Plant Physiological Assessment of High Metabolic Rubber Tree Clone in North Sumatra, Indonesia

Plant physiological assessment of rubber tree (Hevea brasiliensis) was aimed for yield optimization opportunity. In this present study, we observed the physiological status of PB 260 clone, a high metabolic, and the most popular clone in North Sumatra Province, Indonesia. The study covered three main rubber producer regions namely Asahan, Deli Serdang, and Labuhan Batu in 6 six different age of the plants. The physiological assessment was performed through latex diagnosis with four parameters i.e. total solid content (TSC), sucrose content, inorganic phosphorus (Pi) content, and thiols (RSH) content. The analysis results showed that there were no significant differences in TSC, Pi, and thiols contents in observed regions, while sucrose content in Deli Serdang was significantly lower than in Labuhan Batu, while in Asahan was not significantly different with other two other regions. The average sucrose value in Labuhan Batu, Asahan, and Deli Serdang were 5.82 mM, 5.74 mM, and 3.20 mM respectively. According to our analysis, PB 260 clone in Labuhan Batu had a good physiological condition, suggesting that the tapping intensity might be increased to optimize the yield. In Asahan, yield optimization should be performed prudently, whilst in the Deli Serdang region tapping intensity needed to be reduced due to poor physiological status. The harvesting system adjustment should be carried out carefully as we found a variety of physiological status among plant age.