EFFECT OF ETHEPHON CONCENTRATION ON RAW RUBBER PROPERTIES OF NATURAL RUBBER; A QUALITATIVE APPROACH

Abstrak

Skilled tapper scarcity has become one of the main constrains in the rubber plantation industry. This is a current and it will be a future challenge faced by natural rubber industry. To overcome this problem low intensity harvesting (LIH) systems with ethephon (2-Chloroethylphosphonic acid) stimulation is widely adopted to reduce the number of tappings per year without the reduction in annual yields. The properties of raw rubber made out of stimulated latex have not been considered when establishing the maximum dose of ethephone to be applied. The present study discusses the magnitude of variations of some selected raw rubber properties which are of commercial significance. Experiments were laid out in completely randomized block design with six treatments and three replications under  half spiral based once in three days tapping system (1/2S d3). Results obtained revealed that LIH systems with ethephon stimulation does not have any adverse effect on  raw rubber properties and are well below the limits fixed by ISO standard up to 3% ET concentration. However, properties were negatively affected with the application of higher ET concentrations beyond 3%.

Keywords:   ethephon concentration, Hevea brasiliensis, raw rubber properties, stimulation.