The influential role of polyamines on the in vitro regeneration of pea (Pisum sativum L.) and genetic fidelity assessment by SCoT and RAPD markers

Key message An enhanced and consistence in vitro regeneration protocol was established for pea, by the application of polyamines along with PGRs, which significantly improved the multiple shooting, shoot elongation, rooting, total chlorophyll and antioxidant profile of regenerated plants, further not hampering their genetic fidelity. A proficient and reliable in vitro plant regeneration protocol was established for pea by utilizing cotyledonary node as an explants, which excised from 3-days old imbibed seeds. The present research work explains the positive role of polyamines (PAs) accompanied by plant growth regulators (PGRs) on the multiple shoot induction and rooting in pea plant regeneration. The highest multiple shoots (65.1 shoots/explant) was attained from the cotyledonary node explant on Murashige and Skoog (MS) medium accompanied with 20 mg l(-1) spermidine (SPD) along with 1.5 mg l(-1) 6-benzyladenine (BA). Moreover, the highest elongation of multiplied shoots (10 cm length/shoot) was noted on MS medium enriched with 1 mg l(-1) of gibberellic acid (GA(3)). The elongated shoots produced the highest number of roots (33.66 roots/shoot) on MS medium augmented with 30 mg l(-1) putrescine (PUT) along with 0.6 mg l(-1) 1-naphthaleneacetic acid (NAA). Rooted plants were hardened and acclimatized in the greenhouse with an existence rate of 98%. The standardized procedure with the use of PAs has enhanced the multiple shoot induction to threefold higher than the plants raised from PGRs treatments. The regenerated pea plants revealed the fivefold enhanced photosynthetic pigment, twofold enhanced antioxidant profile and the substantial growth in chloroplast count have been achieved in optimized SPD and BA supplemented MS medium compared to control plant. Start Codon Targeted polymorphism and Random Amplified Polymorphic DNA molecular markers recognized the genetic purity of the in vitro regenerated pea plants for their true type of nature.