Macadamia is classified into a group of highly valued nut tree crop and it is also prized for carrying their richly flavored nuts, sweet and soft flesh. From graftings and cuttings, the two major means of propagating materials of macadamia having narrow genetic base, this tree is preferably propagated by grafting because it requires only 12 to 18 months for the first flowering and producing commercial quantities of seeds. On the other hand, cuttings are also practiced for a while just because of its rapid clonal multiplication but not commercial purposes because it produces inferior rooting systems. Cuttings can be sprouted of hundred of explant materials for micropropagation utilization. Micropropagation or in vitro regeneration is another prominent propagating tool of macadamia that can facilitate quicker multiplication of new rootstock and scion varieties with wider genetic base. The readily available auxiliary buds in nodal segments are commonly utilized as explants in a successful micropropagation of macadamia because it generates phenolic exudation on culture media which are very essential elements to make genetic variation of macadamia. Once this macadamia plant can be established from either of those propagating systems, the certain potentiality of this plant is able to continue its fruit bearing tendency over next 100 years. Hence, the three suitable propagating tools can be used in combination order to initiate several hundred plants from a desirable single mother plant. Beside this, the bright future research of many other relevant fruits and nut species such as almonds, chestnuts, hazelnuts, pecans, pistachios, walnuts etc. can be guided with this study to improve them in aspects of agronomic or commercial attributes.
Key words: Macadamia, propagation, micropropagation
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