Although the current disease affecting rubber plantations was suspected to be the Pestalotiopsis leaf disease at the beginning it has now been positively identified as the circular leaf spot disease (CLSD) by the Rubber Research Institute of Sri Lanka said former senior planter and agricultural advisor and consultant Lalin I De Silva.
The delay in identifying the leaf disease at RRISL could be due to the acute shortage of relevant scientists. It is reported that there are about 25 percent vacancies exist in addition to not having a Director to RRISL although the RRISL is the first rubber research institute in the world, De Silva said.
The GDP contribution from the rubber industry was 0.2 in 2021, he said.
The dearth of experts and the delay in filling the gaps has led to poor or impossibility of undertaking succession planning which is a greater threat to the rubber industry that is growing rapidly. Rubber-based industries are heavily dependant on natural rubber latex produced locally, he said.
The rate of the spread of the CLSD is not well established. This is a major issue as no one could rule out a probability of reaching the levels of economic threshold without real time data on factorial effects.
The impact on different clones, rainfall, relative humidity, health of the tree, soil nutritional levels, production statistics at regional level and the details of other threatening diseases such as white root disease have to be maintained using technically competent employees of different departments supporting the rubber development of Sri Lanka, De Silva said adding that claims such as a 30 percent crop loss from the national production due to CLSD in the previous season cannot be justified without real time data.
The rubber prices are reaching all time high levels and more than 20,000 hectares that have been abandoned previously due to poor prices have been harvested since last season. It is difficult to ascertain if there is an actual crop loss due to CLSD and the extra crop that was harvested from the abandoned areas have covered the deficit that may have been due to CLSD.
The absence of a permanent sampling method of the leaf fallen on the ground due to CLSD on a daily basis is another shortcoming in the system as the reality and the scope of the problem is not identifiable by default, he said.