Somchai Chuan-udom, Arsaran Hilae and Ibrohem Yeedum

pp. 617 - 628

Abstract

Callus induction and plantlet regeneration from young leaves of high-yielding mature oil palm were
carried out using 10-year and 20-year-old trees from Thepa Research Station, Faculty of Natural Resources,
Prince of Songkla University, Hat Yai, and Trang Agricultural College, respectively. Culture media used in
this experiment were Murashige and Skoog (1962) and Oil Palm supplemented with various concentrations
of α-naphthaleneacetic acid (NAA) or 2,4-dichlorophenoxy acetic acid (2,4-D) or dicamba (Di) and antioxidants. Young leaves from 6^th to 11^st frond were excised, sterilized, cut into 5x5 mm pieces and cultured in
the dark at 26±4ºC or 28±0.5ºC for 3 months. The results revealed that MS medium with 200 mg/l ascorbic
acid (As) and 1 mg/l Di (MS-AsDi) gave the highest callus induction percentage (7.93) after culture for 3
months at 28±0.5ºC. Leaf segments from 6^th - 8^th frond yielded callus forming percentage at 10% (averaged
from 1, 2.5 and 5 mg/l Di containing MS medium). Ascorbic acid as an antioxidant at concentration of 200
mg/l supplemented in MS medium in the presence of 2.5 mg/l Di produced the highest callus induction
percentage (11.2) and number of nodules (7.06). A high percentage of embryogenic callus formation (66.67) was obtained when the calli were transferred to the same medium component supplemented with 0.5 mg/l
Di and 1,000 mg/l casein hydrolysate (CH) (MS-AsDiCH). Haustorial-staged embryos were observed to be
isolated as an individual embryo and germinated on MS medium without plant growth regulator (MS-free).
Development of root could be classified into two distinct types, fibrous and tap root.

Keywords

• oil palm
• embryogenic callus
• dicamba
• young leaf
• mature tree