Induction or early flowering in clones of Hevea brasiliensis and Hevea brasiliensis x Hevea benthamiana hybrid clones

Abstract

Early flowering was obtained in fourteen month old nursery plants of IAN 873 and PFB 5 (Hevea brasiliensis) treated for this purpose. Treatment with Cumarine and Ethephon was efficient only on ringbarked trees. Root pruning or horizontal training of shoots were ineffective in flowering though a break in apical dominance has been noted for the horizontal position. The use of Dimethyl Sulfoxide enhanced the penetration of the phyto-regulators into the leaves. No treatment was effective in inducing flowering in in H. benthamiana (clones IAN 717 and Fx 3899). The possibility is considered that early flowering is primarily due to the blockage of downward transport of photosynthates, with a consequent increase in its availability to the apical meristem quiescent zones.