Evaluation of the Physicochemical Properties of Innovative Substrates Based on Rice Husk Biochar and Compost Inoculated with Trichoderma for Soilless Horticulture

Abstract

This study aims to develop a culture growing media with physico-chemical qualities compliant. Growing medias based on Trichocompost and rice husk biochar were formulated in varying proportions. The following formulations were used: 100% Trichocompost (SA), 25% Trichocompost and 75% biochar rice husk (SB), 50% Trichocompost and 50% rice husk biochar (SC), 75% Trichocompost and 25% rice husk biochar (SD), and 100% rice husk biochar (BC).Physical parameters such as bulk density (BD), water holding capacity (WHC), total porosity (TP), air filled porosity (AFP), and chemical parameters including pH, electrical conductivity (EC), organic matter (OM), total nitrogen (N), P2O5, K2O have been analyzed. The results show that biochar-rich growing medias (SB, SC, BC) exhibit low BD (between 0,219 to 0,394 g/cm3), adequate TP (73,5% to 85,2%) and high AFP (20,73 to 29%), as well as good WHC (52,27 to 56,33%). Similarly, they have a higher K2O content (1,6 – 2,18%) and a higher pH (7,9 -8,67). On the other hand, growing medias rich in Trichocompost (SA, SD) are denser (BD between 0,610 and 0,626 g/cm3), less porous (PT and PA respectively between 57 and 62,4% and 8,93 and 10,87%). They also have richer N (1,38 – 1,78%) and, P2O5 (0,66 – 0,75%) a higher EC (3,31 – 3,97 (mS/cm). All growing medias meet the OM (> 40%) and NPK (<5%) content standards. SB and SC blends offer the best balance between physical and chemical properties. These results offer interesting prospects for the total or partial replacement of peat in soilless horticulture.