Effects of Ethephon Stimulation and Cut Length by Vertically Tapping on Rubber Yield and Latex Quality

Abstract

Harvest of natural rubber is facing the problems of a declining rubber price, less favorable agro-climate, and skilled tapper labor shortage. Reduction in cost of latex harvest by tapping machine in a straight line with ethephon stimulant will make rubber production more cost effective. To evaluate the effect of ethephon stimulation and cut length by tapping in a straight line on rubber yield and latex quality, a comparison of vertically tapping practices was conducted in clone Reyan88-13. The results showed that the increase of dry rubber yield was significantly obtained by the increase of cut length and ethephon stimulation concentration. Moreover, the increase of cut length and ethephon stimulation concentration significantly resulted in an increase of Cu2+ content, while the increase of ethephon stimulant concentration significantly led to a decrease in dry rubber content and Mg2+ content, but increase in thiols content. And also ethephon stimulation decreased consistently tear strength values, increased tensile strength and tensile permanent set values. The new tapping practice by vertically tapping with long cut length and high concentration of ethephon stimulant can be an alternative to relieve the stress of tapping complexity and tapper shortage.