Agronomical and Physiological Performances of the IRCA 41 Hevea Brasiliensis Clone in South-East of Cote d'Ivoire

Tapping panel dryness (TPD), characterized by latex out-flow stoppage after tapping, affect latex production in rubber tree, Hevea brasiliensis. To evaluate the sensitivity to this syndrome, 13 clones with good agronomic values were subjected to agronomic and physiological practices. This survey was conducted under production conditions using various Ethephon stimulation frequencies during five years. Analyses of variance and comparisons of averages were achieved from the lengths of sick panel (LSP) collected during the first five years of latex production. Results showed that the syndrome of TPD is under the influence of a genetic, physiological and hormonal determinism. The clone PB 217 confirmed its adherence to the class of low sensitivity to TPD. It was the same as the clone GT 1 for the class of moderate sensitivity and the clone PB 235 for the class of high sensitivity. The different variations of the stimulation frequency, of the duration of rubber production and the combination of the two factors, have influenced the sensitivity to TPD of the twelve clones except the clone IRCA 41 that remained steady in the class of very low sensitivity. This clone thus has good agronomic and physiological skills. The clone IRCA 41 deserves to be promoted and popularized by preference in the non-industrial sector to increase the rubber production in Cote d'Ivoire.