Stimulants and Plugging Index in Hevea brasiliensis: A Preliminary Investigation of Plausible Effect of Some Stimulants on Plugging Index

he probable impact of some stimulants on plugging index during tapping in Hevea trees was investigated using the NIG 805 clone in the clonal garden of Rubber Research Institute of Nigeria, Iyanomo, Benin City. The experiment comprised of five (5) different treatments in three replicates. Each replicate comprised of 3 trees making a total of forty-five (45) trees. The study spanned a three month period (October to December) for two consecutive years. Stimulation was done once monthly and tapping done using the ½S, d/3 tapping mode. Data collected include length of tapping cut, initial volume (volume of latex flow within the first five minutes after tapping) and the final volume (volume of latex flow two hours after tapping. Results were analysed using ANOVA. The result for both years showed that there was no significant difference in the plugging index of the trees stimulated with Mortex 50, Vitex and control while there was a significant difference for those trees stimulated with Ethephone and Mortex 25.