Rubber prices are on track for successive record highs as robust Asian economies led by China step up purchases, prompting producing countries to expand plantations to capitalise on the insatiable demand. Traders, policy makers and investors head to a rubber conference in Cambodia from Monday at a critical time when tight supply in major producing countries could see prices hitting new peaks up to April. Soaring prices have encouraged farmers in producing countries to try to tap as much as latex as possible and even plan plantation expansions, though the yield from new tress would only come in about five to six years. Tokyo rubber futures prices rose to a record high of 535.7 yen ($6.44) per kg on February 18 on supply concerns and hefty speculative buying by investment funds. Surging TOCOM prices have pushed physical rubber prices higher, with the benchmark Thai RSS3 being offered at a record of $6.40 per kg, while other Asian block rubber grades held at relatively high levels, dealers said. Farmers have also postponed replanting due to current high prices. They will keep the trees although they only get few drops of latex, said Suharto Honggokusumo, executive director of the Indonesia Rubber Association, referring to ageing rubber trees that would have normally been cut down and replanted after being tapped for almost 25 years. The two-day conference in Siem Reap, home to Cambodia