Incidence of latex harvesting technologies on agronomic and physiological parameters and profitability of some rapid metabolic class clones of rubber tree (<i>Hevea brasiliensis</i>) in southwestern Côte d’Ivoire

Abstract

Rubber tree rapid-metabolism clones generally have interesting agronomic and physiological characteristics. However, they are mostly sensitive to tapping panel dryness and breakage due to wind. This could be probably due to overexploitation caused by high tapping frequencies and/or high hormonal stimulation systems. To try solving this problem, a study was carried out over nine years using clones PB 260, PB 280 and PB 330 planted at a density of 510 plants/ha in southwestern Cote d’Ivoire. The experimental design was a randomized complete blocks with different latex harvesting technologies. The estimated parameters were rubber yield, radial vegetative growth, physiological profile and the profitability of applied latex harvesting technologies. Results indicated that non-stimulated combined with high tapping frequency latex harvesting system (d2 0/y) showed a level of rubber yield comparable to that of tapping frequencies d3 and d4 in all studied clones irrespective of the level of hormonal stimulation applied. Furthermore, the absence of hormonal stimulation had no negative influence on the vegetative growth and the physiological profile of rubber trees. Every two days (d2) tapping system without stimulation generated a profit margin statistically identical to that of low tapping frequencies (d4, d5 and d6) irrespective of the level of hormonal stimulation. © 2017 International Formulae Group. All rights reserved. Keywords: Rapid-metabolism clones, Cote d’Ivoire, tapping frequency, Hevea brasiliensis , rubber yield, physiological profile