Propagation And Molecular Characterisation Of Rubber Tree (Hevea Brasiliensis Muell. Arg.) In Ghana

Abstract

The study was aimed at the propagation and molecular characterisation of some introduced clones of Hevea brasiliensis in Ghana. Propagation of H. brasiliensis by stem cuttings and in vitro techniques was used to study alternative procedures for mass production of rubber planting materials. Brown and green stem cuttings of Clone I and Clone II were soaked for 6 hours in 0.0-22.5g/L NAA followed by propagation in a nursery bag filled with nutrient-rich soil. Only the brown stem cuttings of H. brasiliensis survived. The % survival, length of shoots, number of roots as well as length of roots of Clone II was significantly (P<0.05) higher than Clone I. Stem cuttings treated with 15.0g/L NAA significantly (P<0.05) developed higher shoots (83.33%), number of roots (6.167), length of shoots (15.38cm) and length of roots (6.00cm) than the remaining treatments. There was significant (P<0.05) effects of NAA and Clone II in sprouting and rooting growth of the brown stem cuttings. The addition of 5.0mg/L kinetin in the MS culture medium significantly (P<0.05) enhanced higher shoot development (84.00%), number of shoots (3.60) and leaves (23.40) of the shoot-tip explants compared to other treatments. In nodal explants cultured on a medium without kinetin developed higher shoots (94.00%), height of shoot (4.80cm), number of leaves (19.20), number of shoots (6.00) and number of roots (7.00) than those with kinetin treatments. However, 7.5mg/L kinetin of the nodal culture also performed significantly after the controls. A dendrogram derived from the UPGMA distinguished the rubber clones from four areas of Ghana into two clusters. The five SSR markers showed high degree of relatedness among the rubber clones which suggested high genetic similarity (IRCA317-5, IRCA41-2, IRCA331-6, IRCA230-4, IRCA109-3, B8-23) and some degree of diversity/variation (K2-18, IRCA840-7, PB217-8, PB217-10, IRCA317-16) among the clones. Thus, clones of interest could be selected for future breeding and propagation programmes. Successful in vivo and in vitro propagation as well as molecular characterisation (genetic similarity and diversity) of rubber tree (Hevea brasiliensis) in Ghana were achieved.