Effectiveness of a locally developed ethephon formulation on yield and related latex physiological factors of &lt;em&gt;Hevea brasiliensis&lt;/em&gt;

L T B K Fernando,P Seneviratne,N P S N Karunarathne,K M E P Fernando,V H L Rodrigo,H P P S Somasiri,T H P S Fernando,W G D Lakmini,K V V S Kudaligama,A P Attanayaka

doi:10.4038/jrrisl.v99i0.1894

Abstract

Ethephon is an essential agrochemical in low intensity harvesting of rubber (Hevea brasiliensis). Currently the total requirement for rubber industry is being imported in ready-mixed form adding a considerable cost to the plantations. Therefore, a new ethephon formulation was developed locally and the present study aimed to assess its effectiveness under Sri Lankan condition. The newly developed ethephon formulation was tested against a commercially available formulation with a small-scale field trial. No significant variation was observed in sucrose availability in laticifers with the new ethephon formulation. Significantly higher thiol and lower inorganic phosphorous contents of latex in trees may ensure long-term sustainability of the new ethephon formulation as a yield stimulant in rubber. Average dry rubber content of latex and latex volume obtained from a tree was comparable with both formulations. Accordingly, dry rubber yield resulted from trees applied with new ethephon formulation was comparable with the existing formulation and average values were 83.22 g and 86.67 g, respectively for new and existing formulations.

Highlights

Stimulation based low intensity harvesting (LIH) systems designed with various combinations of cut lengths, frequency of tapping and stimulation techniques are accepted by the growers as modern exploitation techniques to overcome constrains such as high cost of production (COP), lack of skilled harvesters and high bark consumption rates in rubber plantations
The massive outflow of latex induced by stimulation leads necessarily to an increase in the anabolic activities in the cells and specially biosynthesis of rubber and proteins involved in this renewal (Mesquita et al, 2006)
In trees applied with the new ethephon formulation, latex inorganic phosphorous content was significantly lower than that with the existing ethephon formulation (Fig. 1c)

Summary

Introduction

Stimulation based low intensity harvesting (LIH) systems designed with various combinations of cut lengths, frequency of tapping and stimulation techniques are accepted by the growers as modern exploitation techniques to overcome constrains such as high cost of production (COP), lack of skilled harvesters and high bark consumption rates in rubber plantations. New ethephon formulation for stimulation of rubber achieve comparable yields to that of conventional tapping i.e. S/2 d2 system (Gao et al, 2018). Average sucrose content of latex of trees applied with new and existing formulations were 3.47 mM and 3.97 mM, respectively and statistically comparable.

Results

Conclusion