Seed priming with cold plasma improved seedling performance, secondary metabolism, and expression of deacetylvindoline O‐acetyltransferase gene in Catharanthus roseus

The plasma‐primed seeds of Catharanthus roseus were cultured in a hormone‐free culture medium under sterile conditions. Plasma of 30 or 60 s improved root length (mean = 41.4%) and biomass (mean = 47%), whereas plasma of 90 s delayed plant growth. The plasma treatments enhanced concentrations of photosynthetic pigments and soluble phenols. Plasma of 90 s increased the proline level. With a similar trend, plasma priming induced activities of phenylalanine ammonia‐lyase, catalase (about twofold) and peroxidase (31%) enzymes. Plasma also upregulated the expressions of deacetylvindoline O‐acetyltransferase gene by an average of 7.8 times. Similarly, the plasma‐treated seedlings contained higher concentrations of alkaloids (mean = 72%). Here, molecular evidence is provided on the plasma‐associated modifications in secondary metabolism.