis through semiquantitative reverse transcription-polymerase chain reaction (RT-PCR) of various known genes involved in the biosynthesis of morphinanes showed increased expression in tetraploids. Gene expression analysis of different polyploidy series can supplement our understanding related to molecular mechanism involved in increased alkaloid biosynthesis during polyploidization.