Effect of Three Types of Biochar in Cocopeat Medium on Shoot Cutting Production of Chrysanthemum

Abstract

Biochar is a popular growing media amendment that increases fertilizer and water use efficiency, nutrient retention and crop productivity in floricultural crops. In Sri Lanka, cocopeat is used as the major growing medium for most of the floricultural crops. Therefore, the objective of this study was to incorporate biochar as a potential media amendment to improve the performances of plants through the enhancement of media properties. The performance of Chrysanthemum (Dendranthema grandiflora) was tested in amended media, as Chrysanthemum shoot cuttings is one of the most important floricultural products exported from Sri Lanka. The experiment was conducted with four treatments: B1 - 80% Coir dust+ 20% paddy husk biochar (v/v); B2 - 80% Coir dust+ 20% coconut shell biochar (v/v); B3 - 80% Coir dust+ 20% pine wood biochar (v/v) and C - 100% Coir dust (control). Incorporation of biochar significantly (p < 0.05) changes pH, electrical conductivity (EC) and water holding capacity (WHC) of the growing medium. Compared to the control, the time taken by Chrysanthemum shoots to reach standard size and quality did not show a significant (p > 0.05) difference in B1 while B2 and B3 showed significant (p < 0.05) differences. The number of shoots produced per plant three weeks after the first pinching and the post-harvest life and rooting performance was not significantly (p > 0.05) different among treatments. The incorporation of biochar into the coir dust growing medium for Chrysanthemum showed promising results which need to be assessed using other substrates and different mixing ratios.