Seed production of clones PB 86, RRIC 100 and RRIC 121 in three rubber growing areas of Sri Lanka

Abstract

The rubber seed production in wet rubber growing areas in Sri Lanka has gone to very low levels in the recent past affecting the culling process that should be adopted in establishing rootstock nurseries.From the three rubber growing areas studied satisfacton seed production irrespective of the clone was observed only in Kegalle region.Regional differences may be due to direct or influences of the climate and weather during flowering and pod set. Clonal differences seems to be existing in regions where climate or the weather is favourable for spread of diseases.Further RRIC 100 being a resistant clone for oidum and phytopthora.produced a higher percemage of good quality seeds compared with the other two clones.PB 86 and RRIC 121 which have below average tolerance to these two diseases.However currently country as a whole produces enough seeds to fulfill country's annual seed requirement for the production of rootstocks provided the seeds are collected and transported without delay