RELATIONSHIPS BETWEEN CARBON STOCK IN THE RUBBER TREE AND LATEX PRODUCTION
The relationship between tapping systems and the balance between latex production and carbohydrate availability would be very informative. This present work aims to study the effects of tapping systems on enzyme activities involved with Non-structural carbohydrates (NSCs) dynamic. The result indicated that enzyme activities from RRIM600 with upward tapping was higher from that of downward tapping. This could be partly due to the gradient sucrose along the truck as it is more concentrated in higher position than the lower one. Sucrose synthase was proportional to sucrose content in bark of upward tapping. Meanwhile, Sucrose Phosphate Synthase and Amylase were higher in wood than bark. These enzymes were also significantly higher in upward tapping than downward tapping. Using immunolocalization test, amylase was located in both vascular rays of bark and wood. It was noticed that enzyme activities strongly related to sucrose content while the link with starch content could not be clarified yet. To eventually explain the whole picture of NSC balance and latex production, information of latex production yield and enzyme involved in starch synthesis must be taken into account.
Keywords: Non-structural carbohydrates (NSCs), rubber trees (Hevea brasiliensis Muell. Arg.), tapping systems, immunolocalization