Ex Vitro Root Induction of the “ Paisarn Taksin” Jackfruit Plantlets Derived from Culture

Abstract

The study on root induction of jackfruit ( The Paisarn Taksin ) plantlets derived from tissue culture, was conducted by cutting individual plantlets, about 2-3 cm long, in Murashige & Skoog solid medium containing 0.2 mg/l NAA and 15% v/v coconut water. These plantlets were transferred onto solid medium ( woody plant medium containing 10% ( v/v ) coconut water ), for a few weeks before transplanting into soil mixtures, compared to direct transplanting into soil mixture. The soil mixtures were consisted of sand : coconut husk : burned rice hull in various ratios for about 19 formula. The basal end of each plantlet was dipped into 5,000 mg/l IBA solution for 10 minutes. They were transplanted into those soil mixtures afterward, then incubated at 26 – 28^oC, 2,000 lux light intensity under 16 hours photo period for 45 days. After a few weeks the jack fruit plantlets which had been directly transplanted into soil mixtures were found dead. But the plantlets cultured in vitro before transplanting into soil mixture, looked so healthy and they were rooted very well. At 31 days after transplanting, the most effective root induction was found when these plantlets were transplanted into the mixture of sand : coconut husk : burned rice hull at the ratio 2:2:1, which gave about 80 percents rooting plants. The plantlets which were transplanted into burned rice hull alone were rooted about 70 percent. When these plants were transferred to the greenhouse, they were very healthy, well grown and were able to survive.