Enhanced Micropropagation Protocol of Jojoba (Simmondsia chinensis L.)

Abstract

Jojoba (Simmondsia chinensis) is famous for its high-quality fixed oil production with various applications. Micropropagation is an efficient method for in vitro multiplication of plants. Thus, the present study aimed to explore an optimum medium for micropropagation of jojoba. Two experiments were conducted. In the 1^st experiment, nodal explants of in vitro seedlings cultured on MS medium supplemented with 1,2,4,6,8 or 10 µM of each n⁶-benzyleaminopurine (BAP) or Kinetin (Kin) alone or in combinations (1+1+1, 2+2+1, 4+4+1, 6+6+2, 8+8+2, 10+10+2 µM) of BAP + Kin + IBA (indol-3-butyric acid) or NAA (α-naphthalene acetic acid) making up to 24 treatments, after 35 days of initial culture. Shoots obtained on optimum medium (OM) of the 1^st experiment were selected for further cultivation of nodal (NS) and stub (SS, leftover shoot base 3 mm in size) explants in the 2^nd experiment. Rooting was achieved ½ MS+4+4, 6+6, 8+8, 12+12 µM of IBA+NAA. Highest (91.12%) shoot induction with 16.63 number of shoots and 5.22 cm shoot length was obtained in the 1^st experiment at 4+4+1 µM BA+Kin+IBA, considered as an OM. In the 2^nd experiment, the rate of shoot induction was 100% from both SN and SS explants at 4µM BAP+4µM Kin+1µM IBA, respectively with 24.45 mean shoots and 6.56 cm shoot length were obtained from nodal explants after 35 days. Year-round data demonstrated 100% shoot induction during April-June on the above-mentioned combination of PGRs. Rooting frequency reached 55.20 %, with an average of 1.86 roots per shoot and 2.45 cm root length in ½ MS + 12 µM IBA + 12 µM NAA after 65 days. The rooted shoots were successfully acclimatized and grew well in the field.