Marilyn M. Belarmino and Darlyn B. Posas
A system for in vitro propagation of pummelo or Citrus maxima (Burm) Merr. Was established using shoot tip and single-node stem segment taken from young seedlings. The procedure involved the initiation of shoots from explant tissue, followed by shoot proliferation, >in vitro rooting, and finally, hardening of plantlets and potting out in soil. The agar-solidified Murashige and Skoog (MS) medium containing 30 g/L sucrose and supplemented with 0.2 mg/L BAP, 0.5 mg/L IBA and 40 mg/L adenine (MSP medium) was optimum. Eight-week-old shoots efficiently produced roots in agar-solidified MS medium containing 0.5 to 1.0 mg/L IBA compared with 4-wk-old shoots, indicating the importance of an adequate shoot growth prior to root induction. Using this system, 126 transplantable plantlets and 494 6-wk-old shoots can be produced from one nodal explant in a 4-month micropropagation cycle. One shoot tip explant can produce 26 transplantable plantlets and 50 6-wk-old shoots after 4 months.
Keywords: Citrus. Micropropagation Nodal explant Plantlet. Pumello. Shoot tip.
Annals of Tropical Research 19(1):(1997)