DOI: 10.36347/sjavs.2017.v04i08.003

Pages: 311-319

Abstract: Protected soilless culture is a method of crop production whereby resources such as land can be exploited at its best while its main constraint is the disposal of the growing media after use. This study is based on the reuse of disposed hydroponic substrate, namely cocopeat, after its useful lifespan. In order to assess the effect of used hydroponic substrate in open field crop production, an experimental trial was conducted at the University of Mauritius Farm, using tomato (Solanum lycopersicum cv. Swaraksha). The treatments were applied at different growth stages and calculated on a weight basis as follows: 0% cocopeat and 100% inorganic fertiliser (T1), 25% cocopeat and 75% inorganic fertiliser (T2), 50% cocopeat and 50% inorganic fertiliser (T3), 75% cocopeat and 25% inorganic fertiliser (T4), and 100% cocopeat and 0% inorganic fertiliser (T5) laid in a randomised block design with four blocks. T2 and T5 produced tallest plants and the greatest stem diameter (p < 0.05), while the highest value for percentage dry matter was obtained from T1 and T4 (p < 0.05). The most significant difference in nitrogen content in the tomato plants was noted in T3, followed by T1 and T2; while T1 and T5 resulted in significant difference for total plant phosphorus and total plant potassium (p < 0.05) as compared to control treatment. Tomato plants under T1 produced the highest fruit yield (27.5 t/ha) followed by T2 (26.4 t/ha). The findings demonstrated that a ratio of 1:3 of used hydroponic substrate to inorganic fertiliser could lead towards sustainable crop production. Hydroponic used substrate mixed with inorganic fertilisers can be used as soil amendments for crop production and a mean to mitigate the disposal problem of used hydroponic substrate.