The effect of the origin of the explant on in vitro growth of axillary buds of Hevea brasiliensis

Abstract

The effect of the origin of explants from different zones of the source plants on in vitro axillary bud growth in rubber (Hevea brasiliensis Muell Arg.) was investigated. Both juvenile (seedling) and mature (clonal) plants were used. Explants were harvested from shoots originated at different heights from 10 cm up to 180 cm. Mean lengths of the axillary shoots produced by the first nodal explants harvested from juvenile origin plants cut at 10,60 and 120 cm were 38.2,37.1 and 11.5 cm respectively at 10 weeks of culture. However, with clonal materials, mean lengths of 25 and 7.5 cm were obtained after 9 weeks of culture for the first nodal explants produced from plants cut at 30 and 180 cm heights. The results confirmed that juvenile materials are more responsive to in vitro culture. It was also revealed that the juvenile characters are more in the tissues close to the root system in mature rubber plants. Better understanding and manipulation of explants seems to be important for developing a successful protocol for micropropagation of clonal Hevea of mature origin.