Yield and latex physiological responses of PB 260 rubber clone stimulated with antioxidant and plant growth regulator-enriched ethephon

Abstract

Productivity of rubber can be increased through adoption of cultivation technology and implementing sustainable latex harvest system. Stimulant can optimize the latex harvesting process. However, planters have to adjust the concentration of stimulants to avoid over-exploitation and maintain the physiological condition. This study aims to determine the effect of ethephon stimulant enriched with antioxidant and plant growth regulator on production and latex physiological characteristics of PB 260 rubber clone. This research was carried out at the Indonesian Rubber Research Institute from June to July 2023. The study applied a non-factorial randomized group design with five treatments, namely 1) no stimulant as the control, 2) ethephon stimulant concentration of 1% + antioxidant + plant growth regulator, 3) ethephon stimulant concentration of 2% + antioxidant + plant growth regulator, 4) concentration of 2.5% ethephon stimulant, and 5) concentration of 3.3% ethephon stimulant. Each treatment was repeated three times and each replication consisted of three trees. The results indicated that the application of stimulant with various concentrations did not show significant differences in latex production, inorganic phosphate, thiol, and sucrose levels. The application of 2%, 2.5%, and 3.3% ethephon stimulants significantly affect the dry rubber content.